By Andy Tighe
Home affairs correspondent, BBC News
MP Damian Green has had his DNA profile deleted since being arrested
Innocent people trying to get their DNA records removed from police databases in England and Wales face a postcode lottery, the Conservatives have said.
Figures they obtained show some forces delete the profiles of most applicants, but others refuse to remove any at all.
The average removal rate is only 22%, with six forces not removing any.
Chief Constable Chris Sims, of Acpo, said the police would work with the government to develop clearer guidance over DNA retention.
Last year the European Court of Human Rights ruled that the DNA records of people who had not been charged or convicted cannot be held indefinitely.
In November the government announced new measures to address the court's judgement, which the Home Office said balanced the public's concerns with the operational needs of the police.
Government policy on DNA is a shambles - it is imperative that the police return the DNA of all innocent people.
Damian Green, shadow immigration minister
The measures - including new guidance for police forces - will go before Parliament as part of the Crime and Security Bill announced in the Queen's Speech last month.
The Conservatives and Liberal Democrats have said they would oppose the plan. They argue the system should be the same as in Scotland, which already deletes most of the profiles where there has been no charge or conviction.
Shadow immigration minister Damian Green, who requested the figures under the Freedom of Information Act, said: "Government policy on DNA is a shambles. It is imperative that the police return the DNA of all innocent people."
The forces that did not remove the DNA profiles of any of applicants were Nottingham, Dyfed Powys, Cambridgeshire, City of London, Humberside and Gloucestershire.
Those most likely to remove the information were South Yorkshire and Wiltshire, with 80% or more of requests granted,
see details below
Mr Green managed to reclaim his own DNA from the Metropolitan Police following his arrest in 2008 - as part of an inquiry into Home Office leaks - and subsequent release.
I don't see why it's being retained, for what reason? I have done nothing wrong
But Johanna Upton, a former magistrate from St Leonards in Sussex, has been trying unsuccessfully to get her DNA records wiped for five years.
She was arrested following a misunderstanding over a remark she made about her ex-husband.
Although she was released without charge, Kent Police have refused repeated requests to take her off their DNA database.
"I just feel it's an invasion of my privacy," she said.
"It's not something I wish to share and I don't see why it's being retained. For what reason? I have done nothing wrong."
Anyone who is arrested but not charged or convicted can apply to a Chief Constable to have their DNA records removed, but current guidelines from the Association of Chief Police Officers (Acpo) say it should only happen under "exceptional circumstances".
Chief Constable Chris Sims, an expert on forensic science at Acpo, said DNA was "hugely important in many investigations" but it was also "vital" the database remained "reasonable and proportionate".
The government claims that over the last decade, the DNA database has given the police possible leads on an offender's identity in nearly half a million cases.
Following public consultation it is now recommending a six year limit for retaining the DNA of most unconvicted adults.
Home Office minister Alan Campbell said the DNA database played a "vital role" in preventing crime and "bringing offenders to justice".
Repeat offenders or people convicted of serious crimes would have their DNA profiles held indefinitely.
Unconvicted 16 to 17-year-olds would have them held for six years where they were arrested for a serious offence, three years for arrests over minor offences.
Unconvicted younger juveniles would face a three-year limit.
Last month Home Secretary Alan Johnson said he believed the proposals represented the most proportionate approach to DNA retention, "as well as the most effective way of ensuring the database continues to help us tackle crime".
But the Conservatives say none of the recommendations are yet law and in the meantime leaving so many innocent people on the DNA database is undermining public confidence in the police.
"We need a new policy which is clear and fair," said Mr Green.
"A Conservative government would adopt the Scottish system where the vast majority of innocent people have their DNA removed immediately."
For the Liberal Democrats, Chris Huhne said all innocent people's DNA should be automatically removed when an investigation was completed.
"Police forces that prove reluctant even to respond to requests for removal are damaging their own reputation with the public," he said.
"They are misjudging what will have to happen, regardless of the election result, if we are to comply with the European Court of Human Rights judgement respecting privacy."
DNA profiles removed
City of London
Devon and Cornwall
Source: Conservative Party and individual police forces. Not all forces provided information.
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