More than 1.6 million DNA and fingerprint samples of innocent people on police databases must be destroyed after a court ruled yesterday that keeping them breaches human rights.

The landmark judgment by the European Court of Human Rights is a big setback for the Government and police, who insist that storing the records is a key weapon in fighting crime. Ministers have until March to implement the ruling or find a way of retaining records that satisfies the court. Until then none of the records will be removed from the databases.

Jacqui Smith, the Home Secretary, and senior police officers said they were disappointed with the ruling at the Strasbourg court but human rights groups welcomed the unanimous judgment.

In their ruling the court condemmed the “blanket and indiscriminate nature” of powers given to police in England, Wales and Northern Ireland and said retaining the information “could not be regarded as necessary in a democratic society”.

The court said that keeping the DNA samples and fingerprints of people acquitted of offences, or where proceedings were dropped, breached a person’s right to respect for private life. The 17 judges said the retention of the data stigmatised an individual.

It said that the use of modern scientific techniques in the criminal justice system and their potential benefits must be balanced against important private life interests. The judges said that any country claiming a pioneer role in the development of new technologies bore special responsibility for striking the right balance.

“In particular, the data in question could be retained irrespective of the nature or gravity of the offence for which an individual was originally suspected, or of the age of the suspected offender; the retention was not time-limited; and there existed only limited possibilities for an acquitted individual to have the data removed from the nationwide database or to have the materials destroyed,” the ruling said.

The ruling is a victory for two Britons who have been fighting to have their DNA samples removed from the database after police insisted on keeping them.

Michael Marper, 45, was arrested in March 2001 and charged with harassing his partner. His fingerprints and DNA were taken, but before his trial he and his partner were reconciled and the case was discontinued later. Mr Marper from Sheffield, South Yorkshire, had no previous convictions.

In a separate case, a 19-year-old, named in court only as S, was arrested and charged with attempted robbery in January 2001 when he was 12. S, also from Sheffield, was cleared five months later Both asked South Yorkshire police to destroy their profiles but the police refused, saying the details would be retained to “aid criminal investigations”.

Peter Mahy, the solicitor who represented both men, said the result was a “fantastic result after a seven-year hard-fought battle against the UK Government”. He added: “There is a very clear principle here that innocent people should not be disadvantaged in any way.”

Under present laws, the DNA profiles of everyone arrested for a recordable offence in England, Wales and Northern Ireland are kept on the database, regardless of whether they are acquitted or the charge is dropped. In Scotland, DNA is kept on the database for three years if a person is acquitted of a serious assault or sex crime.

Samples of 4.6 million people are on the DNA database – the largest in the world – and 7.5 million fingerprints are held on a separate register.

An estimated 800,000 DNA samples are of people acquitted or whose cases never reached court, because charges against them were dropped or never brought. At least a further 800,000 would have to be scrapped from the separate fingerprint database The Home Office highlighted the benefits of retaining samples of people acquitted of crimes who then go into to commit further offences.

At the end of 2005, samples taken from 14,000 crime scenes including 114 murders, 55 attempted murders and 116 rapes had been matched to 8,500 individuals who had been arrested but had charges dropped or had been acquitted of other crimes, the department said.

Shami Chakrabarti, director of Liberty, welcomed the decision. “The court has used human rights principles and common sense to deliver the privacy protection of innocent people that the British Government has shamefully failed to deliver,” she said.

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