Still no evidence to justify DNA retention

The argument over the retention of “innocent” DNA profiles has descended to a new low as the election approaches.

The Government is crowing at the Conservative decision not to block measures on DNA retention in the Crime and Security Bill as it passed through a dying Parliament.
The last-minute decision by the Tories means that the Government’s plan to retain for six years the DNA of those arrested but not charged or convicted of any offence will stand - unless a Conservative Government is elected on May 6, in which case it is pledged to introduce new legislation putting an end to the practice.
The Conservative move came after the Home Secretary, Alan Johnson, threatened to withdraw the six-year retention period from the bill, enabling profiles of innocent people to be stored indefinitely - in spite of a European Court ruling that this is illegal. Rather than see that happen, the Conservatives decided to allow the bill passage and secure the six-year limit.   
The Prime Minister then said that Tory promises to eliminate retention times if elected undermined the party’s claims to be tough on crime. Mr Brown insisted that innocent DNA profiles had solved crimes. Maybe so: but despite repeated requests from MPs and journalists, the Government has refused to release details of 23 cases Mr Johnson claimed last November would not have been solved but for these stored profiles.
Mr Brown referred to the murder of Sally Ann Bowman, a teenager from Croydon, in support of his claims (uncontested by anybody) that DNA is a powerful tool for solving crime. But the Bowman case falls into a different category. Her murderer, Mark Dixie, was identified because nine months later he was arrested after a scuffle at the pub where he worked, and his DNA-profile matched to DNA from the scene of Sally Ann’s murder.
Let’s be clear about the logical flow of events. As soon as an arrestee’s DNA-profile is obtained, it is compared with DNA-profiles from all unsolved crime-scenes. No matter how short the retention period, these initial matches of a new DNA subject-profile to unsolved crime scenes will never be forfeited – unless, which no party advocates, police would be inhibited from obtaining a DNA sample from arrestees.
In the Bowman case, the crucial match was by dint of Dixie’s DNA-profile having been obtained, not to its retention. DNA-detections as in the case of Sally Anne’s murder are not in jeopardy; no changes the Conservatives or the Liberal Democrats would make would prevent such convictions.
Why is the Government proving so bashful about going public with the list? Since these are all cases claimed to have been solved with the help of retained innocent DNA profiles, they have all presumably have been through the courts, and are therefore on the record. The House of Commons Home Affairs Committee called for the details, but was denied them.
There appears no reason why the list should not be published, unless it does not exist, or contains some weaknesses that the Government fears would blow up in its face. The fact that the Prime Minister could not find a single case among the 23 to bolster his arguments last week – but had instead to call in aid Ms Bowman’s mother, Linda – suggests a singular lack of confidence.
The Guardian made its position clear in a leader on Saturday. Accusing Labour of playing “very low politics with crime” it said the Prime Minister had misrepresented the evidence by citing the Bowman case, and ridiculed Alan Johnson’s claims that the Government’s policy was proportionate. It is not, said the Guardian, describing it instead as “unfounded and illiberal”.