Brexit, Dr. Who and Digital Identity

You are probably all sick of reading, hearing and dreaming about Brexit by now and I certainly do not propose to comment on whether no deal is better than a bad deal or whether the blockchain can create a virtual hard border for Northern Ireland, but there is one potential implication of Brexit that I do want to flag up here for discussion. Brexit may restart the discussion about ID cards.

To give just one instance of this meme, The Independent looked at a report from the think-tank Policy Exchange and said that “the UK should consider introducing ID cards after Brexit… it argues that Brexit marks a natural point at which to reform the UK’s immigration system”.

(The think tank Global Future went even further, saying that “the introduction of electronic identity cards would address many voters’ concerns about immigration without the need for Brexit.)

The Policy Exchange report was written by David Goodhart and Richard Norrie, and what they actually called for in the report is the creation of (essentially) a population register, giving everyone a unique number to facilitate interaction with the state. They say explicitly that the system “should not require a physical ID card, let alone the obligation to carry one”. In that newspaper article on the report, David goes on to say that they want to reopen the debate about ID management to “reassure people that we know who is in the country, for how long, and what their entitlements are”. It’s my emphasis on that word “entitlements”, and I’ll come back to it in a moment.

I wrote an article about identity cards for David when he was the editor of Prospect magazine, way back in 2005, in which I said that some form of citizen register “is clearly a good idea”. I wrote another article for him back in 2007, in which I said that the (then Labour) government should radically rethink its ID scheme, moving away from the obsession with ID cards and “focus instead on allocating a unique national identity number, backed by biometrics, to each citizen—that is all that needs to be held in a national register”. Nobody listened to me (except David!) and I do not recall ever being consulted on the topic by the government.

Anyway, the point of my writing all those years ago (and I also covered the topic in my book Identity is the New Money in 2014) was to separate the register that is used to determine uniqueness from the scheme that is used to determine entitlements. I think my general point and about moving to entitlements and leaving personally-identifiable information (PII) out of transactions has been not only borne out but reinforced by GDPR and subsequent developments in the world of social media.

Brexit bootstrap

If Brexit means an opportunity to rethink at the national level, but this time involve some expert opinion, I’m all for it. As I have written before at tedious length, we do not need a national identity scheme, we need a national entitlement scheme. And now is the time to starting thinking about what it might look like. So here go. As David touches on with his comment, the real solution is to our 21st-century identity crisis not an Indian-style Aadhar identity number or a Chinese social score, but a general-purpose National Entitlement System (NES). Very few people reading either the Policy Exchange report or this blog will remember the long ago days before the last Labour government’s attempts to introduce a national identity card, but there was a time when there were consultations afoot around a much better idea, which was a national entitlement card. As my colleague Neil McEvoy and I pointed out in Consult Hyperion’s response to that consultation, the “card” is only one mechanism for storing and transporting entitlements and in the modern age there might be better ones, such as mobile phones for example, that can not only present credentials but, crucially, also validate them (a subject I will return to).

Suppose that the vision for national identity (based on the concepts of social graph, mobile authentication, pseudonyms and so on) focused on the entitlements rather than on either the transport mechanism or biographical details? Then, as a user of the scheme, I might have an entitlement to (for example) health care, Wetherspoons or access to the Wall Street Journal online. I might have these entitlements on my phone (so that’s the overwhelming majority of the population taken care of) or stored somewhere safe (eg, in my bank) or out on a blockchain somewhere. Remember, these entitlements would attest to my ability to do something: they would prove that I am entitled to do something (access the NHS, drink in the pub, read about Donald Trump), not who I am. They are about entitlement, not identity as a proxy for entitlement.

It can be done

A decade ago I set out a vision for a 21st-century identity card. I tried to make it a vision that the public and the government and journalists and think tanks and everyone else could understand. It was a vision with genuine innovation and potential that subsequent technological developments have served only to sharpen. I tried to build a narrative founded in mass media because that’s where MPs and their spads get their science and technology education from (they are all arts graduates, so their knowledge of STEM is limited). This led me to suggest that in this matter, as in so many other things, Dr. Who should be the guide.

Just as Motorola famously created the flip phone around the Star Trek communicator, I created a vision of an entitlement service around Dr. Who’s psychic paper. As any devotee of the BBC’s wonderful series knows, the psychic paper shows the “inspector” whatever it is that they need to see. If the border guard is looking for a British passport, the psychic paper looks like a British passport. If the customs officer on Alpha Centuri wants to see a Betelguesian quarantine certificate, the psychic paper looks like a Betelguesian quarantine certificate. It the bouncer is looking for a party invite (as shown in the picture below), the psychic paper looks like a party invite.


Christopher Ecclestone flashes psychic paper.

(I remain completely serious using Dr. Who to frame the narrative. It may seem a little odd to base a major piece of national infrastructure on a children’s TV series, but as it turned out I was not the only person to look in this direction because the BBC fan forum the no-longer-online “Torchwood Think Tank” had the suggestion back in January 2007, noting “dialogue joke about wish fulfillment of Doctor Who’s Psychic I.D. card he flashes in Season 3, and how that’s the future of ID cards…”.)

We all grew up with Dr. Who, and the show engenders warm nostalgia. Now, obviously, there’s an age-related component to this. My favourite monsters were the cybermen and I always wanted to work for Brigadier-General Lethbridge-Stewart, so that gives my age away, but my kids enjoyed the show just as much and I’m sure the current generation are enjoying our new lady doctor just as much. Dr. Who is the perfect mechanism for explaining technology the public and to MPs and Ministers. However, “a national entitlement scheme” sounds a bit 1950s and a “psychic paper scheme” sounds too much like science-fiction, so I’ve decided to re-label it: welcome to the Brexit Bona Fides scheme.

Brexit bona fides

This is how the Brexit Bona Fides scheme works. Unlike Dr. Who’s psychic paper, this post-Brexit version of psychic paper only shows the viewer what he or she wants to see if the holder has the relevant credential. If you are trying to get into a nightclub, you need to prove to the bouncer that you are over 18. The bouncer is looking for a credential that proves you are over 18. You show your psychic paper to the bouncer and all it reveals to the bouncer is whether you are over 18 or not. All the bouncer sees is that you are old enough to drink. Provided you are over 18, of course. If you are not, the psychic paper remains blank, as shown below


You cannot forge this credential because it is digitally-signed by the issuer. If a 16-year old copies an 18-year old’s certificate into their psychic paper, it won’t work, because the incoming messages will be encrypted using the 18-year old’s public key, but the 16-year old lacks the corresponding private key (which can’t be copied because it’s never given up by the psychic paper — sorry, iPhone secure element). Since transmitting the photograph and appropriate credentials directly into the brain of the nightclub bouncer isn’t possible, we will of course need to use some kind of clever communication device instead. Luckily, just such a device already exists: the mobile phone.

My mobile phone would be able to check the entitlements that it is allowed to when presented by your phone, so none of us would need special equipment. I show up with my phone and claim that I am entitled to vote: my phone presents a QR code that is read by the polling clerk’s phone which flashes up my picture if I am entitled to vote or a red cross if I am not. I walk up to Wetherspoons and the pub requests an IS_OVER_18 credential. My Apple Watch (or phone or whatever) presents a list of virtual identities that have such a credential digitally-signed by an authority acceptable to Wetherspoons (ie, one that they can sue if I’m under 18) and, assuming that I’ve chosen one that is valid, my picture pops up on the bouncer’s Apple Watch. If I don’t have such a credential, the bouncer sees a skulls and crossbones or something. The customer never sees any of the jiggery-pokery hiding their personally identifiable information (PII). In 99 out of 100 cases, displaying your photograph is the only authentication required: There’s no need for the supermarket to check your fingerprints, for the doctor to demand a PIN or for the pub to take a DNA sample.

Watch Narrative Graphic

This isn’t really magic, or even that complicated. It’s all done using standard contactless communications, standard cryptography, standard protocols, standard chips, cards, phones and photos. Incidentally, after writing many year ago about how we could implement a psychic ID card using the same contactless technology as is used in Oyster cards, I literally fell off my sofa after settling down to watch a long ago Dr. Who Easter special only to see the BBC steal my idea! Yes, Dr. Who got on a London bus using his psychic ID card (see video here), clearly demonstrating that it has an ISO 14443 interface that can fool machinery as well as the psychic interface that can fool people.

Meanwhile, back in the real world… note that when using Brexit Bona Fides, no-one can read your psychic paper — no-one can check your Bona Fides* — unless they are allowed to and when they are allowed to, and all they can see is what they are allowed to see. No more showing the guy in the pub your name, date and place of birth and goodness knows what else just to prove you are 18. Under the hood, it’s all done using keys and certificates, credentials and local authentication: The nightclub bouncer has had to obtain a digital certificate that allows him to interrogate your ID card. His phone sends the certificate to your ID card. The ID card checks it, sees that it is asking for a proof of age. It sends back your photograph, digitally-signed (that’s how his phone knows it’s a real ID card, because it can check this signature). If you’re not old enough to drink, it sends back a digitally-signed red cross (or whatever).

Bona Fides will show the GP your health service number but only if you have the right to NHS healthcare, otherwise it will be blank. Bona Fides will show the employer your national insurance number (but only if you have the right to work in the U.K.). Bona Fides will show the pub absolutely nothing except your photograph (but only if you are old enough to drink). So this is a user-friendly way to implement all of the privacy-enhancing technologies that we would like to see incorporated in a modern national identity card scheme: sector-specific identifiers, pseudonyms, mutual authentication.


Now, this may have sounded far-fetched back in 2005, but let me point you to the new Louisiana smart driving licence. As a couple my LinkedIn contacts pointed out, this implements some of the key psychic ID concepts.

  • The smart driving licence app means that a holder can authenticate another person’s Louisiana digital driver’s license.

  • In the bar case study, it allows the customer to select which information she would like to reveal to the bartender—such as that she is over 21. That information is displayed on the phone with a photo and embedded QR code. The bartender scans the code with her app, which tells her that the woman seated on the other side of the bar is indeed over 21. None of the customer’s personal information, such as her name, birth date, or address, is displayed or stored on the bartender’s phone.

Given the the need exists, the vision exists and the implementation is demonstrably feasible, perhaps the trigger of Brexit can give us the digital identity infrastructure that our nation so desperately needs and the lack of which is such a source of friction and inefficiency.

Security and privacy

This is a way to deliver an identity scheme that provides both more security and more privacy. It does not need a big database with everyone’s details and it does not need expensive, custom-built, specialist equipment. In that 2005 piece for Prospect magazine I argued that that the government’s vision for the proposed ID card scheme was tragically out of date and backward-looking. Even the pressure group No2ID were nice about me, saying that that I was someone in favour of an ID scheme who actually knew what I was talking about but “unfortunately his preferred scheme is incompatible with the Government’s plans”. Indeed it was, but that didn’t matter because the scheme was scrapped by the next government anyway.

Writing about this kind of entitlement scheme a few years ago, I thought that a national plan to finally do something useful about identity might obtain “parasitic vitality” (to use one of my favourite ID phrases) from the specific issue of voter ID. Maybe electronic voting could have been a focus to get the gov.verify scheme a flagship project  and get the public and private sector working together to deliver an infrastructure that will be of benefit to all. None of this ever happened and gov.verify has gone, essentially, nowhere. So why am I still going on about this! Well, David Goodhart’s new report and other media comment has set me thinking that Brexit might finally provide the stimulus needed to develop the world’s first 21st century identity scheme. Not digitised identity, but real digital identity. Implemented correctly, it could make the UK a better place to work and play in a relatively short time.

* Bona Fides, for those of you who went to state schools as I did, is a Latin phrase meaning “good faith”. My dictionary definition says that bona fides documentary evidence showing that a person is what they claim to be. Note not who they claim to be, but what they claim to be. It gives the usage “credentials, as in he set about checking Loretta’s bona fides”. I’ll go and register the domain “” right now.

CBDC is a black and white issue

I was reading J.P. Koning’s excellent paper [PDF] on Central Bank Digital Currency (CDBC) for Brazil and came across his reference in passing to Narayana Kocherlakota, former CEO of the Federal Reserve Bank of Minneapolis, who wrote (in 2016) that economists do not know very much about the topic of anonymity and “calls for the profession to model it more systematically”. I think this is a really critical point, because the decision about where to set the anonymity dial for a cash replacement product is an important one, and not one that should be left to technologists.

This decision is discussed in the context of implementing a digital fiat currency of one form or another. The paper explores three ways to implement a CBDC for Brazil.

  1. MoedaElectronico (Electronic Cash): this is the most cash-like of the three CBDCs. It pays neither positive interest nor docks negative interest and is anonymous. Like cash, it is a bearer token.

  2. ContaBCB (BCBAccounts): this is the most account-based of the three templates. Ac- counts are non-anonymous and pay interest, like a normal bank account.

  3. MoedaHíbrida (Hybridcoins): provides a mix of cash and account-like features, including the ability to pay a varying positive and negative interest rate, while offering users the choice between anonymity or not. 

Now, the first two are well-known and well-understood. I wrote about them again last month (I’ve discussed “BritCoin” and “BritPESA” several times before), in a comment on Christine Lagarde’s speech [15Mb: Central banks, tokens and privacy] and I don’t propose to look at them further here. It’s that last example that interests me.

Let’s go back to that point about anonymity. In the paper J.P. says that the case can also be made for a permanently negative interest rate on anonymous CBDC. Why? Well, since we all understand that criminality and tax evasion impose costs on society, it may be worthwhile to design anonymous payments systems in a way that recoups some of the costs these activities impose.

In other words, construct a cash replacement in which anonymous transactions cost more than non-anonymous transactions. One way to do this, which is referenced by J.P. in his paper, was the “Crime Pays System” or CPS as conceived by the artist Austin Houldsworth. Austin is most well-known for designing the cover of my book “Before Babylon, Beyond Bitcoin” of course, but he also ran the Future of Money Design Award for Consult Hyperion’s annual Tomorrow’s Transactions Forum for many years. Oh, and he was awarded a Ph.D by the Royal College of Art (RCA). It was his idea to have me present CPS at the British Computer Society (BCS). We had my alter ego set out the new payment system to an unsuspecting audience who, I have to say, were excellent sports about the whole thing! It turned out to be an entertaining and enlightening experience (you can read more and see the video here).

Cps bcs

In CPS, digital payments would be either “light” or “dark”. The default transaction type would be light and free to the end users. All transaction histories would be uploaded to a public space (we were, of course, thinking about the Bitcoin blockchain here) which would allow anybody anywhere to view the transaction details. The alternative transaction type would be dark. With this option advanced cryptographic techniques would make the payment completely invisible with a small levy in the region of 10% to 20% would be paid per transaction.

The system would therefore offer privacy for your finances at a reasonable price. The revenue generated from the use of this system would be taken by the government to substitute for the loss of taxes in the dark economy.

What a cool idea.

Now, at the time it was just a concept. We didn’t spend much time thinking about how it would actually work (I was basing the pretend implementation for the BCS presentation on Chaumian blinding a la Digicash, hence this gratuitous picture of me influencing David in Vegas.)

David Chaum las vegas 2018

That was then. In the meantime, however, along came ZCash and the mechanism of shielded and unshielded transactions that J.P. has used as the basis for MoedaHíbrida’s two different modes. If the user decides to hold shielded (ie, dark) MoedaHíbrida tokens, then all transactions made with those tokens are completely anonymous and untrackable. The user can decide to unshield his or her MoedaHíbrida tokens so that all transactions can be seen (ie, light).

Offering users the choice of anonymity but making them pay for is a radical solution but I’m with J.P. in thinking that it deserves attention. What I think is very clever about using negative interest rates (which had never occurred to me) is that it allows for anonymous transactions without imposing a transaction friction, thus providing the cash substitute in the marketplace, but it penalises the stashing of anonymous cash. The negative interest rate means that dark tokens will be subject to a negative interest rate of, say -5% per annum, while light tokens will receive a competitive SELIC-linked interest rate.

Whether or not this is the way forward I or not, it is a line of thought that deserves serious examination in the context of CBDC design. If it is considered important to society to provide anonymous means of exchange, then the “tax” on the anonymous store of value seems a reasonable way to distribute the costs and benefits for society as whole.

We need to go cashless, not drift into cashlessness

Having just been to China for Money2020 and having experienced at first hand the operation of a cashless society, I’ve even thinking (again) about the design of cash-replacement payment systems for a range of perspectives, using China as a case study. The first point to make is that people in China are well aware of what happens to when society switches from anonymous cash to not-anonymous (I can’t think of a suitable antonym) electronic payments. As observed in the Financial Times, “that scale of data accumulation is beyond our imagination”. The Chinese woman making this comment (while observing that despite her concerns about privacy, mobile payments are too convenient to opt out of) goes on to say (somewhat poetically, in my opinion) that she cannot tell whether her compatriots are “constructing a futurist society or a cage for ourselves”

Not everyone in China is part of this revolution, of course. The World Bank Global Findex database, which measures financial inclusion, estimates that as of lat year some some 200 million Chinese rural citizens remain unbanked, or outside of the formal financial system. As in Sweden, the shift toward cashless is raising issues around exclusion and marginalisation.

There are, for example, supermarkets with different lanes for cash or cashless payments that act as physical manifestation of social stratification between, as Foreign Policy notes, the young and the old and between the urban middle class and those left behind (between, as David Goodhart would put it, the “anywhere” and the “somewheres”). I’ve written before that we will see the same in the UK as cash vanishes from middle class life to become the preserve of the rich and the poor who will use it for tax evasion and budgeting respectively. A “Which” survey found that over 75% of low-income households rely on cash, as well as over 80% of elderly households. The shift to cashless society must be planned to help these groups so that they share in the benefits of cashlessness.

Woking going cashless

Cash is vanishing even in Woking.

I think we should start to plan for this now. In China, as in Sweden (where the New York Times observes that “cash is disappearing in the country faster than anyone thought it would“), we are beginning to see what happens to societies that slide into cashlessness. I am against this. That is, I am in favour of cashlessness, but I am in favour of it as a policy decision by society that is implemented to meet society’s goals. I couldn’t disagree more with the Wall Street Journal’s view that the move to cashless society “should be left to technological advancement”. No, it should not. This is a matter of great importance and with significant implications for society. The strategy should therefore be set by society, not by technologists.

Now, clearly, technological advances deliver new possibilities to policymakers and it is good for technologists to explore these possibilities. But, as they say, just because something can be done does not mean it should be done. We need a proper debate and a regulatory envelope set out to move forward. I wonder if we might seize the opportunity and set down a technological marker for post-Brexit Britain by declaring that cash will be irrelevant in the UK in a a decade. That is, anyone who needs to pay for anything will be able to do so electronically and that anyone who does not want to pay electronically will be presented with a method for paying in cash, albeit one that they have to pay for like (like cheques).

This must mean that in parallel we must set a national goal to provide a free at the point of use electronic payments infrastructure for everyone. Otherwise we’ll end up where they are in America, where jurisdictions are trying to ban cashlessness (and thus keep the cost of the payment system high, especially for the poor) in the name of social justice. In New York, Congressman Ritchie Torres has put forward proposals to force businesses to accept cash and called them a a “new frontier” of anti-discrimination law that is needed to prevent a “gentrification of the marketplace”. Similarly, as the Washington Post reports, lawmakers in the nation’s capital have introduced a similar bill. A council member there said that by refusing cash businesses are “effectively telling lower-income and younger patrons that they are not welcome”. Maybe, but if so it’s only because those demographics don’t spend enough to provide the margin needed to cover the cost of cash.

It’s time to start thinking about what the requirements for that infrastructure are and consulting consumer organisations, businesses and government departments on their needs. We need to make a cashless Britain, not simply allow a cashless Britain.