The retention of innocent people's DNA on the national database undermines the relationship between the police and the community, a Labour MP has said.
Diane Abbott (Lab, Hackney North and Stoke Newington) gave evidence to the home affairs select committee this morning.
She told the committee she objected to the "random" way DNA profiles are collected and the difficulty people have in getting their information removed from the database.
Abbott gave the example of a young woman arrested in Primark when she tried to return items for which she had a receipt. She was arrested and her DNA sample was taken yet she was later released without charge.
That sort of incident "does not build confidence in the community", Abbott said.
In 2008 the European Court of Human Rights ruled the DNA database in England and Wales is illegal because it allows police to indefinitely retain the profiles of people who had been arrested but not charged or convicted.
The government proposes allowing retention for six years.
Isabella Sankey, policy director at civil liberties group Liberty, told the committee that getting police to remove the DNA of innocent people from the national database is "extremely difficult".
It is usually only removed in cases where the arrest was unlawful.
"The bar is exceptionally high but the more high-profile the case, the more likely the deletion," she said.
Sankey said in 2007/08, 172 profiles were deleted and in 2008/09, 283 were removed from the database.
Abbott pointed out that 77 per cent of black men under the age of 25 have their DNA retained.
David Davies (Con, Monmouth) said people who are arrested are more likely to have committed a crime and pointed out that at present only five to ten per cent of reported crimes result in a conviction.
Sankey said that Liberty believes there are exceptional circumstances where there could be retention of DNA of people who have not been convicted of a crime.
She pointed out that the police can re-take DNA samples.
"Innocent people should have their DNA deleted as a matter of course," Sankey said.
Abbott said that "no-one objects to keeping the DNA of guilty people" but the question was about when to keep the DNA of the innocent.
She suggested that a court could direct that DNA be kept and that there should be retention in certain crimes such as those of violence or rape.
Abbott said many lawyers do not think the government's proposal to retain DNA for six years would comply with the European court's ruling on the issue.
She added that there is no conclusive research that keeping the DNA samples of innocent people has led to an increase in the detection of crime.
Bob Russell (Lib Dem, Colchester) asked if it would be better to keep everyone's DNA on record.
Abbott replied that while that option is "intellectually coherent" in practice it would be a huge and unwieldy project to undertake. She said it would be better that the rules around retention of the DNA of innocent people be codified.
At present individual chief constables ultimately decide whether or not to remove DNA from the national database.
Ann Cryer (Lab, Keighley) said that system has led to "patchiness" in some areas and floated the idea of a national agency to deal with the matter.
Sankey said that taking everyone's DNA would not be proportionate or necessary and would lead to more mistakes and bad matches, compromising the whole system.
She pointed out the UK already has the largest DNA database in Europe and the largest in the world per capita.
Chris Sims, chief constable of West Midlands police and the Association of Chief Police Officers lead on the DNA database, told the committee that 33,000 cases a year are detected "solely or largely" through the database.
There were 4.9m crimes a year reported and 1.3m are detected. Fingerprints led to 45,000 convictions.
He pointed out that most of those crimes involve minor incidents that are dealt with locally and rely on traditional policing methods.
Sims said that "for serious and significant crimes" it is much more useful and up to 40 per cent of burglary convictions are secured with DNA evidence.
He said that "not enough is said about the degree to which innocence can be proved by forensic science".
Sims said that 83 murders and more than 160 rapes were solved last year because of the DNA database.
Gary Pugh, ACPO spokesman on the DNA database and a senior forensic scientist, told the committee that the retention of DNA for six years is based on analysis and is the "optimum time".
He said a "significant number" of people who come into contact with the police go on to commit other crimes.
Pugh said it costs £30 to £40 to put a person's DNA on the database.
He said the "over-representation" of black and ethnic minority citizens in the criminal justice system and the database is a concern.
"The database is not inherently prejudiced," he told the committee.
"We are engaging with different communities to explain the ethnic mix of the database," Pugh added.
