Why I am against biometric ID cards

Charles Arthur

DNA sampling

Only people who have been arrested are placed on the DNA database. Photograph: Press Association

Can you support Britain’s current DNA database yet oppose plans for biometric ID cards? That’s the question I’ve been wrestling with this week. The answer, as you’ll see, isn’t trivial.

The past week has seen three men convicted of murder, and all three were either convicted or suspected of multiple killings. In two cases, DNA evidence proved vital: their DNA had been acquired through the current procedure whereby if someone is arrested his or her DNA is taken and recorded (as a set of 20 numbers) on the national database. Previous crimes where DNA has been recovered but no other match found are then checked against new entries.

And DNA, being almost the ultimate biometric, is very indicative. There are even cases that have been solved because someone has given a DNA sample and the database has suggested that someone related to them has a link to an unsolved crime.

It is beyond argument that the database is a fantastic tool for solving crime. I think it is also right that arrest should be the trigger for taking a sample, since it’s logical that someone who has committed a serious crime will probably commit smaller ones too. (And that’s why I’m against the case currently being brought by two people who were arrested but not charged and want their DNA details removed from the database. Arrest may be a weak indicator, but it’s still an indicator.)

False convictions

Equally, I’m against widening DNA collection to the whole population. The reasons were elegantly spelt out in The Guardian on Thursday by Professor Allan Jamieson: “The larger [the database] becomes, the greater the chance is of a fortuitous ‘hit’, false conviction, and unnecessary stress on individuals and resource deployment by the police.” And since the Home Office minister Tony McNulty agrees, I don’t think there’s much risk of the DNA database encompassing all of us.

OK, but what about biometrics – iris scans, fingerprints, facial recognition – for ID cards? After all, consider benefit fraud, which is estimated to have cost the taxpayer £2.5bn in 2006/7. There’s an interesting exchange in last year’s Hansard in which a minister for the Department of Work and Pensions says that “the introduction of identity verification services, to be provided by the Identity and Passport Service as part of the National Identity Card scheme, will have a significant impact on the ability of fraudsters to make claims for social security benefits using more than one identity.”

That’s fine – except that in an earlier question in that exchange, Derek Wyatt asks what estimate has been made of how much could be saved by having a verifiable national database of addresses (which presently doesn’t exist). The minister replies: “There has been no estimate made of the value of fraudulent claims which could be detected annually if a definitive national database of addresses existed.”

So it’s one of those things where the government has only worked out the answers to the questions it likes, rather than all the possible answers. It’s a long way from what you’d call “science” – or even rigour.

Ludicrous and expensive

More to the point, an ID card would be used to prevent benefit fraud – not to prove who committed the crime after the fact. If you had to give an iris scan when making each benefit application, that would make multiple fraudulent applications harder. The fact that one woman could claim for an amazing 18 non-existent children doesn’t suggest that the system for detecting unusual claims is very robust at the moment. But making parents and children come to an office for iris scans and fingerprinting before they can get child benefit would create a ludicrous, expensive system that could still be gamed (what about children visiting from abroad? You’d have to iris-scan and fingerprint everyone).

It is that presumption of guilt, though – the thinking that you’re only out to cheat the system – that seems so wrong about the national biometric database. Leave aside the issue of how secure it might be. Nobody can change your biometrics, just as they can’t change your DNA, so it’s actually rare in being a database you could happily stick on CDs and post around the country. The key is that it assumes you’re guilty. And that’s what I don’t like.

The point about the DNA database is that it only comes into play after a crime has been committed, and when someone is suspected of it. At that point, you become a suspect in all unsolved crimes with DNA evidence. (And perhaps others where your details might match those from other crimes.)

But in claiming benefit, or trying to board an aeroplane, we’re not committing a crime. And in a society that likes to call itself “free”, the presumption of innocence is surely the most important title we can give everyone, even if it is disappointed by fraudsters and killers. It has been the bedrock of our legal system for centuries.

And that, in short, is why I support the DNA database, even for suspected criminals, but do not support a nationwide biometric database. Innocent unless proven guilty is an important freedom. Let’s stick with it.