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Precrime in Camden: using DNA profiles for crime prevention

The UK police has an estimated 5.3 million DNA profiles in its databases, of which about 850,000 are of people who were never convicted of any crime (including 24,000 samples of youngsters who have never been convicted, cautioned or charged with any offence). Although the European Court ruled that a policy of retaining profiles of innocent people is illegal, the Home Office seems keen to retain them anyway, at least for serious crimes. Now it is claimed by a police officer that police in Camden deliberately target young people who have not been arrested yet in order to obtain DNA samples. According to him it is part of a long-term crime prevention strategy to discourage future crime. But does pre-emptive acquisition of DNA profiles make sense as crime prevention?

The arrest of innocent youths is problematic because arrests are
usually supposed to be used to  catch criminals, not to collect
evidence for crimes that have not yet been committed.

The claim made by the policeman is that by having a DNA sample before any serious crime has been committed it would discourage future crime since the potential criminal now knew they would be more easily caught. He also claimed that not getting DNA might mean future murders or rape will occur.

This however assumes that the potential criminal is rational and convinced that he cannot avoid leaving DNA traces at future crime scenes, and that the police will correctly profile them. All three assumptions are highly doubtful: criminals tend to be less smart than others, there are reasons to think many prefer risk and many crimes are committed under conditions of lowered rationality. Many crime scenes will mask DNA evidence, and currently there is a noticeable cost to doing a DNA profile of the evidence – it is unlikely to be used in all cases. There is a widespread assumption that DNA profiles are very effective at solving crime based largely on impressions from "CSI", but there is practical fallibility in evidence gathering and lab work. Hence the DNA will not rationally discourage the potential criminal much. They may be emotionally discouraged by the police taking an interest in them and maybe even erronously convinced of the infallibility of DNA, but this does not seem to be much better than giving them the classic stern talking to. It might even backfire, convincing them that they are destinied to become criminals. Overall, the case for preventing crimes this way appears to be weak.

The Home Office claims that removing the 850,000 innocent profiles were removed would result in around 4,500 fewer crimes being solved each year. This is sounds implausible. There are about 5 million recorded offences each year in the UK, 0.08 per person. In a population of 850,000 there should be about 70,000. If 4,500 of these solved thanks to DNA, that would mean that one crime in 15 was solved (not just investigated) using DNA profiles. The majority of crimes are of course minor things like vandalism and theft. Either there is an enormous use of DNA profiles, or (in my opinion more likely) somebody came up with an impressive-sounding number to promote the policy.

If one is to accept the argument that solving future crimes is a sufficient reason to get innocents into the DNA database, then clearly there is no reason (other than economy) to just go for particular Camden youths: everybody should be in the database.

The core issue is whether placing non-suspects into databases breaks the respect for private life or whether there is such a pressing need that the right must be ignored. The European Court thought that it was "a disproportionate interference with
the applicants' right to respect for private life and cannot be
regarded as necessary in a democratic society"
Privacy is by no means a simple right to understand, and its importance and meaning depend on both technology and culture. Hence current views may shift as biotechnology and the reality soap culture evolve. It is not inconceivable that a future society might accept a total lack of privacy if it was also tied to strong accountability (to keep authorities from abusing their power) and tolerance (to avoid conflict or conformism). But most current people would desire privacy since it (among other things) protects against overreaching social control. The problem isn't proper social control – police arresting criminals – but misuses of power, both real and suspected.

The UK DNA database has been used for genetic research without consent, personal information has been retained by non-police actors or stolen, and the Camden affair suggests that police is engaged in extending it in ways that likely break judical practice. This is reason enough to suspect that the database is currently not managed properly.

The solution is not to remove the database (since it is useful for legitimate purposes) but to ensure proper management. The potential intrusion into personal privacy and risk of social
control must be counterbalanced by an equal or larger amount of
transparency and accountability among the agencies involved in
collecting, storing and using the database. There are ways of ensuring privacy by keeping the database encrypted by a trusted third party, logging access and enabling tracking of misuse. The organisation surrounding DNA databases such as the police must be kept under strict oversight not just to prevent improper use, but even the suspicion of misuse. While this might partially be achieved using technological means, much would consist institutional changes (which of course would have to take the privacy rights of employees into account).

The police or any other government agency cannot be said to have a right to privacy. Rather, there is a public interest in exposing them to intense social control where inefficiencies, mistakes and malfeasance can be detected and those responsible held accountable: the organisations and people acting in them have a form of anti-privacy obligation. Hopefully that can keep them on the straight and narrow.

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1 Comment on this post

  1. I assume that the DNA samples were taken lawfully, so the only question is whether they can be kept by the police for some purpose. To me, the only legitimate purpose was that for which the DNA was taken to begin with — law enforcement. In this respect, DNA is very much like other information about a person lawfully obtained. Privacy is always invaded when information about a person is obtained by others but, so long as the obtaining of the information is properly limited in terms of function, there can be no objection to keeping the information, so long as the identity of the person whose DNA it is is not given out. So, for example, letting others use the DNA for research would pose no privacy problems so long as the identity of the person is not disclosed.

    What of studies of persons with certain DNA characteristics in terms of tendencies to particular kinds of conduct? Again, I can see no problem with privacy so long as the identity of those whose DNA is used is kept secret by the police. This is true even if the results of the research make the particular person whose DNA is used in the study more likely to be suspected of particular sorts of crime and therefore more subject to surveillance by police (who, as I assumed, have the DNA sample and the identity of the person whose DNA it is lawfully).

    If, indeed, the actual identity of the person from whom the sample is taken is subject to discovery by accident or by improper use of the sample and disclosure by police custodians of the sample, then the law should be changed in a way that reflects a proper weighing the privacy interersts of the citizens against the importance of the taking of samples to law enforcement, and the costs of better securing the identity of the sample’s donor from discovery.

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