When people accused of a criminal offence are acquitted or the charge is not pursued, should the State be allowed to retain their fingerprints and DNA samples and use them for the purpose of detecting crime? The Grand Chamber of the European Court of Human Rights in Strasbourg heard argument two weeks ago in proceedings that will have important implications for the criminal justice system.

Two cases are before the Court. S was 11 years old when arrested in 2001 and charged with attempted robbery. After a trial he was found not guilty. Also in 2001 Michael Marpur was arrested and charged with harassment of his partner. Thereafter his partner decided not to press charges. In each case DNA samples and fingerprints were taken. In each case the police refused to destroy the material, relying on a power conferred by Parliament to retain it for use in the detection of crime. As seen recently in the case of Steve Wright (who murdered five Suffolk women and whose genetic material was on the database because of a conviction in 2003 for theft), DNA records can provide crucial assistance in providing evidence of guilt of serious crime.

The applicants complain that the retention of their fingerprints and DNA samples breaches their rights under Article 8 of the European Convention on Human Rights which protects private life, read with Article 14 that prohibits arbitrary discrimination. In 2004 the Appellate Committee of the House of Lords dismissed their case. All five judges took the view that any interference with private life was plainly justified by the ability of DNA evidence to identify the guilty and exonerate the innocent. Lord Brown of Eaton-under-Heywood said that the benefits of a larger database were “manifest” and the objections to it “threadbare”. Indeed, Lord Steyn, for the majority, took the view that Article 8 was not even engaged. Only Baroness Hale of Richmond took the more realistic view that the retention of DNA samples needed to be justified.

You can watch the whole of the 100-minute hearing in Strasbourg on the court website (www.echr.coe.int/ECHR). Three points are very clear. First, the case was eloquently argued by Stephen Cragg for the applicants and Rabinder Singh, QC, for the Government, each of whom demonstrated why English advocates enjoy such a high reputation in Strasbourg. Secondly, the issues are much more difficult than the judgments in the House of Lords suggested. Thirdly (as those responsible for devising the procedures for our new supreme court should note), allowing a camera into court to permit webcam viewing does not disrupt proceedings and serves a valuable purpose in informing viewers about the legal issues being addressed by the judiciary.

The applicants have a strongly arguable case. English law allows for the indefinite and blanket retention of genetic material after a person (even an 11-year-old) has been wrongly accused of a crime, without any need for court approval. In Scotland the samples from unconvicted defendants are, after a short period, kept only in the case of those suspected of serious offences and only with judicial approval. In any event, it is illogical for Parliament to impose on innocent people accused of crime and then acquitted a detriment that is not imposed on innocent people who have never been accused of crime. If a database of genetic material is necessary to combat serious crime, it should apply to the whole population.

But the case for the Government nevertheless deserves to succeed. The applicants do not dispute that there was justification for the taking of their samples when they were suspected of crime. To retain the samples is a very limited interference with their private life, involving no practical detriment, especially when there are strong safeguards against any use of the material other than to check for a match to a crime scene. The Government rightly emphasises that the applicants can point to no factual example of any misuse of such information. The European Court should ignore what Mr Singh described as “science fiction” concerns about what might be done with genetic material in the future. Far more significant is the harsh reality that if DNA samples of those not convicted were, as the applicants urge, to be destroyed after a period of time, then if Wright had been charged with the earlier offence of theft but acquitted, the police would not have caught him so soon and he would inevitably have continued to murder more women.

It is therefore proportionate to the legitimate objective of identifying criminals and exonerating the innocent for the State to retain samples that it has legitimately obtained as long as any improper use of the material is prevented. Parliament was entitled to say, like King Lear: “Bring in their evidence.”

The author is a practising barrister at Blackstone Chambers and a Fellow of All Souls College, Oxford

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