## PhD Projects for supervision at the University of Bristol

October 27, 2020

I welcome applications from students interested in doing a PhD in Combinatorics with me at the University of Bristol. A project description can be found here.

## Nine proposals for combatting the coronavirus pandemic in the UK

March 23, 2020

The following proposals have been suggested by a combination of world-renowned scientists (in several different fields), and ordinary people. As I believe they will be of great importance in combatting the pandemic, I’ve taken the liberty of collecting them together and sharing them publicly, in the hope that policymakers (and others) will act on them, or at least seriously consider them.

Proposal 1: Introduce a complete and compulsory Spain-style lockdown in the UK as soon as possible, and ramp up testing capacity as fast as possible.

An overwhelmingly strong case for this (both in the UK and the US) is made in the brilliantly researched article of Tomas Pueyo and his team, here. The weight of expert scientific opinion now supports Pueyo’s conclusion; an open letter, sent to the UK government on Thursday 19th March and signed (as of today) by 627 UK public health specialists, epidemiologists, scientists in relevant fields, and healthcare professionals, also calls for an immediate lockdown and extensive testing. The behaviour of many people in the UK over the last weekend (ignoring the government’s plea for social distancing), combined with the critical situation in Intensive Care Units (particularly in London, but it will soon happen in most other places), implies that government ‘guidelines’ are no longer enough: new rules with strict enforcement are needed, with enforcement by the police and maybe even the army if the police lack the manpower.

Proposal 2: While there is a limited supply of testing-kits available, try to test those whose positive diagnosis would do most to prevent new infections and deaths.

This won’t be easy and will involve some difficult trade-offs, but it could save a very large number of lives if it is done right. NHS staff and other key workers should presumably be prioritized to a large extent. NHS staff obviously cannot work from home and, if they are infected but do not realize, they have the potential to infect a very large number of other key workers (NHS staff) and also a large number of vulnerable people (patients with other conditions) who are more likely to die. Those in essential parts of the food industry, and delivery drivers, should also be given fairly high priority. Finally, while there is still a shortage of testing-kits, testing should not be spread too thinly in the rest of the population: if it can be concentrated to good effect in a particular district to stop an outbreak at a very early stage, or to suppress outbreak in an area where the NHS is being completely overwhelmed, then this should be seriously considered, even if it means less testing temporarily in some other districts. If they aren’t already, the NHS and the UK government should be taking advice on this specific problem from mathematicians specializing in probabilistic and computational modeling, as well as from epidemiologists and public health experts.

Proposal 3: Speed up the development of treatments, by loosening the rules.

In ordinary times, newly invented treatments have to go through more than 18 months of testing before becoming available, to make sure they don’t interact badly with any one of a vast number of other treatments that are available on the NHS. But these are not ordinary times – every day of delay in the availability of a treatment will almost certainly lead to thousands of deaths, many of which could have been averted by a treatment becoming available sooner. The government has to weigh these things up, even if adverse reactions to the treatments will result in some deaths – the question is, which course of action will result in the fewest deaths, and the least suffering?

Proposal 4: Speed up the development of a vaccine, by loosening the rules.

In ordinary times, vaccine-testing (like treatment-testing) is also subject to very strict rules, which slow it down. The government’s scientific advisors should perform a cost-benefit analysis of loosening these rules, even if there are some negative consequences of loosening the rules. Every day in the delay of the availability of a vaccine, could cost thousands of UK lives. There will be tough trade-offs, as discussed here, but we shouldn’t simply assume that the existing regulations are appropriate to this unprecedented situation; they almost certainly aren’t.

Proposal 5: Loosen the rules around privacy to allow more effective contact-tracing.

Today, South Korea reported the lowest daily number of new cases (64) in the last four weeks. For the last two weeks, the growth in the number of cases in South Korea has been linear (rather than the exponential growth Europe is seeing), and it has a very good chance of being successful in suppressing the outbreak. A key part of South Korea’s strategy was to relax the laws around individual privacy and surveillance, enabling detectives to trace the contacts of people who have tested positive, and to ensure that those contacts get tested; those who had been in close proximity with a known case received text-messages informing them of this. The ordinary rules on privacy and surveillance can be restored when the outbreak is over, but a temporary relaxation of the rules in the UK could well save a large number of lives (and help prevent catastrophic socioeconomic damage).

Proposal 6: Develop an instant contact-tracing app that people can download voluntarily, which notifies them if (in the last 14 days) they have been in close proximity with a newly-confirmed case.

Proposal 7: Recruit people who are immune to COVID-19, to work in care homes.

This would work well if immunity generally persists for a long time. It will take some more time for reliable data on this to be available, as the pandemic is only three months old, but when reliable data is available, a cost-benefit analysis of this proposal should definitely be performed.

Proposal 8: Introduce rationing (and government-controlled distribution) of several types of essential goods.

Supermarkets in the UK are currently completely unable to cope with demand, which has spiked tenfold since early March. If supply-chains become disrupted due to agricultural and delivery workers falling ill, this problem will become even worse. The government should step in to make sure everyone gets enough of the essentials. There will be enough to go around, provided the more fortunate don’t hoard everything. Professor Tim Lang, one of the UK’s leading food-supply experts, argues for these measures in this article, published today.

Proposal 9: Institute a Universal Basic Income for the duration of the outbreak.

Many jobs are under threat, particularly in the hospitality, catering, events, tourism and clothing sectors, but also in many other sectors impacted by social distancing; many have already been made redundant. The administrative load of means-testing financial relief for everyone in this situation would be completely unmanageable. A Universal Basic Income is the best solution (indeed, the only viable solution) for preventing mass-hardship – as argued powerfully by the Oxford economist Daniel Susskind in this FT article. (Skeptics should note that, before the pandemic, Susskind was not in favour of a Universal Basic Income.)

### Further discussion on the above proposals (and others), as the situation develops.

Update 1 (24th March): On the new UK lockdown.

Yesterday evening, the UK Prime Minister announced measures that almost amount to a Spain-style lockdown, effective immediately. It is permitted for citizens to leave home only for the following reasons:

1. Shopping for basic necessities, such as food and medicine – which should be as infrequent as possible.
2. One form of exercise a day, for example a run, walk, or cycle – alone or with members of your household.
3. Any medical need, or to provide care or to help a vulnerable person
4. Travelling to and from work, but only where work absolutely cannot be done from home.

Government instructions state that ‘These four reasons are exceptions – even when doing these activities, you should be minimising time spent outside of the home and ensuring you are 2 metres apart from anyone outside of your household.’ Gatherings in public of more than two people are prohibited (unless those two people belong to the same household), and all non-essential shops and businesses are required to close.

Analysis. It remains to be seen whether people will abuse the second exception (being allowed to leave home to take exercise), e.g., whether people will comply with the requirement to only exercise alone or with members of their own household, and whether they will stick to the ‘once-a-day’ rule and stay two metres from others while doing it. If they don’t, there could be a strong case for forbidding it; most people will not be seriously at risk from having to exercise indoors for three weeks. One should note that the second exception was not allowed in Spain.

The police do not yet have the required powers to enforce these measures (e.g. to fine those who violate the instructions), so legislation allowing enforcement will need to be passed with the utmost speed. Widespread testing is still urgently required, and as mentioned in the post, the police may require the support of the army, if enough people defy the instructions, or if the police suffer critical manpower shortages. The Metropolitan Police today reported that 19% of its police officers, civilian staff and community support officers did not report for duty because of contracting the coronavirus or because of having to self-isolate after being in contact with a known case.

Gil Kalai (an internationally-renowned mathematician with expertise in graph theory, among other areas) has today communicated to me a very good point about the UK lockdown. To delay the peak of the coronavirus outbreak in the UK (and reduce the maximum number of simultaneous infections), it will be important to minimise travel of people between different communities, so that, for example, the very serious outbreak in London (which already on Saturday was seeing Intensive Care Units in North London being overwhelmed) is not immediately transmitted to other districts and regions, many of which are currently less hard-hit; this will buy the government time for its emergency preparations. In mathematical (graph-theoretic) terms, minimising unnecessary contacts between different communities prevents the Transmission Graph from being an expander; this is important for suppressing the epidemic near the beginning, as pointed out for example in this study. Kalai observes that car-travel by individuals between different communities will be a particular danger (particularly if they visit ‘hubs’),  but car-travel is not specifically mentioned in the UK government instructions. Some car-travel will be necessary (for those in more isolated areas to buy food and medicines, for example, and for critical-sector workers to take their children to school if they don’t live within walking or cycling distance of the school). But it may be worth the UK government adding penalties for violations of the lockdown that involve unnecessary car-travel between communities.

A London-specific problem is that even today, workers from non-critical sectors were still defying the government’s instructions and using the London Underground, leading (for the second day this week) to crowded carriages where it was impossible to keep 50 centimetres (let alone 2 metres) from the nearest other occupant. This poses a great risk to critical-sector workers, in particular to NHS staff who have to use the Tube to get to work, and to the many patients and colleagues they will subsequently come into contact with. (As has been pointed out many times, due to the close proximity of commuters for 15 minutes or longer at a time, the Tube is an ideal environment for the spreading of the virus.) Substantial penalties should perhaps be introduced for people using the Tube in defiance of government instructions; Transport for London could also consider blocking the contactless/Oyster accounts of those who do not provide evidence (within a few days) of being a critical sector worker – though the administrative burden of this might be substantial.

If the UK lockdown is successful in initially suppressing the outbreak (possibly after it has been made more stringent), the next stage will be to prevent a ‘second peak’ by rapid containment action to suppress any new outbreak (this is the phase that Pueyo refers to as ‘The Dance’). In this phase, I expect Proposal 6 to be of crucial importance. But the sooner an instant contact-tracing app is rolled out, the better.

Update 2 (25th March, re Proposal 1): On NHS staff getting to work safely.

Several of my colleagues have suggested promising strategies to avoid a situation where significant numbers of NHS staff contract COVID-19 while using the Tube. One is to encourage cycling where possible (perhaps by distributing free bicycles, bicycle locks, bicycle lights and helmets to NHS staff who live a certain distance from their place of work). Another is to offer free or subsidised emergency accommodation within walking-distance of hospitals (though another solution would be needed for those with families). Finally, as of today, parking charges have been lifted for all Scottish hospitals, and in my opinion this should be done (for staff) in England too – as per this petition, already signed  in the last two days by over 380,000 people. (Update, 26th March: free hospital parking for NHS staff in England has now been announced.) When COVID-19 testing kits become widely available to NHS staff, it could also make sense for the NHS to offer free minibus transport to its staff, but this could be counterproductive (with NHS staff passing the virus to one another, e.g. if they are seated close together on journeys longer than 15 minutes), while testing-kits for NHS staff are still in short supply.

#### Update 3 (26th March). The need for systematic testing to determine the true COVID-19 infection-rates in each region of the UK; misleading headlines generated by an Oxford study.

This week, a team of researchers at Oxford (Lourenço, Paton, Ghafari, Kraemer, Thompson, Simmonds, Klenerman and Gupta of the Department of Zoology / Nuffield Department of Medicine) released a preprint (not yet peer-reviewed) stating that, according to their models, the current coronavirus data is consistent with around 50% of the UK population having been infected (at some stage) by COVID-19 by 19th March. (Though, as they say and as explained here, the data is also consistent with much lower proportions than 50% having been infected, hence the need for systematic testing to determine the true prevalence.)

The preprint generated some unfortunate headlines reporting stronger claims than the Oxford team actually made. Many experts (including other expert epidemiologists) are concerned that these headlines could encourage complacency and a lack of compliance with measures to suppress the UK outbreak, and a group of them wrote this letter to the Financial Times today, pointing out that the hospitalisation-rate among infected cases assumed by the Oxford team to get the 50% figure (0.1% of infections requiring hospitalisation) seems to lack empirical justification, and seems too low compared to the data from Italy. As the letter points out, Lombardy has a total population of 10,060,574. Despite stringent control-measures (a lockdown of the worst-hit provinces starting 21st February, and a complete nationwide lockdown starting 9th March), the total number of people in Lombardy hospitalised with coronavirus is 10,905. Hence, the number of hospitalised cases of coronavirus per head of the population in Lombardy is 0.108%. So the 0.1% estimate for the hospitalisation rate would only be close to the truth in Lombardy, if almost 100% of the population had been infected at some stage. (The letter also points out that their Italian colleagues Prof. Walter Ricciardi and Prof. Anna Odone have data indicating much higher hospitalisation-rates per head of the population than 0.108%, in some Lombardy towns.)

There is also the issue that the SIR model used by the Oxford team assumes that infected people are ‘well mixed in’ with uninfected people, in the general population. This is not quite true, since infections in the UK appear to have been concentrated in various hotspots (such as London) where infected individuals have a lower probability of infecting those from other parts of the country (such as Lincolnshire), where the proportion of infected people was much lower. In mathematical terms, the SIR model works perfectly if the transmission graph is highly pseudorandom, but this is not quite true for the actual transmission graph: there will be geographical concentrations of personal connections, for example. As pointed out by Gubbins (of the Pirbright Institute) and Hunter (of UEA) here, this will lead the SIR model to overestimate the number of infected people. But it will only be a slight overestimate, since (particularly in the early stage of the UK outbreak, before 19th March, which the Oxford team use to calibrate their model), very many of the contacts of infected people will have been uninfected.

It is worth remarking that even under the assumption that the hospitalisation-rate per infection is 3% (and given the data from South Korea, the UK rate will almost certainly be no higher than this, even accounting for the UK’s more elderly population), the Oxford model would still predict that about 15% of the UK population had probably already been infected (at some stage) by 19th March, so the predictions are somewhat robust with respect to quite large changes in hospitalisation-rate. (Though the calculations will need to be checked in the peer-review process.) Note that, even if the 50% figure were correct, it does not mean that those 50% will have long-lasting immunity; it is impossible to know at this stage how long immunity will typically persist for, and it will be of crucial importance for tackling the outbreak to perform repeated tests on recovered individuals to find out how long immunity typically persists for. (Some patients have reportedly recovered and then become ill with COVID-19 a second time, but it is possible that the testing may have been faulty; at this stage there is simply not enough evidence to know whether it is possible to catch coronavirus twice, as pointed out yesterday in this New Scientist article.)

The main conclusion we should take from the Oxford study (as the Oxford paper/preprint says itself) is that systematic testing is urgently needed to determine the prevalence-rate of COVID-19 infections per head of the population, in each region of the UK. (Note that this prevalence will be higher in some regions, for example London, than others, so systematic testing is needed in each separate region.) This could be done either by randomised testing, or (if this proves impracticable), testing all the inhabitants of one small district or town, in each larger geographical area. (The Italian authorities, for example, tested all the inhabitants of the town of Vò, in Lombardy – including those without any symptoms.) As the Government Chief Scientific Advisor Sir Patrick Vallance said yesterday, we simply do not know at this stage what proportion of the UK is currently infected. And we will have no way of knowing (for some time) whether immunity persists for a short time or a long time.

(NB: this update previously contained a calculational error, now corrected thanks to a comment below. The main conclusion, that systematic testing is urgently needed to determine the prevalence rates in each region of the UK, still stands.)

Update 4 (26th March): On closing non-essential construction sites.

It has been pointed out many times that construction-sites are an environment where COVID-19 can spread easily (it is impossible to maintain a 2-metre distance from coworkers in many situations, for example). UK Government instructions do not yet mandate that construction-sites close. Several companies have decided to close their construction sites anyway (e.g. Barratt, Belway and Tayor Wimpey; Persimmon is stopping ‘all but essential work’). But several have announced they are not suspending work (e.g. Cairns Construction, Berkeley, Crest Nicolson and Balfour Beatty). (See this BBC article and this Guardian article.) There could be a strong case for the government mandating that all but essential work is stopped (essential work includes, for example, the building of emergency temporary hospital capacity, or making other sites safe for closure as soon as possible).

Update 5 (26th March): On encouraging safe shopping; an issue with Sainsbury’s opening hours.

Most UK supermarkets are still unable to offer online delivery slots to customers under 70 years old (and not in strict isolation because of a suspected coronavirus case), due to being overwhelmed by the huge demand, so it is still necessary for many people to shop occasionally for essentials. Supermarkets and shops should take measures to minimise the risk of transmission during shopping; this could include providing a supply of disposable latex gloves at the entrance, encouraging people to wear their own disposable or washable gloves where possible, and incentivising contactless payments (perhaps by a discount). These ideas were suggested by the mathematician Prof. Darij Grinberg, in a comment below on this blog.

There is also the issue that the special Sainsbury’s shopping slot for NHS workers and carers only (7:30am-8am Monday to Saturday), comes right before their special hour for the elderly and vulnerable (8am-9am Monday, Wednesday and Friday), three days per week. This does not seem to be a very good way of arranging things, as the half-life of the virus in air is approximately one hour (and longer on plastic surfaces), the elderly are of course especially vulnerable, and at present there are high rates of infection among NHS staff (due to the lack of testing-kits). It would probably be advisable for Sainsbury’s to separate their slots for the elderly, from their slot for NHS workers and carers, by a greater length of time. Reversing the order of the two slots on Mondays, Wednesdays and Fridays could make sense if most NHS workers can shop later than 8am on those three days (and this would presumably not be an issue for hospital workers working 7am-7pm shifts). Some stock can be kept back for the elderly-only slot if this is placed a few hours after the slot for NHS staff (if panic-buying and stock shortages persist).

Update 6 (26th March): On (not) banning outdoor cycling for exercise.

Some have pointed out that the Spanish lockdown includes a ban on cycling. This may not be a very good idea, as the typical distance between cyclists (unless they are cycling in a big group in defiance of government regulations) is greater than the typical distance between pedestrians; added to which, it is many people’s main form of exercise, and preventing the taking of exercise has important costs, in terms of both physical and mental health. This, like the previous point, was observed by Darij Grinberg in a comment below. The UK lockdown at present permits cycling for exercise (and it is permitted to go outside to take exercise once a day, for up to two hours); as far as I can judge, this is probably sensible and proportionate.

Update 7 (26th March): On encouraging people to exercise at different times of the day in areas with a high population density.

The current UK government instructions allow people to leave their homes to take exercise once a day, for at most two hours per day. In cities with a high population density, such as London, this could lead to concentrations of people exercising at certain times of the day (e.g. the early morning or early evening), which is undesirable. A solution to this would be to encourage those who can to exercise at a time of the day based on e.g. the letter their surname begins with (or some other criterion that is independent of where one lives). This would be voluntary, as some people can only exercise at given times, due e.g. to childcare commitments, being a key worker or being a shift worker. This was suggested in a comment below.

Update 8 (26th March): On reciprocal agreements between countries to alleviate ICU staff shortages and equipment shortages.

As the well-known historian (and author of Sapiens and Homo Deus), Yuval Noah Hariri, pointed out in his F.T. article on 20th March, there will be significant advantages to cooperative actions between countries, in many aspects of tackling the pandemic – advantages to all the countries concerned in the relevant cooperative action. For example, many countries with early outbreaks are projected to shortly suffer a critical lack of ICU-trained staff (especially given high levels of staff sickness) – or indeed are already suffering such a shortage (as reported in London today, by the BBC).  On the other hand, several countries either have very small outbreaks currently, or appear to have successfully contained their outbreak. If country A has a serious outbreak and is projected to soon suffer a critical shortage of ICU-trained staff, whereas country B has no serious outbreak currently, an agreement whereby ICU-trained staff from country B will work in country A for a specified length of time (in return for some form of current or assistance), would be of great advantage to both countries. (One obvious form of future assistance would be as follows: if country A is able to suppress its outbreak, and country B subsequently suffers a serious outbreak, there could be a transfer of ICU-trained staff who are well-trained in tackling COVID-19, from country A to country B.)

In many cases it will also be advantageous for large groups of countries to agree on the joint procurement of certain types of equipment in which there is an acute global shortage, as larger blocs typically have more buying power than smaller ones and can also hedge more effectively against acute shortages. To explain the latter point, suppose that a particular product is crucial for tackling the epidemic, and three countries each have their own independent supply, and each supply will fail with a probability of 1/10 (independently). The probability that a particular country’s supply will fail is 1/10, but if each country agrees to help supply the two other countries should their supply fail, the probability that the bloc as a whole will ever suffer a failure of supply is only (1/10)3=1/1000. The (small) disadvantage to the most well-resourced country is that if all the supplies simultaneously fail, then the most well-resourced country would presumably have to share some of its remaining stock with the other two countries – but this event of simultaneous failure has a probability of only 1/1000, so the disadvantage is small. This is a simplistic analysis, of course (the independence assumption will not always hold exactly, and the failure-probability of 1/10 is for illustrative purposes only), but it conveys the idea.

In his article, Hariri outlines several other mutually advantageous cooperative actions between countries, some of which I will discuss below.

Update 9 (27th March): On international flights.

If the UK is successful in suppressing the current outbreak (through the lockdown, and other measures), but other countries are not, it will make sense to impose (temporary) restrictions on international flights arriving in the UK. (On 17th March, for example, the European Union suspended all non-essential travel into the bloc by non-EU nationals; the Canadian government announced a similar measure on 16th March, and announced on 25th March that, effective from midnight, international arrivals would have to self-quarantine for 14 days on entering Canada.) One mistake made early on by Italy was imposing restrictions only on flights from China; this meant for example that some flew to Italy from China via third countries, making it much more difficult for them to be identified and potentially tested for COVID-19 (or its symptoms), on landing in Italy. Hence, if restrictions are imposed, they should probably be imposed on flights regardless of their country of origin. Moreover, as pointed out by Hariri in his article, it will of course be necessary to maintain some capacity for international flights to and from the UK, throughout the crisis, for emergency purposes: the transport of medical staff and other critical personnel, and of medical equipment and other critical supplies, for example. As pointed out by Hariri, an international agreement by which emergency passengers were tested for COVID-19 before departure would be of great utility (the disease can of course be readily transmitted during air travel, due to the close proximity of passengers for a long period of time), though I differ from Hariri in believing that testing on arrival would also be of additional utility, until it is proven that the UK has the capability of suppressing and limiting the damage from a new outbreak.

Assuming the current outbreak is suppressed, in the medium-term, until it is fairly certain that the UK has the capability to suppress (and limit the damage from) future outbreaks that might occur in the event of reintroduction, it will make sense to consider restrictions (e.g. testing or self-quarantine) on international arrivals, though the benefits of such restrictions (given that there are other means of reintroduction) must be balanced against their socioeconomic costs and their (geo)political costs. If a vaccine or effective treatment is developed, or if a large enough proportion of the population develop immunity, or suppression measures become extremely effective, such restrictions would no longer be needed.

Update 10 (28th March): On avoiding ‘hubs’ where large numbers of people come into contact, and the urgent need for supermarkets to increase their home delivery capacity (if necessary with government aid).

It is intuitively clear that a dangerous obstacle to suppressing the current UK outbreak is the presence of ‘hubs’ (such as supermarkets and schools) where large numbers of people (who don’t otherwise come into contact) visit on a given day. This is confirmed by mathematical modelling, e.g. here. In fact, the presence of just one ‘hub’ in a community leads to a much higher (and sooner) spike in the number of simultaneously infected people, and this effect is considerably more serious than the effect of e.g. car-travel between different communities that avoids ‘hubs’ (e.g. children being moved from one parent’s house to another). Avoiding a situation where large numbers of people are simultaneously infected is obviously of critical importance in preventing the healthcare system from being overwhelmed, and therefore in keeping the number of deaths down. This is no doubt part of the thinking behind the updated government instructions that people should exercise locally if possible – e.g. they should not be visiting beauty-spots that require a car-journey, and other places that are generally popular with large numbers of people who don’t otherwise come into contact with each other.

[It is important to note that restricting car-travel between communities – even where this car-travel avoids hubs – is also important to buy time for the government’s emergency preparations – it will help delay the peak in the number of infections in less-hard-hit communities that are a greater distance from London, for example.]

The closure of schools (to children of people who are not critical workers) will help to cut down the risk posed by ‘hubs’, though schools must necessarily remain open to children of critical workers, and they cannot of course be closed for too long without very significant down-sides. But the danger posed by ‘hubs’ does imply that it is important to do more to minimise people’s need to visit supermarkets. Even if people are able to keep a distance of 2 metres or more from others while shopping, there is still a risk of infection – the half-life of the virus in air is a little over one hour, and its half-life on plastic surfaces (for example) is longer. Cashiers are also at particular risk of contracting the disease or inadvertently (and through no fault of their own) passing it on (if they display no symptoms). It is therefore of high importance for supermarkets to rapidly increase their capacity for home deliveries, even for those who are not elderly. Short-term government aid to facilitate this would be worth serious consideration – for example, through the emergency provision of refrigerated delivery vehicles (a particular bottleneck) and delivery staff. It may be necessary and appropriate to increase salaries for delivery staff, to aid and accelerate recruitment and to compensate for the risk they are at.

As of today (28th March), Sainsbury’s, Tesco and Waitrose are still unable to take new registrations/orders for home delivery in most areas of the UK, except for those classed as particularly vulnerable (e.g. the elderly) or those in strict isolation due to a suspected COVID-19 case, but the younger and less-vulnerable can also spread the disease, and in fact are more likely to do so, as there are many more of them and they leave their homes more often. (The fact that around 70% of cases are asymptomatic or quasisymptomatic, is relevant here; younger and less-vulnerable people will not necessarily know they have the disease, but can still be infectious in the asymptomatic period.)

Another means for supermarkets to increase their home-delivery capacity would be to make a temporary agreement with wholesalers with unused/under-used refrigerated delivery vehicles (such as wholesalers who generally supply the now-defunct hospitality industry, and/or restaurants), for a short-term loan of vehicles (and/or delivery drivers). This would presumably be of mutual advantage. Some wholesalers are already using some of their underused capacity (which is ordinarily used e.g. to supply restaurants, now closed to dine-in customers) to offer home deliveries, but an alliance with supermarkets such as I describe would enable them to use more of their spare capacity (as well as ensuring that the extra home-delivery capacity they provide is not restricted mainly to the wealthy).

Update 11 (3rd April): On emergency free / low-cost accommodation for NHS workers, in universities, hotels and vacant short-term lets.

In the last two weeks, reports have emerged that some NHS workers who lodge with their landlords have been requested to leave their accommodation at short notice, by live-in landlords worried that NHS workers are at a higher risk of infection. (The temporary suspension of evictions for 90 days, a.k.a. ‘eviction ban’, which took effect on 1st April, does not apply to lodgers.) Such requests, while often distasteful, might sometimes be understandable when the landlord is in a particularly high-risk group, so making them illegal would be problematic. (Though penalties could be considered for landlords not in a high-risk group.)

To help NHS workers in such situations, some hotels, some universities, and thousands of landlords are now offering free or very low cost emergency accommodation to healthcare workers. (Many hotels are all but empty, the short-term letting market is now down by 90%, and UK universities are currently operating only via distance-learning, so that much of their student accommodation is currently vacant.) Other universities and hotels should perhaps be strongly encouraged to do this. A fortnight ago, Merilee Karr set up a new website, NHS Homes, to put healthcare workers in touch with landlords and hotels willing to offer free accommodation for healthcare workers; as of today, about 400 homes are listed, worth a combined total of £1.2 million per month in rent. The government could consider introducing financial incentives to increase the number of homes offered (by hotels and by landlords). In the short-term, particularly while there is still a shortage of covid-19 tests for NHS staff, the need for emergency accommodation for NHS workers will only increase – for example, when NHS staff with a suspected case of covid-19 need to self-isolate from their families in separate accommodation. Incidentally, these problems underline the urgent need for ramping up testing-capacity.

Update 12 (5th April): On the possible exit-strategies for exiting the UK lockdown.

The first objective of the ‘suppression’ strategy that the UK government has adopted is to get the number of new infections per day down to a level that will not overwhelm NHS capacity. This essentially involves getting the ‘infectivity’ (defined as the average number of people each infected person infects) down to a number that is below one. About two weeks after this has been achieved, the number of newly confirmed cases per day will start to fall. (The delay is because of the incubation period of covid-19, and a delay in testing and getting the results.) But until it has been achieved, the number of new infections per day will continue to rise.

The following graph shows the number of newly confirmed cases in the UK, each day, up until yesterday (4th April):

Not too much should be read into day-to-day variation in the number of new confirmed cases; it appears the number tends to drop slightly at weekends for example, possibly because of reduced testing-capacity at weekends. It is still too soon to know whether the UK lockdown has succeeded in achieving a fall in the number of new infections per day; if it has not yet succeeded in doing this, the government will need to introduce further measures (such as mass-testing and contact-tracing, or stricter enforcement) until it does fall, to prevent the NHS from being overwhelmed. It is even a bit too soon to know (with a high degree of certainty) whether the Italian lockdown (introduced earlier) has succeeded in this, though we should know with more certainty in about a week’s time.

Obviously, a full lockdown cannot last indefinitely; the socioeconomic costs of continuing it for a very long time would become too great (leading eventually to societal collapse). When the number of new cases per day has been reduced to level that is manageable by the NHS, the two most vital questions the UK government has to decide will be (1) when should the full lockdown be lifted?, and (2) what measures should it be replaced by to ensure that the number of new infections per day doesn’t simply start to rise again in such a way as would overwhelm NHS capacity (i.e., a so-called ‘second peak’)?

Four possible answers to the second question have been proposed, each of which I believe are worth serious consideration.

Approach (1): The suppression (or ‘Hammer and Dance‘) strategy proposed by Pueyo. Lift the lockdown when the number of new infections per day has fallen to a very low level, and then subsequently stamp down hard on any new outbreak in order to suppress it, using a combination of contact-tracing, rapid and extensive testing (possibly of the whole population), rapid and effective isolation of known cases, and other measures such as Pueyo describes in his influential article. These measures would need to last, in some form, until a vaccine or an effective treatment has been developed, or until the capacity of the NHS has been sufficiently built-up to deal with a ‘second peak’.

Approach (2): The ‘Adaptive Triggering‘ strategy: alternate between lockdown and ordinary life, lifting a lockdown when the number of new infections per day falls below a certain pre-decided number N, and introducing a new lockdown when the number of new infections per day rises above another pre-decided number, M. Proposed by Ferguson et al. in their influential paper that caused a major shift in UK government policy.

Approach (3): The two-day working week, i.e. two days of ordinary life followed by five days of lockdown, repeated weekly until there is no longer any need to do so. Proposed by the systems biologists Alon, Dudovich, Karin and Korem, in this article.

Approach (4): A fortnightly variation on (3), with four days of ordinary life followed by ten days of lockdown, repeated fortnightly until there is no longer any need to do so. Also proposed, as a safer alternative to (3), by Alon, Dudovich, Karin and Korem, in this article.

Here, it is important to clarify that the days of ‘ordinary life’ in (2), (3) and (4) above would not be completely ordinary (by pre-pandemic standards). To prevent an uncontrolled growth in the number of cases on those days, the days of ‘ordinary life’ would still need to involve extensive testing, the prompt and effective isolation of symptomatic cases, and strict hygiene practises (such as regular hand-washing and the regular disinfection of workplaces, public places and vehicles of public transport). Those most at risk could also continue to be shielded from non-essential contact with others to a large extent. However, most workers would go to work as usual, and schools, kindergartens and universities would open as usual.

On ‘lockdown’ days, however, the situation would be broadly the same as it is in the UK currently, under lockdown: schools, kindergartens and universities would be closed, and most (except for key workers) would work from home. Most people would leave their homes only to shop for essentials (such as food and medicine), or to take exercise (and then only once per day).

Many experts (as well as many ordinary people) favour trying approach (1), as (if it goes according to plan) it would avoid further lockdowns (with their high socioeconomic costs) and it would simultaneously avoid future large increases in the number of cases. However, it is too soon to know whether approach (1) will definitely work, for the following reasons.

Approach (1) has not yet been fully and successfully implemented in any country that suffered a major outbreak. So far, it has been partly implemented in South Korean (but only partly, as schools remain closed, for example). Among all the countries that have suffered large outbreaks, South Korea is the only country (except for China) that has seen a consistent and long-term daily decline in the number of active cases:

South Korea has never in fact imposed a lockdown; the social-distancing rules in force are milder than those in the UK, and many shops, cafes and other businesses remain open. Instead, it has opted for a combination of mass-testing and intensive contact-tracing. It has made extensive use of drive-through centres for testing, and also tests asymptomatic people, estimated to be around half of all carriers of the disease. As of today (5th April), more than 460,000 tests have been performed in South Korea, compared to about 196,000 in the UK, whose population is 1.2 times larger.

It is important to note, however, that South Korea has not yet returned to normal life, properly speaking. Kindergartens, schools and universities remain closed, for example, greatly restricting the ability of parents to go to work. It was announced on 31st March that the reopening of schools (which had been due to take place on 6th April, after two delays) would be delayed for a third time (with online lessons starting on 9th April, instead).

As I said above, approach (1) has not yet been successfully implemented at all in any other country that suffered a large outbreak. (Singapore and Taiwan did adopt it with some success, but neither ever suffered a large outbreak. Also, the Singaporean government decided on 3rd April to close schools and most businesses, after seeing a recent increase in the number of new cases.) China imposed highly draconian measures that would not be possible in Western European countries, unless perhaps the disease were many times worse.

Moreover, while mass-testing on South Korean levels can certainly be replicated in the UK within weeks, it is not clear whether the UK would be able to achieve democratic consent for relaxing privacy laws to the extent that will allow for effective contract-tracing. Jung Won Sonn outlines in this article that contact-tracing as practised in South Korea has involved a level of surveillance and exposure of individual information that would currently be illegal in all Western European countries – as well being very resource-intensive. (In South Korea, large teams of detectives examine CCTV footage to track the movements of confirmed cases and identify their contacts, who are then notified by text-message of their proximity to a known case, and are asked to visit a testing centre. Text-messages are also sent by district authorities to the general public, listing the locations – including shops and restaurants – visited by individuals who subsequently tested positive.) There are of course less invasive and less resource-intensive methods of doing contact-tracing (such as the development of a voluntary contact-tracing app, described in Proposal 6 above). But we do not yet know for sure how effective these less invasive methods will be in reducing transmission of covid-19 in Western Europe. (The effectiveness the app will depend on the level of uptake, and how effectively people make use of the information the app provides, for example, as well as how fast transmission is taking place, given the suppression or mitigation measures we have in place.)

Since we do not yet know whether approach (1) will work, it is worthwhile to consider approaches (2), (3) and (4). The computer modelling of approaches (3) and (4) by Alon et al (see their article) suggest that approach (4) could well be capable of gradually reducing the fortnightly total number of new cases, and that approach (3) would also be capable of  doing this, though approach (4) would achieve it faster since it takes advantage of the fact that people infected on workdays would be at their most infectious on lockdown days (under the fortnightly cycle). However, the assumption they make on the effective transmission rate of covid-19 under lockdown (RL), namely that RL is close to 0.3, is rather optimistic. This study reported a figure of approximately 0.3 for the (highly draconian) lockdown in Hubei province, but it is not yet clear whether such low rates have been replicated by the European lockdown. A recent (30th March) study by Ferguson et al found estimates for RL (for the current lockdowns in Europe) all being at least 0.98 (though with a high degree of uncertainty); the probability that the UK lockdown achieved RL < 1 is estimated at 0.4. Further days of data (consisting of the number of new cases per day, probably for a further week or more) will be needed to properly estimate the effective transmission rate under the UK lockdown. Assuming the UK lockdown achieves RL < 1 (at which point the number of new infections per day starts to decrease; this is certainly needed before a lockdown is lifted), it may be necessary to slightly adjust the model of Alon et al to account for a higher value of RL than in Hubei province. This might lead, for example, to a need to replace the fortnightly cycle of 4 ‘ordinary’ days and 10 ‘lockdown’ days by a fortnightly cycle of 3 ‘ordinary days’ and 11 ‘lockdown’ days, to achieve the desired reduction in the fortnightly infection rate.

Compared to approach (2), approaches (3) and (4) have the advantage that they provide a predictable schedule around which people can plan their lives; they also make it easier for people to keep track of which regulations are in force on which days, which would improve compliance. Approach (2), on the other hand, is better-suited to responding to the current infection-rates, e.g. if these rise too high too suddenly during a period without a lockdown. It would also be worth considering a combination of approaches (2) and (3) – starting with approach (3), and then switching to approach (2) if the fortnightly number of new infections rises too fast. Similarly, a combination of approaches (2) and (4) could be used. The last combination would perhaps be better, as approach (4) is safer than approach (3), and at present I think it would be my preferred option if approach (1) fails.

Update 12 (11th April): On the possible non-persistence of immunity.

A preliminary study released on MedRxiv on Monday 6th April by a team of researchers at Fudan University (Shanghai) examined blood-samples from 175 (recovered) coronavirus patients who had suffered ‘mild’ symptoms (which may include a fever or continuous cough but do not include dyspnea, high respiratory frequency and low blood oxygen saturation), and had subsequently been released from Shanghai Public Health Clinical Centre. The study found that 30% of the patients exhibited levels of antibodies that may be too low to provide future immunity. (Most of those with low antibody levels were young; the patients in the 60-85 age-group had on average more than three times the antibody levels of those in the 15-39 age-group.) The paper will need to be peer-reviewed, and other scientists will need to attempt to replicate the findings, before we can draw any firm conclusions. But if the findings are confirmed, they may (for example) reduce predictions as to the future levels of population immunity that would arise from certain levels of infections. The study also raises the possibility that a vaccine might not provide effective protection for part of the population: if the immune system of some individuals does not produce antibodies in response to the actual virus, it might not do so in response to the vaccine either. Of course, all this is rather speculative at this stage; even if the findings are confirmed, they wouldn’t rule out the possibility of an effective vaccine. More research, and more data, is certainly needed on the persistence (or otherwise) of immunity, particularly in view of the tentative proposal to provide UK citizens with ‘immune passports’.

Update 13 (17th April): First systematic serological study enables a crude estimate of the percentage of the UK population exposed to covid-19 by 24th March.

The first systematic serological study (to my knowledge) was completed last week in Germany; the preliminary report is here. A representative sample of about 1000 inhabitants (not necessarily known to have been exposed to covid-19) was drawn from the town of Gangelt (a particularly hard-hit town, due to a carnival in February). For a preliminary result, blood samples from 500 people were tested. 14% of them were found to contain covid-19 antibodies (using a test claimed to have >99% specificity, though its sensitivity is not mentioned). Individuals who are currently ill with covid-19 do not always have antibodies and so the proportion of these individuals was estimated using the usual PCR tests, at 2%. The final estimate for the number of exposed individuals was 15% of Gangelt’s population. This enabled the researchers to estimate the case-fatality rate in Gangelt, at 0.37%. The case-fatality rate should be independent of the fact that Gangelt was particularly hard-hit (given that the healthcare system there wasn’t overwhelmed, which it wasn’t).

Now, assuming the case-fatality rates (in each of the various age-groups) in Gangelt is similar to the case-fatality rates in the UK as a whole (in each of the various age-groups) – which I think is a fair assumption as none of the healthcare systems in any of these countries/towns have been overwhelmed at any stage – one can use the case-fatality rate in Gangelt (together with the number of fatalities and the population histograms) to estimate roughly the true number of people exposed to covid-19 in the UK, by the beginning of the UK lockdown.

I’ll do this fairly crudely. The official UK data on covid-19 deaths for the last two weeks does not include covid-19-linked deaths outside hospitals (e.g. in care homes). The UK’s Office for National Statistics reports that there were 6,235 covid-linked deaths in England and Wales up until 3rd April (of which 4313, i.e. 70%, were in hospitals), but thereafter only figures for deaths in hospitals have been published. Assuming that in the last two weeks also, across all of the UK, 70% of covid-19-linked deaths took place in hospitals, one gets an estimate of a total of 13,729/0.7 = 19,600 covid-19-linked deaths in the whole of the UK, up until yesterday (16th April). About 88% of covid-19 fatalities in the UK have been people over the age of 65. Now, very crudely, assuming Gangelt contains roughly the same proportion of over-65’s as Germany as a whole, and bearing in mind that the proportion of the German population over 65 is 1.3 times that in the UK, one might expect the case-fatality rate in the UK to be around 0.0037/1.3 = 0.0028 = 0.28%. Assuming this, and also given that the average time between infection and death is about 23 days, one can estimate crudely that on 24th March, the first day of the UK lockdown, around 7.3 million inhabitants of the UK, i.e. 11% of the UK population, had previously been infected with covid-19.

It’s also worthwhile to do the same calculation for London, a major coronavirus infection hotspot (with significantly more confirmed cases per head of the population than any other part of the UK). The number of covid-19-linked deaths in London hospitals up until 16th April was 3,522. ONS and NHS data up until 3rd April suggests that in London, 90% of covid-19-linked deaths in London occurred in London hospitals. Hence, we may estimate the total number of covid-19-linked deaths in London up until 16th April (inside and outside hospitals) at 3,522/0.9 = 3910 deaths. Bearing in mind that the proportion of Germany’s population over 65 is 1.8 times higher than in London, one may estimate the case-fatality rate in London at 0.0037/1.8 = 0.00205, or 0.205%. Assuming, as before, that the average time between infection and death is 23 days, one can estimate crudely that on 24th March, the first day of the UK lockdown, around 3910/0.00205 = 1.9 million Londoners (i.e., 20% of London’s population) had previously been infected with covid-19.

One should do the above a bit more carefully using the distribution of times from infection until death, and the full population histograms of the UK, London and Gangelt (which was chosen, however, partly because it had a similar population histogram to Germany as a whole), but this won’t change the result much. Until we know the sensitivity of the German test, one should treat the 11% figure as a crude lower bound. But I wouldn’t be surprised if it was pretty close to the truth. Much too low for herd immunity, lower than the Oxford (Lourenço et al) ‘estimates’ of 15%-50%, but higher than the Imperial (Ferguson et al) estimates of 3-4%. The fact that herd immunity is almost certainly still a very long way off, provides (additional) evidence in support of the UK government’s decision yesterday to extend the lockdown for at least a further three weeks.

The (preliminary) results of the Gangelt study are consistent with the (preliminary) results of this (much larger) Stanford study released on 17th April on medRxiv in preliminary form, a serological study of 3,330 individuals in Santa Clara County in California. There is quite a lot of uncertainty over the sensitivity and specificity of the Stanford test, leading to prevalence estimates for Santa Clara County that differ by a factor of about 1.7, depending on which sensitivity & specificity assumptions are used. (Note that this is not a statement about confidence intervals; under one sensitivity-specificity scenario one gets a point estimate of 2.49% for the prevalence of covid-19 in Santa Clara County, and other another sensitivity-specificity scenario one gets a point estimate of 4.19% for the prevalence of covid-19 in Santa Clara County.) So the Stanford estimate for the case-fatality-rate in Santa Clara County is either 0.12% (for one sensitivity-specificity scenario) or 0.2% (for another sensitivity-specificity scenario). Given that the proportion of over-65’s in Santa Clara County is about half that in the UK, this leads (crudely) to an estimate for the case-fatality rate in the UK of either 0.24% or 0.4%. The figure of 0.28% used above is certainly between 0.24% and 0.4%. (To refine these estimates it will be necessary to estimate more precisely the sensitivity of both the Gangelt and the Stanford tests.)

It should also be reiterated that we cannot know from these studies (or any studies publicised so far) what level/concentration of antibodies typically provides immunity, or more importantly how long immunity will typically last for. It is important to conduct longitudinal serological studies, examining the same group of patients over a long period of time, to estimate how long immunity typically lasts for.

Update 14 (17th April): New UK cases by day, and the government’s decision to extend the lockdown.

The following graph shows the number of new lab-confirmed cases of covid-19 in the UK, each day. It strongly supports the government’s decision (announced yesterday) to extend the lockdown for another three weeks. The number of new cases appears to be plateauing, but only just.

It is usual to take 7-day moving averages in order to account for the fact that less testing typically takes places at weekends. This yields the following curve, which gives a similar picture of the situation.

It is hoped that the number of new cases per day will now start going down. This has already happened in Norway, which introduced a lockdown similar to the UK, much earlier (on 12th March):

It is to be hoped that the UK lockdown will eventually achieve the same decrease as has been observed in Norway. For the benefit of the small number of people still skeptical of that the lockdown has made a difference, it is instructive to compare the decrease in the number of new cases per day in Norway with the steady growth in the number of new cases per day in Sweden (a very similar country that has still not introduced a lockdown):

Update 15 (23rd April): On ways of tackling the shortage of PPE equipment in UK hospitals and care homes.

There is currently much discussion in the media over the shortage of PPE in UK hospitals and care homes. Some hospitals last Friday (17th April) reportedly had only around 24 hours’ worth of supply of certain key items (e.g. full-length, fluid-repellent gowns), and guidance was changed that day to enable re-use of PPE and to enable the wearing of aprons rather than full-length gowns if the latter ran out, which is certainly not optimal. This has been in spite of the UK’s relatively large initial stockpile. There have been reports that the government did not join the EU-wide scheme for procurement of PPE, for political reasons, even though it had that option. (Though the UK government has denied these claims, and has stated instead that the UK had not joined the scheme due to a communications delay.) Be that as it may, assuming that the EU procurement scheme proves successful (as of yesterday, the first deliveries were expected shortly but had not taken place), I do not see why the UK government should be unable to apply to join it at a later stage, at an appropriate buy-in price. At any rate, I am not sure why the possibility appears not to be under consideration, on either side.

Update 16 (30th April): On the value of surgical masks for healthcare workers in all staff-patient interactions in hospitals.

On 25th March, as reported here, Brigham and Women’s Hospital in Boston introduced a rule that all clinical staff were to wear surgical face-masks for all their interactions with patients (not just with patients known to be infected) — unless, of course, an N95 respirator, or similar, was being used instead. After just a few days, the number of new covid-19 infections confirmed per day among healthcare workers in the hospital had gone down from 12-14 per day (before the rule was introduced) to an average of around 8 per day – a reduction of about 50%. When, on 6th April, the hospital introduced an additional rule that all patients were to wear surgical masks during examinations by clinical staff, the number of new covid-19 infections confirmed per day among healthcare workers dropped further, to an average of around 6 per day. During the same period, the number of new covid-19 infections confirmed per day in the surrounding area (of Boston, and also in the state of Massachusetts as a whole) continued to increase. Very early in its outbreak, Singapore instituted the same rule in its hospitals, that clinical staff were to wear surgical masks in all interactions with patients (unless, of course, they were wearing an N95 respirator, or similar). According to this article (of 21st March) in the New Yorker, up until the time of writing (21st March), not a single healthcare-related transmission of covid-19 was known to have taken place in Singapore, despite the hundreds of cases that its medical system had to deal with up until that date. To quote from the article,

‘This included one case of a critically ill pneumonia patient who exposed 41 healthcare workers in the course of four days before being diagnosed with covid-19. These were high-risk exposures, including exposures during intubation and hands-on intensive care. Eighty-five per cent of the healthcare workers involved used only surgical masks.’

It is possible that other measures taken in Brigham and Women’s Hospital were partly responsible for the fall in cases among clinical staff there, and it is also possible that Singapore’s incredible success (no known healthcare-related transmission up until 21st March) was due in part to other measures. But it is also quite possible that the surgical masks rule made a big difference. Public Health England updated its guidance on 10th April to recommend that protective equipment be worn by healthcare workers in all cases of direct contact with patients (not just those with patients with a confirmed or suspected case of covid-19). This was welcome, but in the light of how important this might be, the UK government should perhaps be careful to ensure that sufficient supplies of surgical masks are maintained, to ensure this measure can be implemented in all cases, going forward. The opportunity-cost of failure to do so, could be severe.

Update 17 (6th May): On the NHSX contact-tracing app currently undergoing trials on the Isle of Wight, and the desirability of switching to a decentralised system compatible with the joint Apple-Google API, or putting in place contingency plans to do so.

There is an unfortunate situation developing at the moment, regarding the NHSX contact-tracing app currently undergoing testing on the Isle of Wight.

There are essentially two models for covid-19 contact-tracing apps, the ‘decentralised model’ where the proximity computations are done locally, on the user’s phone, and the ‘centralised model’ where the proximity computations are done on a central server (generally controlled by the government or health service, or a private company). The centralised model carries much greater privacy risks. These privacy risks are all but impossible to completely mitigate against, even with a team of top engineers working solidly on doing so for two months (time we don’t have); this kind of data is very difficult to fully anonymise, particularly if other databases can be used for deanonymisation – and these privacy risks may well significantly reduce people’s willingness to download the app. There is concern among many privacy and security experts that a government (or a private company, or a bad actor) could use the data from a centralised system (perhaps in conjunction with other databases) to recover sensitive personal information, e.g. about people’s close contacts. This concern was expressed in an open letter from nearly 300 internationally known privacy and security experts, who advocate instead a decentralised model. (A similar open letter from a group of 173 UK experts is here.) Worldwide, a majority of academic cryptanalysts are firmly in favour of the decentralised model, according to a world-renowned expert in the area. Similarly, the UK’s Information Commissioner stated on 17th April that ‘The starting point for contact tracing should be decentralised systems that look to shift processing on to individuals’ devices where possible.’ And this week, the Information Commissioner’s Office stated to the UK Parliament’s Human Rights Joint Committee that ‘As a general rule, the decentralised approach allows most readily for best-practice compliance with the data minimisation principle.’

Another crucial issue is that Apple and Google are currently developing a joint API (application programming interface) that will enable contact-tracing apps to work very effectively on both iPhones and Android phones, even when the apps are in the background – but, crucially, only if they use the decentralised model. A contact-tracing app that does not have access to the joint Apple-Google API will only be able to work well when it is running in the foreground, or when it is temporarily ‘woken up’ for a short period. This in turn depletes battery power (especially on iPhones), which will almost certainly discourage people from using the app in the way it’s intended – though of course, ‘waking up’ the app for short periods depletes the battery power quite a bit less than keeping the app running in the foreground.

Many Western governments have concluded, for the above reasons, that it is better to sponsor an app using the decentralised model – using the centralised model could reduce uptake due to privacy worries, and uptake needs to be pretty high, at over 60% of the entire population according to an Oxford study (of Fraser et al), for the app to be really effective at reducing the spread of covid-19. Further, the inability of apps using the centralised model to interact with the Apple-Google API will almost certainly lead to poorer performance, which (as well as making the contact-tracing less effective), may further reduce uptake. Germany switched last week from a centralised to a decentralised model. Other countries using decentralised model include Austria, Canada, the Czech Republic, Finland, Iceland, the Republic of Ireland (importantly – see below), Israel, Italy and Switzerland.

However, the contact-tracing app currently being developed by NHSX for use in the UK (and currently being tested on the Isle of Wight) uses the centralised model. This has been justified on the basis that, besides contact-tracing, it allows the NHS and the government to collect useful additional epidemiological information, e.g. regarding potential infection hotspots. But, the decision to go with the centralised model means that the NHSX app cannot access the joint Apple-Google API and will therefore not work so well on iPhones or Android phones (the problem with iPhones being worse – see below). This decision (if it is not reversed) carries with it the grave risk that the app will have reduced uptake – both due to privacy concerns, and due to not working well enough on iPhones and Android phones. It could therefore fail in its primary purpose, which is contact-tracing. This is clearly and impartially outlined in this Verge article (see also this Register article, which has a less balanced tone). The Australian ‘COVIDSafe’ app, which also uses the centralised model, indeed appears to have particular problems working on iPhones, arising from the fact that it cannot access the joint Apple-Google API. A report today in The Guardian suggests that, in view of the severity of these problems, the Australian government is going to switch their app to a decentralised model that can utilise the joint Apple-Google API.

Speaking to The Verge, digital rights expert Prof. Michael Veale, who is part of an international consortium developing decentralized contact-tracing protocols, said yesterday that there really is no way to build an effective contract-tracing system without the help of Apple and Google. A world-renowned expert in the area (and former colleague of mine) said they expected the NHSX app (and similar apps using the centralised model) to be almost impossible to use on iPhones, as a result of not being able to interact with the joint Apple-Google API. (And we should note that iPhones constitute more than 50% of the UK’s smartphone market.) NHSX engineers claim to have found a partial workaround, but it probably relies on the presence of Android phones in the near vicinity of iPhone users, and is unlikely to work well throughout the UK (except perhaps in busy city-centres). Some UK experts have already been analysing preliminary results from the Isle of Wight trial, and Prof. Michael Veale expressed the following view to The Guardian today.

‘The workarounds NHSX on both iOS and Android are using to create a centralised database seem to be fragile, disruptive to users and risk apps not registering contacts when they should. iOS apps are forbidden from using Bluetooth for long after they are minimised. To keep iPhones registering contact events appears to require either the user to constantly remember to reopen and refresh the app or, stranger still, sufficient Android ‘herd immunity’ among app users, where a nearby user of a non-iPhone, if in range, nudges nearby iPhones to not fall asleep, and to keep listening out.’

There is also the issue that the Republic of Ireland has opted for a contact-tracing app using the decentralised model; if this were not interoperable with the NHSX app, contact-tracing on the island of Ireland would be much less effective, as pointed out in this report of the UK Parliament’s Joint Committee on Human Rights, on digital contact-tracing, published today.

In the light of these issues, I strongly believe NHSX should strongly consider switching to the decentralised model; at least, they should put in place a contingency plan to do so, in the event that their centralised-model app has limited uptake and/or does not work sufficiently well on iPhones and Android phones. It is not too late to switch; Germany switched from the centralised model to a decentralised one only last week. If performance and/or uptake problems arise during the Isle of Wight test, there would perhaps be an even stronger case for switching. High-profile contact-tracing protocols using the decentralised model include the MIT-led PACT, the University of Washington’s PACT (which has the same acronym but is not formally linked to MIT’s PACT), the TCN Coalition and the Swiss-led D3-PT; NHSX could perhaps adopt one of these protocols, or make contingency plans for doing so. In his evidence to the UK Parliament’s Joint Committee on Human Rights, NHSX CEO Matthew Gould accepted that the technical difficulties of switching the NHSX app to a decentralised system were manageable (see the Committee’s report here).

Update, 8th May: the Financial Times reported on 6th May that NHSX has awarded a £3.8 million contract to Zuhlke Engineering, including a requirement to ‘investigate the complexity, performance and feasibility of implementing native Apple and Google contact-tracing APIs within the existing proximity mobile application and platform’, and with a deadline of mid-May. On 8th May, the Financial Times reported further that Matthew Gould, CEO of NHSX, had given the go-ahead to a project to develop a second contact-tracing app using the Apple-Google API, in parallel to the original NHSX app. This is very welcome news, particularly in view of continued doubt over whether the original NHSX app will work sufficiently well on iPhones.

Update 18 (16th May): On the preliminary results from the UK’s COVID-19 Infection Survey pilot.

Two days ago, preliminary results from the UK’s COVID-19 Infection Survey were released. The main points are listed as follows:

• At any given time between 27 April and 10 May 2020, it is estimated that an average of 0.27% of the community population had COVID-19 (95% confidence interval: 0.17% to 0.41%).
• It is estimated that an average of 148,000 people in England had COVID-19 during this time (95% confidence interval: 94,000 to 222,000).
• For individuals working in patient-facing healthcare or resident-facing social care roles, 1.33% tested positive for COVID-19 (95% confidence interval: 0.39% to 3.28%); of those reporting not working in these roles, 0.22% tested positive for COVID-19 (95% confidence interval: 0.13% to 0.35%)
• There is no evidence of differences in the proportions testing positive between the age categories 2 to 19, 20 to 49, 50 to 69 and 70 years and over.

However, the report states ‘We do not know the exact false-positive or false-negative rate of the current swab test for the virus. However, based on the very low number of positives in the results so far, we know the false-positive rate is very low (as even if every single positive result was false, this rate could only be 0.30%). We do not have information on the false-negative rate.’ It will be important to estimate properly the false-negative rate (equivalently, the ‘sensitivity’ of the test); if the false-negative rate is rather high, then 148,000 could be a significant underestimate. It will also be important to estimate properly the rate of false positives (equivalently, the ‘specificity’) of the test. Serology results (concerning the proportion of England’s population that have antibodies, and have therefore been infected at some point), are still awaited, but Sir Patrick Vallance said on 11th May that, based on very early results, it appears that very roughly 4% of the UK’s population might have been infected/recovered by early April. This is less than half the figure one would expect from the analysis in Update 13 above (which was just over 10%), suggesting that the Infection Fatality Rate for the UK might be over twice that of Germany (before adjusting for differences in recording protocol, and after adjusting for the different age profiles of the populations). But as the results are still very uncertain and lack sensitivity/specificity estimates, we will need to wait for better estimates before drawing any firm conclusions.

Update 19 (16th May): On the value of postponing the EU/UK Brexit trade talks (and extending the transition period) until the covid-19 crisis has eased.

Update 20 (25th May): On ways to reduce risk in human ‘challenge trials’ for a covid-19 vaccine.

As covid-19 infection-rates in European countries go down, it will become progressively harder and harder to find out from field trials whether prototype vaccines are significantly effective. (The ONS Infection Survey currently estimates that 0.25% of the UK population were infected with covid-19, at any given time between 4th May and 17th May; the 95% confidence-interval for this estimate is 0.16% to 0.38%, so fairly narrow.) The CEO of Astra-Zeneca, Pascal Soirot, referred yesterday on The Andrew Marr Show to a ‘race against time’ to test prototype vaccines in the general community before infection rates become so low as to make this infeasible. The trouble is, if a vaccine is tested by a field trial (that is, simply by distributing it to a large number of members of the population who have not yet been exposed to covid-19, and then monitoring how many of them become ill with covid-19) – then even if the vaccine is tested on 1000 people, if the prevalence is only 0.25% and infections last 10 days on average, then in expectation, only about five of the 1000 subjects will get exposed to the virus over a 20-day period – not enough to test properly the effectiveness of the vaccine. Professor Lawrence Young, of Warwick University Medical School, expressed the following view to The Guardian yesterday:

“Levels of infection in the community are already low, and if this virus behaves like other respiratory diseases and coronaviruses, there may be even lower levels over the summer. There will not be enough people secreting the virus to be in contact with volunteers in vaccine projects. It is just not going to work.”

This has prompted many UK and US scientists and campaigners to advocate that human ‘challenge trials’ for covid-19 vaccines be seriously considered. (In a ‘challenge trial’, healthy volunteers agree to be given a prototype vaccine and then deliberately exposed to the pathogen in question – in this case, to coronavirus.) The campaign-group 1 Day Sooner, which campaigns for human challenge trials for a covid-19 vaccine, has so far signed up over 25,000 volunteers for covid-19 challenge trials. Human challenge trials have been used successfully in the 1970s in the development of the Vaxcholera vaccine for cholera, in the 1980s and 1990s to aid the development of the Tamiflu influenza vaccine, in the early 2000s to aid the development of the FLU-v influenza vaccine, and in 2013 to test the vaccine for typhoid fever now recommended by the World Health Organisation for everyone over six months old who lives in a region where typhoid fever is common.

The Guardian article quoted above gives some idea of the balance of different opinions on challenge trials for covid-19.

‘[Prof. Lawrence] Young argues that human challenge trials should be considered “very seriously” for the UK. These would involve giving volunteers either a placebo or a vaccine, as is normally done in trials. But instead of waiting to find out how the two groups fare without interference, scientists would deliberately infect them with the Covid-19 virus. This would very quickly show if a vaccine works or not.

“Only very healthy young people – around the age of 25 – who have given informed consent would be used,” added Young, who points out that such trials have already been used to test the efficacy of vaccines for flu and the common cold. However, these ailments pose relatively low risks to volunteers. Covid-19 can have serious side-effects, mainly for the elderly but also in a few rare cases of young, apparently healthy people. This point is acknowledged by Young. “Before we went ahead with challenge trials, we would need to have developed some very effective therapy – an anti-viral drug perhaps – that could be used in the few cases where something went seriously wrong. This latter point has been stressed by the W.H.O. in its guidelines for human challenge trials. It suggests the least risky group to infect would be those aged 18–30 years. Only 1% of this group end up hospitalised with Covid-19, while fatality rates are around 0.03%. “Challenge studies should then be conducted in specialised facilities, with especially close monitoring and ready access to early supportive treatment for participants,” add the guidelines.

The idea of carrying out human challenge trials for a Covid-19 vaccine was also backed by Professor Arpana Verma, of Manchester University. “Vaccines give us the ability to protect the most vulnerable people in society. That is one of their key strengths. So I think it would be entirely justifiable to go ahead with such trials.”

But the proposal was firmly opposed by immunologist Professor Eleanor Riley of Edinburgh University. “Challenge studies are done for many diseases but only when strict criteria are followed. Firstly, the virus should be really well studied and its clinical behaviour understood in detail. It should also be incapable of causing severe illness in healthy individuals, or there should be a highly effective drug to clear the infection. None of these criteria are met for Covid-19, and I would be very concerned to hear challenge studies were being planned.”

The crucial point is that we should be thinking now whether we want to go ahead with human challenge trials, said Young. “We shouldn’t wait until we have a vaccine candidate on our hands and not know what to do with it.”’

## Lecture notes

July 10, 2019

Posted here due to popular demand: here are lecture notes for some past undergraduate-level, masters-level and graduate-level Mathematics courses I have taught.

Algebraic Methods in Combinatorics (16-hour Graduate Course, DPMMS, University of Cambridge, Spring 2011).

lecture1

lectures2to5

lecture6

lecture7

lectures8to10

lecture11

lecture12

lecture13

lecture14

Extremal Combinatorics (a first course in Extremal Combinatorics; based on a 22-hour lecture course given at Queen Mary, University of London):

Extremal Combinatorics (QMUL)

Random Processes (a first course in Markov chains, aimed at undergraduates with interests mainly in Applied Mathematics; based on a 33-hour lecture course given at Queen Mary, University of London):

Random Processes

## The gilets jaunes, Derek Hatton, anti-Semitism and anti-Zionism

February 24, 2019

Theodor Herzl, 1860-1904

Last Saturday, the French Jewish philosopher Alain Finkielkraut was shouted at in the street by several gilet jaunes protestors; one of them called Finkielkraut a ‘dirty Zionist sh*t’ and told him to ‘Go back to Tel Aviv’. Unwittingly perhaps, the protestor provided what may be the clearest example of anti-Semitism masquerading as anti-Zionism. If the protestor was truly anti-Zionist, why did he appear to endorse the central tenet of Zionism – that Jews belong in that small slice of land between the Mediterranean and the Jordan River, rather than in France (and Western Europe in general)? This, minus the hate, was the very conclusion reached by Theodor Herzl, the principal founder of modern Zionism, as he watched the public degradation of Captain Alfred Dreyfus at the École Militaire in Paris, 124 years ago. Dreyfus, a Jewish officer in the French Army, had been falsely accused and wrongfully convicted of passing French military secrets to Germany, after a campaign of hate in the press and on the streets of Paris; this was the infamous Dreyfus Affair of 1894-99, which convinced many European Jews – not just Herzl – of the need for a Jewish homeland.

Clearly, then, this protestor was using ‘Zionist’ as code for ‘Jew’, and did not want Jews in France. Alas, most recent cases of ‘anti-Zionism’ in the UK are somewhat less clear-cut; they may be anti-Semitism masquerading as anti-Zionism, but there is a chance that they just reflect an unbalanced view of world politics, perhaps caused by excessive media attention on Israel or by continuous exposure to only one side of the Israeli/Palestinian argument. To take one other recent example: Derek Hatton, the controversial former deputy leader of Liverpool Council, was suspended from the Labour Party on Wednesday, just two days after being readmitted (following his expulsion 34 years ago). This was after one of his tweets resurfaced from 2012, saying “Jewish people with any sense of humanity need to start speaking out publicly against the ruthless murdering being carried out by Israel!”.

I certainly agree with Labour’s decision to re-suspend Hatton: British Jews should not be considered any more responsible for Israeli government actions than a random, non-Jewish British citizen – i.e., they are not in any way responsible. (I leave aside for now the question of whether Israel is guiltier than other states, such as the UK, France or Germany; I would say it is not, given the situation it faces, but this is up for debate.) However, were there to be a new law proscribing anti-Zionist speech, as has recently been proposed in France, it is hard to see how any UK court could convict Hatton of an anti-Semitic offence ‘beyond reasonable doubt’. Surely Hatton would argue that he genuinely believed the Israeli government to be guilty of murder. (And this belief is almost certainly defensible; almost every European state has surely been guilty of murder at some point in the last decade.) And surely he could argue that he genuinely believed that condemnation of Israel from British Jews would have a positive effect on Israel’s future policies. Again, a defensible belief – condemnation from anyone might make a difference, and given that Israeli law identifies Israel as a refuge for Jews from all over the world, one can argue that condemnation from Jews might make more of a difference to Israel’s government than condemnation from non-Jews.

Hatton caused hurt to British Jews and has caused lasting damage to the relationship between the Labour Party and British Jewry. His remarks suggest a complete want of judgement, and at best that he is badly misinformed. But the answer such extreme views and statements must surely be greater efforts to publicise the truth about anti-Semitism and about Israel. A new law proscribing anti-Zionist speech risks playing into the hands of anti-Semites and bolstering conspiracy theorists who still believe (see comments here) that Jews control politics or the legal system.

## Does Jordan B. Peterson inadvertently help to rationalise Nazism?

February 17, 2019

### Nazism Watch — a private blog posting and commenting on news about Nazism, neo-Nazism, Fascism and the far-right in the UK, the US and mainland Europe.

I recently happened upon this interview with Jordan B. Peterson. In it he appears to be arguing that the Nazi programme in post-WWI Germany (including their anti-Jewish programme) was in some sense a natural human response to the horrors of the First World War (with people like Hitler seeing their comrades blown to smithereens), and to the economic and political conditions in Germany straight after WWI (various failed socialist and communist revolutions at the provincial level, the hyperinflation of 1923). It’s a dangerous argument to make, and misleading, in my opinion. Soldiers from all the belligerent countries in WWI suffered terribly; the UK suffered 744,000 military deaths and 1.7 million military wounded; France suffered 1.2 million military deaths and 4.3 million military wounded; Italy suffered 460,000 military deaths and 950,000 wounded. It’s true that these countries were nominally victorious, and that a Fascist regime did indeed come to power in Italy. But in none of these other countries (even Fascist Italy), did large numbers of people embrace the poisonous myth the Jews were responsible for their misfortunes. (In fact, a disproportionately high number of German Jews were killed in combat fighting for Germany, in WWI.) The high levels of active support for, and acquiescence in, the Nazi Holocaust, are still hard to explain from a rational perspective, in my opinion. Appearing to rationalise them leads Peterson into dangerous territory – indeed, some of the comments below the video on the Youtube page could have come straight from Hitler or Goebbels themselves. Evidently some still believe that the Jews are behind all the world’s problems.

## Swastikas left at office of Labour MP, CPS decides against prosecution.

February 17, 2019

### Nazism Watch — a private blog posting and commenting on news about Nazism, neo-Nazism and Fascism and the far-right in the UK, the US and mainland Europe.

Paula Sherriff, the Labour MP for Dewsbury, has had cardboard swastikas left on the doorstep of her office. (Dewsbury is the constituency next to Batley and Spen, where Jo Cox MP was murdered in June 2016 by Thomas Mair, an individual with far-right views, links to far-right organisations, and a history of mental health problems.) The Crown Prosecution Service decided against prosecuting the suspect, despite his admitting to placing the swastikas outside Sheriff’s office. Sherriff is appealing against this decision. According to an article in the Times today,

‘Last night the CPS defended its decision not to prosecute a man despite his admission he had left swastikas on Ms Sherriff’s office doorstep. Gerry Wareham, the chief crown prosecutor for Yorkshire and Humberside, said: “We considered this case carefully but the evidential test was not met to prove a criminal offence so we could not prosecute. The suspect was issued with a harassment warning. We understand Ms Sheriff’s concerns and take any potential threat of this nature very seriously.”

West Yorkshire police said: “We can confirm a complaint has been received in relation to the police handling of an investigation into incidents in July and August 2018, when offensive material was left outside the constituency office of a local MP. This matter has been referred to the Independent Office for Police Conduct who are conducting an independent inquiry.

“The tragic murder of Jo Cox in 2016 further emphasised the risks our MPs can face and West Yorkshire police regularly reviews security arrangements. West Yorkshire has local processes to ensure there is an effective response to any threats. We continue to review matters and ensure the appropriate measures are in place, in line with national plans, to keep not just MPs, but communities as a whole safe.”’

With political polarisation in the UK perhaps at its highest level since the 1930s, the increase in hate-filled rhetoric from both political extremes, and after the first ever murder of a sitting MP by a British extremist, perhaps the laws on criminal harassment need updating?

## Opinion: a People’s Vote is not only legitimate; there is a clear moral and political imperative to hold one.

December 29, 2018

In this article, I want to set out my views on the arguments for and against a second referendum on Brexit. Many people have expressed strong opinions on this issue, but in what follows I want to have a go at examining the arguments on their moral and political merits – as dispassionately, I hope, as the situation allows – though, as one can guess from the title of this article, I do come down heavily on one side.

The most common and strongly believed argument against a second referendum seems to be something along the lines of Theresa May’s claim before Christmas that it would ‘break faith with the British people’. The argument goes more-or-less like this. In June 2016, British voters were given a supposedly once-in-a-lifetime opportunity to settle the question of Britain’s EU membership. They voted to Leave, by a margin of 52% to 48%. To simply ask the same question again until one gets the ‘right’ answer (i.e., a vote for Remain) is surely not democratically legitimate, and moreover it could seriously damage people’s faith in democracy in Britain.

Supporters of this argument sometimes say that in the past, pro-EU governments have held second referendums (on whether to ratify EU treaties) when the first did not go the way they wanted. They point to the examples of Denmark and Ireland. Denmark held two referenda on whether it should ratify the Maastrict Treaty, the first in June 1992 and the second in May 1993. The first resulted in a ‘no’ vote, the second in a ‘yes’ vote. Similarly, the Republic of Ireland held two referenda over whether it should ratify the Treaty of Lisbon, the first in June 2008, and the second in October 2009. The first resulted in a ‘no’ vote; the second in a ‘yes’ vote. (I will return to these examples later.)

As the reader may have guessed, I think the above argument against a second referendum is seriously mistaken, for several reasons. First of all, and perhaps most importantly, we did not know in June 2016 what Brexit deal would be on the table. In a sense, we could not know, until the withdrawal negotiations were completed last month. We could only really guess at the rough outlines. And many people guessed wrong. Some people guessed completely wrong. Including well-informed people. Including some in the UK government. (And including, incidentally, myself.) Surely, now we know what deal is actually on offer, there is a case for asking us whether in fact we approve of this deal?

Part of the problem with the current situation is that, while there is only one type of Remain, in reality there are several different types of Brexit. Hard, soft, ‘no deal’, Norway-style, ‘Norway plus’, Canada style, ‘Canada plus plus’… And it is not at all clear, from the result of the original referendum, whether any of these options were preferred (by a majority of voters) to Remain. Some people almost certainly picked their ‘favourite’ form of Brexit, and had this in mind when they voted for Brexit in the original referendum – or else they voted based on one or two issues, such as sovereignty or immigration, which they hoped Brexit would resolve to their satisfaction. It is impossible for any one form of Brexit to satisfy the aspirations of all Leave voters. It is also clear, from the result of the Article 50 negotiations, that some forms of Brexit which some Leavers had in mind were not actually achievable. A ‘hard Brexit’ has turned out to be essentially incompatible with preserving the Common Travel Area in Ireland and avoiding a customs barrier in the Irish Sea, for example, and this issue has forced Theresa May herself to go back on some of her original ‘red lines’.

It is true that David Cameron said in May 2016, when he was fairly confident of a Remain win, ‘I am absolutely clear a referendum is a referendum, it’s a once in a generation, once in a lifetime opportunity and the result determines the outcome.’ Many Leavers took this (and similar statements of Cameron, ruling out a second referendum) to mean that a Leave vote would put an end to the argument. But given that there are several very different types of Brexit, it was surely irresponsible of Cameron to say that the original referendum would ‘determine the outcome’; how could it? Perhaps a win for Remain, by a significant margin, would have determined the outcome, as there is only one type of Remain; certainly, if Remain had won two-thirds of the vote, even the most ardent of Leavers would have had to accept the result as final, at least for the foreseeable future. Cameron mistakenly assumed that a Remain vote was almost guaranteed. His contingency preparations for a Leave vote were woefully inadequate, indeed almost non-existent, in the matter of discovering public opinion on different forms of Brexit, as in many other matters.

Here is an analogy: suppose a group of vintage car enthusiasts own together a vintage car that is one of a kind. They discuss together the possibility of selling it and buying together a different vintage car, but they are not all agreed on which alternative would be better (and some of them wish to keep the car they currently own). They would perhaps be foolish to sell their current car until they have actually found a replacement that is preferred overall to their current one. (And it is quite possible that no such replacement exists.)

I believe the best option would be to hold a consultative referendum in which voters were asked to rank (in order of preference) the various available options. There should be a public consultation about which options to list on the ballot paper – both Houses of Parliament, the government, and the Electoral Commission should be involved. There is an argument for not listing too many options; many voters might find it hard to rank more than four, and some of the options are quite close to one another, e.g. ‘Norway’ and ‘Norway plus’. My personal opinion is that four options should be listed:

(1) Remaining in the EU.
(2) Leaving the EU but remaining in the Single Market, i.e. the ‘Norway option’.
(3) Theresa May’s deal.
(4) The government should ask the EU to renegotiate the deal, with a view to negotiating a harder Brexit (meaning, a harder Brexit than Theresa May’s deal, avoiding an Irish backstop arrangement from which the UK has no unilateral right of exit, and with complete freedom for the UK to diverge from EU tariffs and rules). If the EU does not agree to this kind of renegotiation, then government should opt for a ‘no-deal’ Brexit. In these circumstances, the government would be free to try to negotiate side-deals, e.g. on citizenship, to mitigate some of the risks of a no-deal outcome – i.e. a so-called ‘managed no-deal outcome’.

It should be pointed out that options (1)-(4) above are listed in order of closeness, with option (1) being the closest possible relationship with the EU (full EU membership), and option (4) being the least close.

Options (2) and (4) would need further explanatory notes added. Norway is a member of the EEA (i.e., the Single Market), but it is not a member of the Customs Union. If the UK were to choose option (2), leaving the EU but remaining in the EEA, then it could either choose to remain in the Customs Union (this is commonly called ‘Norway plus’), or it could opt for a looser customs arrangement (more like the one in Theresa May’s deal). The choice over whether to stay in the Single Market is in my opinion more important than the choice over whether to stay in the Customs Union. (Remaining in the Single Market means keeping the four freedoms, freedom of movement of goods, services, capital and people, for example.) So I don’t believe option (2) needs to be split into ‘Norway’ and ‘Norway plus’; if the UK remains in the Single Market, it could be safely left to the government (with Parliamentary approval) to decide whether or not to stay in the Customs Union. A public consultation might well reach a different conclusion, however.

Option (4) is the most complicated, but I do not really see a way around this; voters need to know what is meant on the ballot paper by a ‘hard Brexit’, and the nature of this option is that it includes several somewhat different possible outcomes: a negotiated hard Brexit, a ‘No Deal’ outcome, or a ‘managed no deal’. Voters should be informed that is not at all guaranteed (given the recent public statements of European leaders) that the EU would agree to renegotiate a harder Brexit. In fact, as has become clear during the negotiations, a ‘hard Brexit’ is incompatible with (a) the insistence of both the EU and the UK government on avoiding a hard border in Ireland, (b) the EU’s need to control goods entering the EU from a different customs territory, and (c) the UK government’s insistence (and that of all the Unionist parties in Ireland) on avoiding a customs barrier in the Irish Sea. So under these constraints, a ‘hard Brexit’ might well have to mean a ‘No Deal’ outcome, or a ‘managed no-deal outcome’.

Ideally, voters should be given a booklet with a manifesto for each option, each written by campaign group approved by the Electoral Commission. (As in the original referendum, the Electoral Commission should choose the official campaign groups, campaigning for option.)

Such a referendum should in my opinion be consultative, rather than automatically binding, because it is possible that there might be no clear and unambiguous ‘winner’ among the available options. For example, it might be found that hardly anyone liked the Norway option, but a majority of voters preferred Remain to a hard Brexit, and a majority also preferred a hard Brexit to Theresa May’s deal, and a majority also preferred Theresa May’s deal to Remain! In this case, there would not be an obvious popular mandate for any of the options. If, on the other hand, a majority of voters preferred Theresa May’s deal to Remain, and a majority preferred Theresa May’s deal to a hard Brexit, and a majority preferred Theresa May’s deal to the Norway option, then a strong case could be made that there was a popular mandate for Parliament to vote for Theresa May’s deal. (In this case, a political scientist would say that Theresa May’s deal was a ‘Condorcet winner’: it wins in a head-to-head vote against any other single option.) The same would be true if any other option were a Condorcet winner: a strong case could be made that there was a popular mandate for Parliament for vote for that option.

As I said above, it is possible that there might be no Condorcet winner. A recent YouGov poll asked respondents to rank three of the options, ‘Remain’, ‘Theresa May’s Deal’, and ‘No Deal’, in order of preference. (It was based on a survey of 20,910 adults in England, Wales and Scotland, and it was taken between 4th-7th December 2018. It did not include the Norway option.) It found that 50.1% of respondents preferred Remain to Theresa May’s Deal, 52.1% preferred Remain to No Deal, and 64.6% preferred Theresa May’s Deal to No Deal. If these percentages are reflected in the general population, then (assuming for the moment that Remain is also more popular than the Norway option), Remain would (narrowly) be the Condorcet winner: it would be preferred by a majority to any other single option. However, the margin of error of the survey is estimated at 2.2%, so it is possible given this data that Theresa May’s deal is in fact the Condorcet winner. It is also possible, given the data, that 50.1% of voters prefer No Deal to Remain, 50.1% of voters prefer Remain to Theresa May’s Deal, and 64.6% of voters prefer Theresa May’s Deal to No Deal. If this were the case, there would be no Condorcet winner (assuming that the Norway option is not more popular than any other single option, either). But even if this is the case, I believe we should not be afraid to know it, especially given the current gridlock in Parliament, where there is currently no majority for any of the possible options. There surely cannot be any greater impasse than the current one.

This brings me on to the second strong argument for a second referendum: the absolute gridlock in Parliament. No option currently commands a majority of MPs’ votes: not Theresa May’s deal, not a harder Brexit (or a No Deal Brexit), and not Remain. If the Parliamentary gridlock continues right up until 29th March 2019, the UK could well ‘sleepwalk’ into a No Deal outcome, which a majority of voters oppose and which would probably do lasting damage to the UK’s global standing, its diplomatic relations and its economy, and would seriously disrupt the lives of many EU and UK citizens. It would also risk long-term peace and stability in Northern Ireland. A consultative referendum on the various options (as outlined above) could well help to break the gridlock. Even though it might not break the gridlock, it is surely worth a try: the gridlock (and the associated risk of No Deal) is surely worse than any risk to our democracy in holding a consultative second referendum.

There is a third argument, albeit one that may convince fewer people: some people have changed their minds, and some (mainly younger) people didn’t vote in 2016, and regret not having voted. This argument may carry less weight with hardcore Leavers, but should it? Is there a moral case for tying people to a decision they made two years ago, and now regret? Let’s imagine, for the sake of argument, that every single Leave voter now bitterly regretted their original vote and would vote for Remain if a second referendum were held tomorrow – would there still be case for saying that the decision of the original referendum was irrevocable? I’d be surprised if many people thought that there was. Most people will surely agree that it depends on the numbers who have changed their mind. And we just don’t know the numbers, at any rate until a consultative referendum is held.

In ordinary life, we understand that people make mistakes, and should be free (if possible) to try to correct them. To use the divorce analogy, which is apt in many ways given the nature of EU membership, if a married person decides at some point that they want a divorce, but during the divorce proceedings that person realizes they made a terrible mistake, and if (a very big if), their partner is prepared to give them a second chance, should the divorce court allow the couple to cancel the proceedings?

In political life, we also (usually) understand that people need to be given a chance to change their minds. In the UK, we have a general election every five years – or sometimes more often, at times of instability and crisis. If the public votes in a government, and then very much dislikes what that government ends up doing, they are given the chance to vote that government out of office after five years, or sooner. When voters are not given such a chance, we usually call the government in question a dictatorship!

On the other hand, in response to this third argument, it can be said that most Brexit voters have almost certainly not changed their minds, and if we were to hold a second referendum purely on the basis that some people had changed their minds, it could well have questionable legitimacy and undermine faith in our democracy, particularly as the first referendum was not billed as the first of several. However, I do not advocate holding a second referendum purely on that basis. The truly compelling arguments, in my opinion, are the first two. Firstly, the fact that we now know what options are on the table (and there are more than two!) – and we can now vote on the actual options, rather than guessing. And secondly, the fact that Parliament is gridlocked.

### Postscript

#### Denmark and Ireland: were their second referendums legitimate?

Though it is not directly relevant to the argument at hand, I believe there was quite a strong case for Denmark holding a second referendum in 1993, and a stronger case for Ireland holding one in 2009. In what follows, I will try to explain why.

The Maastrict Treaty (officially called the Treaty of the European Union) was signed by representatives of the governments of the twelve member-states of the then European Communities, on 7th February 1992. On its entry into force (on 1st November 1993), it created the European Union, from what before had been the European Communities. It had five key components:

– It created a ‘European Citizenship’, extending the right of freedom of movement from workers to all citizens of EU member states.
– It created a new common foreign and security policy.
– It contained agreements for closer cross-border cooperation in policing and judicial affairs.
– It introduced free movement of capital between EU member states.
– It paved the way for the creation of the Single Currency, the Euro. It created the European Central Bank and set out its mandate, and it established four ‘convergence criteria’ which countries were required to meet before joining the euro, regarding inflation, levels of public debt, interest rates and exchange rates.

Before the Maastrict Treaty could enter into force, member states had to ratify it. In most member states, ratification required only Parliamentary approval, but in France, Denmark and Ireland, it required a referendum. Denmark held its first referendum on whether to ratify the Maastrict treaty, on 2nd June 1992. It was rejected by a wafer-thin margin, of 50.7% to 49.3%, with a voter turnout of 83.1%. Following the ‘No’ vote, a process of renegotiation began. This culminated in the Edinburgh Agreement of December 1992, in which Denmark was given three major opt-outs:

– It is not required to join the Euro.
– It would not participate in formulating or executing common EU foreign policy, where defense is concerned.
– It has an opt out in the area of Justice and Home Affairs which means that it does not have to abide by EU laws concerning bankruptcy, asylum, divorce between citizens from different EU member states, and legal standards that set minimum rules in civil cases.

These opt-outs addressed major themes in the ‘No’ campaign. A second referendum, on the amended treaty, was held on 18th May 1993. The result was a ‘Yes’ vote by a margin of 56.7% to 43.3%, with a voter turnout of 86.5%.

Was it legitimate for the Danish government to hold a second referendum on the amended treaty? The opt-outs granted to Denmark were significant, particularly in the area of the Single Currency, of which Denmark is still not a member (and need never be). With hindsight, in view of the Euro crisis of 2009 onwards, the obligation to join the Single Currency was perhaps the most significant part of the original (pre-Edinburgh agreement) Maastrict treaty. An exemption from joining the Euro changed the calculus for Denmark, considerably. Rather than ‘asking the same question twice’, the EU was effectively offering an alternative arrangement more to the Danes’ liking: a two-stage negotiation, ending in a compromise.

What about Ireland’s two referenda on the Treaty of Lisbon? The Treaty of Lisbon was signed by representatives of EU member states on 13th December 2007. Significant provisions included a change to the voting system (in certain policy areas) in the Council of Ministers, an increase in the legislative power of the European Parliament, the creation of the post of President of the European Council (now held by Donald Tusk), a provision for closer cooperation between member states on defense and disaster response, and giving legal status to the Charter of Fundamental Rights of the European Union.

On 12th June 2008, The Republic of Ireland held a referendum on whether it should ratify the Treaty of Lisbon. The result was a ‘No’ vote, by a margin of 53.4% to 46.6%, with a (relatively low) voter turnout of 53.1%.

Major themes in the ‘No’ campaign included concerns that the treaty would compromise Ireland’s longstanding policy of military neutrality, and that it would affect domestic Irish policies on abortion, tax rates and workers’ rights.

Following the ‘No’ vote, the Irish government asked the European Commission for a legal protocol protecting its right to military neutrality, and its sovereignty over abortion laws, tax rates and workers’ rights, in the event that the Treaty of Lisbon were ratified. This was intended to address the most important issues in the ‘No’ campaign. After obtaining such a protocol, the Taoiseach announced a second referendum, which was held on 2nd October 2009. The legal guarantees obtained took some of the most emotive issues off the table, weakening the arguments of the ‘No’ campaign, the second time around. In addition, between the first and second referenda, the global financial crisis struck Ireland in full force. On 15th September 2008, Lehman Brothers filed for Chapter 11 bankruptcy protection, starting off a week known on Wall Street as the ‘great panic’; the Dow Jones index saw its worst decline since 11th September 2001, and Financial institutions across the world were affected. On 25th September, the Irish Statistics Office announced that the Irish economy had entered a recession; by mid-2009 this would worsen to an economic depression. The Irish Stock Exchange (general index) fell to a 14-year low on 26th February 2009, and in the first quarter of 2009, Ireland’s GDP per capita was down 8.5% from the same quarter the previous year. This coincided with the bursting of a property bubble and a sharp downturn in the Irish property market, turning into a full-blown property price crash by early 2009.

Ireland’s rapid economic growth from the mid-1990s to the late 2000s had been widely attributed to foreign direct investment stemming from EU and Eurozone membership. The second referendum campaign was influenced by fears that, if Ireland stepped back from further EU integration, EU investment in Ireland would suffer, and the Irish economy would be unable to recover. The ‘Yes’ campaign used stark slogans such as ‘Ruin versus Recovery’ – perhaps a genuine ‘Project Fear’, as opposed to the UK’s Remain campaign, which did not really deserve that label. But fear can be potent, and it can also be rational. In this case, it may have been decisive. In the second referendum, Ireland voted ‘Yes’ to ratifying Lisbon, by a margin of 67.1% to 32.9%, with a voter turnout of 59%.

Was it legitimate for the Irish government to hold a second referendum on the Lisbon Treaty? One can argue that the case for this was a good deal stronger than with Denmark over Maastrict. In addition to the legal protocols Ireland obtained, addressing major issues in the ‘No’ campaign, the economic situation had changed drastically between the two referenda, with the largest global financial crisis since the Wall Street Crash of 1929. As with Denmark, and far more so, the calculus for voters had changed. It made moral and political sense, in my opinion, for them to be asked again.

## Recent decisions may have increased the chance of a ‘no deal’ outcome in the Article 50 negotiations. It’s time to restore trust and moderation.

May 10, 2017

Formal negotiations on the UK’s exit from the EU are fast approaching. While it is theoretically possible that the UK Parliament could vote to reverse Brexit (by revoking Article 50) at any time before 1st April 2019, this appears highly unlikely. Almost certainly, it would not happen without a second referendum, which both the Conservative and Labour parties have ruled out. (The Liberal Democrats, on the other hand, promise a second referendum on the terms of Brexit when they become clear; but every poll since the General Election was called on 18th April has the Liberal Democrats on between 7% and 13%, so their chance of winning a Parliamentary majority is very remote.)

There is one possible outcome to the Article 50 negotiations which both parties should be trying hard to avoid – namely, a ‘no-deal’ scenario, where one or more issues derail the talks, and the UK ‘crashes out’ of the EU without an agreement at the end of March 2019 – which would presumably happen amid mutual recriminations and acrimony.

A ‘no-deal’ outcome could leave 4.5 million EU and UK citizens at risk of losing basic rights – the right of residence, the right to work, and the right to access social security and healthcare. (Except of course in the event of ’emergency’ unilateral guarantees from both sides, which one hopes but cannot assume would be forthcoming, and which anyhow would lack a mechanism for dispute resolution.) It would probably lead to the UK refusing to pay a ‘divorce’ bill of any significant size. It would risk the creation of a ‘hard’ customs border between Northern Ireland and the Republic of Ireland, thereby endangering the gains of the peace process. It would almost certainly preclude a mutually beneficial trade agreement from being signed in the near future. It might even endanger security and foreign-policy cooperation between the UK and the EU27, at least in the short term.

Both sides can and should aim for a better outcome. An agreement that will safeguard the rights of the EU27 citizens in the UK and of the UK citizens in the EU27. An agreement that will lead to the UK’s payment of an exit bill that could be considered ‘fair’ by an impartial observer, and is at least palatable to many reasonable people on both sides of the Channel. An agreement that will allow the maintenance of a close trading relationship in the future. An agreement that will safeguard cooperation on domestic security and foreign-policy issues, between the UK and the rest of Europe, for the foreseeable future.

I believe, however, that some recent decisions may have (perhaps inadvertently) increased the chance of a ‘no-deal’ outcome to the Article 50 negotiations. I should add that I still believe the chance of reaching some kind of an agreement to be significantly more than 50%. Being a mathematician by profession, I might hesitate to introduce probabilities into the discussion, had this not already been done by Lord Kerr and others. (Last week, Lord Kerr, one of the authors of Article 50, estimated the chance of a ‘no-deal’ outcome at 45%.)

The first decision I refer to is the decision to leak to the Frankfurter Allgemeine Zeitung a blow-by-blow account of the private dinner on 26th April at 10 Downing Street, those present being Theresa May, Jean-Claude Juncker and some of their colleagues. Juncker’s (alleged) words ‘Brexit cannot be a success’ have been widely reported on, but the account also appears to cast scorn on May and Davis’ lack of preparedness, and even suggests a rift between them:

‘Over the course of the evening, Davis praised himself three times for an heroic deed: namely having successfully brought British Data Retention before the European Court of Justice. At the time, he was still a Conservative backbencher; Theresa May, as Home Secretary, was responsible for drafting the law. Maybe Davis thought the multiple references would be a good icebreaker.

But his boss seemed not exactly amused by what, for her, was not a praiseworthy episode. The visitors asked themselves whether Davis would still be in charge of the negotiations after the parliamentary election.’

Several different motives for the leak have been suggested. One possible motive seems to be claimed at the end of the article:

‘In his [Juncker’s] entourage, the probability that the negotiations will fail is now estimated at “over fifty per cent”. One hopes that the British will come to their senses and face the uncomfortable reality while there is still time. And that at least business will put more pressure on the Government, since a chaotic Brexit could drag the country into an existential crisis. To communicate these concerns so bluntly is part of the strategy. Sometimes the alarm clock has to ring very loud to wake up even the most sleepy.’

Another possible motive, which I find somewhat plausible, is suggested here, but I do not wish at this stage to get into a detailed discussion about possible motives. At best, the person responsible showed a reckless disregard of the danger of damaging trust ahead of the negotiations. Indeed, the leak immediately undermined the trust of many in the UK government in some of their counterparts at the European Commission, and led to a hardening of rhetoric and positions, both by Theresa May and by some senior EU figures. It is a basic rule of international negotiations that trust is a crucial ingredient, and it is clear that the further apart the two sides are at the beginning, the lower is the chance of an agreement. I believe it is fairly clear that an undermining of trust and hardening of rhetoric and positions, such as took place after the leak, will make it harder (at least at the outset) for the negotiators to converge on an agreement.

The second decision I refer to is the suspension of the informal talks on the UK’s exit. Two weeks ago, the UK government requested a delay in the mid-term review of the EU budget, citing ‘purdah’ rules in the run-up to the UK’s general election. Even within the EU27, views seem to differ on the reasonableness of this request: President Juncker said on Saturday 29th April ‘The UK is currently blocking the decision and … it would facilitate the beginning of negotiations if the UK were to be able to withdraw the reservation that it has entered in respect to the mid-term review.’ On the other hand, according to a Bloomberg News article (4th May), ‘Three European government officials in Brussels told Bloomberg News that the short pause in budget talks for the U.K. elections wasn’t a problem for the bloc.’ Be that as it may, in response to the UK’s request, Martin Selmayr announced the following on Twitter (29th April): ‘Now, we’ll have to apply FULL PURDAH RECIPROCITY. Talks with UK, formal or informal, will start only after 8 June.’

I believe that the decision to suspend informal talks was a bad one. According to most experts in the study of negotiation (such as Deepak Malhotra), the absence or reduction of informal talks makes a final agreement much harder to reach – partly because it reduces the time available for reaching an agreement – and in this case, the deadline (mid-2019) is already very tight.

Predictably, the leak elicited a strong reaction from 10 Downing Street. Theresa May claimed on 3rd May that ‘the events of the last few days have shown that whatever our wishes, and however reasonable the positions of the Europe’s other leaders, there are some in Brussels who do not want these talks to succeed, who do not want Britain to prosper.’ The Guardian even reported the following on 7th May: ‘Key Downing Street advisers are said to be convinced that opponents in the European Commission are actively plotting to engineer a car-crash Brexit.’

I have not myself seen enough evidence to justify the conclusion that there is (among some in the Commission) a deliberate intention to engineer a ‘no-deal’ outcome. Such an intent would surely be Machiavellian in the extreme, given the European Council’s core negotiating principle no. 2 (‘nothing is agreed until everything is agreed’), which effectively links the residency rights of 4.5 million EU citizens to the final outcome of the Article 50 negotiations. However, it is undeniable that some in the UK now suspect such an intent, at least on the part of some who may have influence on the negotiations. These suspicions may have been fuelled by a number of ardently pro-federalist commentators advocating an extremely punitive course of action towards the UK, even at the cost of economic harm to the EU27, on the grounds that anti-EU movements in other member-states must be deterred at all costs. (See e.g. this article.) One may hope that the resounding election victory of Emmanuel Macron (who chose for his victory march the EU’s official anthem, ‘Ode to Joy’), together with the March 2017 Parliamentary elections in the Netherlands (in which anti-EU parties gained a total of only 15% of the popular vote), might reassure such commentators that the EU can afford to deal fairly with the UK.

It is now time for both parties to endeavour to restore trust and moderation to the debate, so as to maximize the chance of an agreement at the end of the Article 50 negotiations. (Donald Tusk’s calls for calm last week, and President Juncker’s statement yesterday that the leak was ‘a serious mistake’, and that it was not his doing, were most welcome.) Looking ahead, another piece of Malhotra’s advice is relevant: both the UK and the EU27 should think about the constraints facing the other party, and endeavour not to box themselves in with ‘red lines’ (a.k.a. ‘non-negotiable demands’) that the other party cannot realistically accept.

## ‘Nothing is agreed until everything is agreed’ – a mantra jeopardizing the rights of 4.5 million European citizens

May 2, 2017

Perhaps the most urgent issues in the upcoming Brexit negotiations are the future residency rights of the approximately 3.3 million EU citizens in the UK, and of the 1.2 million UK citizens elsewhere in the EU. Both Theresa May, and many of the EU27 leaders, have advocated an early reciprocal agreement on this issue; the security of millions of ordinary citizens is at stake, and they have already suffered a year of uncertainty. The ideal solution would perhaps have been for the UK government to unilaterally guarantee the rights of EU27 citizens already in the UK, soon after the referendum, on the understanding that the EU27 would reciprocate – and then for the EU27 to reciprocate, securing a cast-iron agreement on this issue before negotiations on tougher issues got underway. Sadly, neither side has yet given such a guarantee, either due to lack of confidence that the other side would reciprocate, or (at worst) because they wish to use the issue of citizens rights’ as a bargaining chip later on to exact concessions on other issues.

The European Council’s negotiating guidelines, published on Saturday, appear to place the future of these 4.5 million citizens in greater jeopardy.

http://www.consilium.europa.eu/en/press/press-releases/2017/04/29-euco-brexit-guidelines/

Core Principle 2 of these negotiating guidelines states “In accordance with the principle that nothing is agreed until everything is agreed, individual items cannot be settled separately.” As stated, this means that any initial agreement on future residency rights for citizens would be rendered invalid if other, more contentious issues (such as the ‘divorce bill’) prevent a final agreement from being reached by mid-2019, leaving 4.5 million citizens at risk of losing their residency rights.

If it truly cares about ordinary citizens, the European Council should answer the pleas of EU citizens’ campaign groups such as ‘The 3 Million’ to amend Core Principle 2, and agree to strike an early, cast-iron agreement on citizens’ residency rights, ring-fenced from the rest of the negotiations. Legal experts have assured The 3 Million that such a ring-fencing is legally possible. Short of immediate unilateral guarantees from both sides (which, sadly, do not appear to be forthcoming), an early, ring-fenced agreement on this is the only moral course of action, for both the UK government and the EU27.

The ‘all or nothing’ approach is reckless in the extreme, given the uncertainty over whether a final agreement will be reached. It is also deeply wrong. While this may not have been the intention, it perpetuates the treatment of 4.5 million human beings as pawns in the negotiations.

## Reflections on ∈

June 5, 2016

The following was prompted by Tim Gowers’ thought-provoking blog post, “$\in$“, on the EU referendum. While I think Gowers makes some very nice theoretical points, there are several important issues that undermine the conclusion, in my opinion. (I speak as a former advocate of Remain who has somewhat reluctantly changed his mind.)

I think the biggest problems with the EU are democratic / consitutional ones, and depending on how much weight one places on issues of democracy versus other issues (e.g. economic ones), it is perfectly possible for a thoroughgoing utilitarian to favour Brexit, as Gowers’ last paragraph tacitly acknowledges.

1. The democratic problems

A major problem with the EU is its so-called ‘democratic deficit’. This has two sources: firstly, the EU Commission, which functions as the EU’s executive and proposes legislation on which the European Parliament votes, is unelected. (Instead, Commissioners are nominated by the governments of member states.) By contrast, in the UK, the legislation on which Parliament votes is proposed by the government, which is made up of elected MPs. For many years there has been widespread concern throughout the EU (not just in the UK) that the EU Commission is insufficiently accountable to the EU’s citizens; yet this state of affairs has continued ever since the EU Commission’s creation in the 1950s. How likely is it to be reformed any time soon?

The second problem is with the European Parliament: though it is elected, voters throughout the EU are very much disengaged with the process. In 2014, voter turnout for the European Parliament elections was only 43% across the whole of the EU, and only 36% in the UK, compared with 66% in the UK’s 2015 general election. A related problem is the lack of scrutiny of and engagement with the activities of the European Parliament: in a recent survey, only 11% of UK citizens were confident of being able to name at least one of their MEPs, compared to the 52% who could name their Westminster MP. Partly because of this lack of scrutiny and engagement, national governments are sometimes able to use the EU Parliament to bypass national democracy and push through unpopular, illiberal measures at the European level, as was revealed recently in the Independent:

While I agree with Gowers that it would be disastrous if Boris Johnson were granted unfettered power, Westminster politicians are (with all their faults) subject to a high degree of public and media scrutiny, and must win general elections, which typically have a rather high voter turnout. The same cannot be said for Jean Claude Juncker or even for many MEPs. (I would point to Michael Gove as a more principled Leave campaigner, one who moreover genuinely believes in the cause; Boris Johnson on the other hand was rumoured to have written two speeches, one in favour of ‘Remain’.)

But perhaps the most serious constitutional problem with the EU is the ‘tyranny of the majority’, and this would remain a problem even if the ‘democratic deficit’ problem was solved.

The general problem of the ‘tyranny of the majority’ is ancient and well-known: it is possible even in a smoothly-functioning democracy, for a majority to consistently oppress a minority. This is a particular risk when there is a lack of empathy and shared identity between voters in the same polity, and this is unfortunately the case in the EU, and is likely to remain so for the foreseeable future.

A particularly egregious example of ‘tyranny of the majority’ within the EU is the incredibly harsh austerity package imposed last year on Greece (in defiance of the result of the June 2015 referendum there, of course). According to many (perhaps most) academic economists, this degree of austerity is likely to cripple Greece’s economic recovery in the long-term. Paul Krugman even speculated that the deal imposed on the Greek government by the Troika (the IMF, the EU Commission and the European Central Bank) was designed to topple the Syriza government – see e.g.

http://www.huffingtonpost.com/2015/07/02/greece-austerity-economists_n_7714148.html

Austerity was imposed on Greece largely at the behest of the German government, in an effort to recoup as much of their taxpayers’ money as possible, in the short term. (Though it remains to be seen whether they will actually be able to recoup less in the long term as a result of the austerity!) The imposition of austerity was strongly supported by German voters. And bear in mind Germany has hitherto been one of the more altruistic EU member states.

How is the UK at risk from the ‘tyranny of the majority’ within the EU? Well, since the Treaty of Lisbon, decisions in the EU in over 30 important policy areas are now taken by QMV (qualified majority voting) within the European Council, and this allows groups of nations in a minority to be consistently outvoted. This is a particular problem for the UK in the long run, because the UK (a majority of both its voters and its politicians) has a fundamentally different vision for the future of the EU, than many mainland Europeans, who want a much greater degree of political integration. Some even envisage (eventually) a federation of states along the lines of the US. This raises the possibility that the UK government will be gradually pressured (by a majority of other member states) to accept more and more political integration, against the wishes of a majority of its citizens. And many UK citizens are wary of this, not just paranoid UKIP types, but e.g. Cambridge-educated lawyers of my acquaintance! If it seems implausible, bear in mind that the Treaty of Lisbon was drawn up partly in order to adopt measures in the proposed European Constitution, which had been rejected by referenda in France and Holland. (The French and Dutch constitutions did not mandate referenda on treaties, only on a constitution!) See for example

To give an example of one prominent ‘federalist’, Matteo Renzi, who is regarded as a pretty mainstream politician in Italy, repeated in 2014 the call for a ‘United States of Europe’ –

I cannot imagine many UK citizens being supportive of such a vision. Some of my German and Italian colleagues declare themselves quite willing to see the end of the nation-state in Europe. This ‘hard-core federalist’ agenda may or may not have noble motivations, but there is an undeniable danger in going too far with it: a world with many nation-states may well be safer on average (averaging over both time and ‘space’, i.e. people) than a world with very few. If a government ‘goes wrong’ in one county, one can move to another; this is less easy if there are too few independent nation-states.

I admit that the creation of a federal European state along the lines of the US is very unlikely to happen in the short-term or the medium-term, if only because of the current impasse between Germany and France on how to achieve further fiscal and political integration (with Germany demanding joint fiscal rules to guarantee restraint before the issuing of joint Eurozone debt, and France demanding the latter before the former, in the name of ‘solidarity’). But further political integration in the short term is very much on the agenda, as illustrated by the following quotes from leading EU politicians:

Jean Claude Juncker (President of the EU Commission): ‘The Five Presidents’ Report includes a full agenda of work for the years to come, and I want us to move swiftly on all fronts – economic, financial, fiscal and political Union.’ (September 2015)

Jose Manuel Barroso (President of the EU Commission, 2004-14): ‘A political union needs to be our political horizon.’ (September 2013)

Guy Verhofstadt MEP (leader of the ALDE Group): ‘We must dare to take an even more radical leap: a leap towards a fully-fledged European nationality.’ (October 2012)

Angela Merkel: ‘We need more Europe, we need not only a monetary union, but we also need a so-called fiscal union, in other words more joint budget policy, And we need most of all a political union – that means we need to gradually give competencies to Europe and give Europe control.’ (June 2012)

Hitherto, the UK has often acted as a break on political integration within the EU, to the frustration of many EU politicians (and voters). This was eloquently articulated by the French politician Dominique Riquet, who argued on this basis that the UK should leave:

In this respect, both the UK and the rest of the EU might be better off in the long run, after a Brexit; it would leave the other EU states free and unshackled to pursue their more federalist vision, and it would leave the UK free from the risk of being pressured into further political integration.

Needless to say, democratic issues are an extremely important utilitarian consideration: citizens who feel their views are being ignored or overridden, are typically not very happy about this!

2. The principle of subsidiarity – its limited applicability

The democratic / constitutional problems outlined above would be less serious, if the ‘principle of subsidiarity’ Gowers describes, was widely applicable. But the EU’s principle of free movement of people, goods, services and capital (between member states), means that the ‘principle of subsidiarity’ does not apply, or is not applied, in many of the most important areas of civil life, both technically and in practice. For example, employment law (there is a huge amount of important EU legislation on this), immigration and asylum, human rights, justice, crime prevention, privacy, consumer rights, and of course external trade and foreign and security policy. It should be noted that the UK has an opt-out/opt-in agreement in some of these areas (e.g. immigration, asylum, justice and crime prevention), under which it can withdraw from the decision-making process, but if it does participate, it has to abide by the outcome of a ‘qualified majority vote’. See

https://commonslibraryblog.com/2014/09/08/extending-qualified-majority-voting-in-the-european-union-does-this-mean-the-end-of-british-sovereignty/

for more details.

The ‘principle of subsidiarity’ did not protect Greece from crippling austerity (the issue was indeed a supranational one, though the main country affected was Greece, from a utilitarian perspective.) Also, some recent high-profile EU legislation highlights the very limited definition of ‘subsidiarity’ the EU works with. The cap on bankers’ bonuses, which mainly just affects the City of London, seems at first sight to be a particularly flagrant violation of subsidiarity: in simple terms, it interferes directly with the amount of money employers/shareholders are permitted to pay their employees as a reward for their performance. It was of course defended by the European Court of Justice, on the grounds that banks pose a particular risk to the financial stability of the EU, but on these kinds of legal grounds, almost anything could be said to fall outside the scope of ‘subsidiarity’, in today’s highly interconnected world. Though I don’t necessarily want to go into the rights and wrongs of the bonus cap, the Bank of England argued that the bonus cap actually drove up bankers’ basic salaries, and this may undermine the post-crisis efforts of financial institutions to tie renumeration to long-term performance.

3. The ‘prisoner’s dilemma’, the ‘iterated prisoner’s dilemma’, and international treaties

One is left with the question of how to achieve the desired degree of international cooperation, in the aftermath of a Brexit. The ‘prisoner’s dilemma’ situations Gowers describes, do indeed demonstrate the desirability of international agreements/treaties, but these can and have been made (and adhered to), without the participants belonging to EU-style organisations. Further, if they are to be of much use, they must often involve nations from outside the EU, such as the US and China, especially in the given cases of climate change, corporation tax and overfishing in the North Sea.

Of course, for these to work, there needs to be a ‘penalty for reneging’ on the treaty. Such a penalty, however, is not contingent on belonging to an EU-style organisation. It can involve agreed sanctions (financial and otherwise) from other participants in the treaty, but even this is unnecessary. Because in fact, there is an extremely potent ‘natural’ penalty for reneging: namely, the unwillingness of other nation states to trust you in the future if you renege! And indeed, experiments simulating the ‘iterated prisoner’s dilemma’ in human populations have consistently found that ‘cooperative’ strategies are adopted by a majority of participants, and that these consistently outperform ‘greedy’ ones. (Axelrod famously tested a range of strategies against one another in computer simulations, and found the same thing.) This has been used to explain the evolution of cooperative behavior in both animal and human populations, see e.g. Axelrod’s ‘The Evolution of Cooperation’. Mathematically, in the ‘infinitely repeated prisoner’s dilemma’ where future payoffs are not discounted too much, cooperative strategies are ‘stable’. Of course, the ‘iterated prisoner’s dilemma’ is much closer to the situation in international relations, than the one-round version.

International cooperation is surely not contingent on ‘pooling sovereignty’ to the extent of having shared governmental structures with the powers of the European Parliament or the European Commission, with all the attendant democratic and constitutional problems this has (and which I discussed above). It can be achieved via other supranational organizations structures such as the UN or the OAS. Do we think the nation-states of South America or North America should have a common parliament and executive with similar powers to the EU’s, in order to achieve the desired level of cooperation? Should the US and Canada have such shared structures, for example? I humbly submit that this would be deeply unpopular on both sides of the border!

4. Utilitarian problems with EU policies

It should be mentioned that some EU policies have caused a major reduction in (worldwide) ‘utility’. In the Balkan crisis, perhaps the most serious foreign policy test the EU has faced, it failed miserably to prevent war and genocide, and in fact was instrumental in arguing for a UN arms embargo which prevented Bosnians from properly defending themselves against Karadzic’s marauding Bosnian Serb forces. Ultimately, the US and NATO were required to bring about an end to the conflict. Having said that, the EU’s post-conflict intervention has been a (mixed) success. See for example

Another example is the Common Agricultural Policy, which accounts for about 40% of the EU’s annual budget. Major effects of the CAP have been to subsidize farming in areas of the EU where it would otherwise be unprofitable, to keep food prices in the EU artificially high, to subsidize exports to outside the EU, and to impose high tariffs on imports from outside the EU. This has led to a net loss for EU citizens (for an indication of this, the OECD estimated in 2004 that state support for farming in OECD countries costs the average family of four \$1000 per year), and the CAP has long been criticized for harming producers in the developing world (through tariffs and ‘export dumping’), and hence stalling development there.

EU incentives for farmers to protect the environment have been welcome. But surely it is also in the UK’s (‘selfish’) national interest to protect our environment? I fail to see George Eustice’s problem with the protection of birds and wildlife habitats! Our agriculture cannot be ‘genuinely’ competitive (without subsidies) anyway. Were we to exit the EU, a sensible UK government would continue to subsidize farmers but to a lesser extent, prioritizing environmental protection over production to a much greater extent that the EU currently does.

5. The economy, and freedom of movement

I began by saying I thought it was perfectly possible for a thoroughgoing utilitarian to come down on either side of the debate, depending mainly on how heavily they weight the democratic problems of staying, versus the costs of leaving. To my mind, two of the most important costs of a Brexit would be the economic cost (both to the UK and to the rest of the EU), and the restriction on freedom of movement (again, for both parties).

Almost certainly, in the event of a Brexit, there would be a short-term economic cost to the UK (and probably a smaller cost per capita to the rest of the EU), though I would hope and expect that a trade and immigration deal fairly advantageous to both sides, could be worked out before too long, and that a desire to ‘punish’ the UK for leaving, and to disincentivize other exits, would not trump the common interests of both sides. There would also be a cost to those who (like myself) support freedom of movement for EU and UK citizens throughout the EU and the UK; in the short term, this freedom would certainly be reduced, though I don’t completely despair of winning the democratic argument within the UK for a high degree of openness to skilled workers from the EU. On the other hand, after a Brexit, the UK government would find it far politically easier to lift our extremely harsh restrictions on skilled workers from outside the EU. While I am personally in favour of a very high degree of openness to immigration from the rest of the EU, it does raise problems for our democracy (and cause widespread disenchantment therewith) when 77% of UK citizens view immigration as ‘too high’ (according to Oxford’s Migration Observatory) and yet the UK government cannot legally do anything to limit immigration from the EU.

To conclude, I plan to vote for Brexit, mainly due to the EU’s democratic and constitutional problems, but with a heavy heart, mainly due to the likely impact on the economy and freedom of movement.