DNA expert slams Government

The professor who developed genetic fingerprinting slammed ministers earlier for wanting to retain DNA profiles of innocent people on the UK’s national database.

The database is the largest in the world, holding five million profiles, some 850,000 of which are from innocent people.

“If my DNA were to be put on the database I would object profoundly against that,” said Sir Alec Jeffreys at a hearing of the Home Affairs Committee.

“What advantage is it to me, as an entirely blameless citizen? The best outcome is that my DNA would sit there cluttering up a fridge and that my DNA profile would sit there cluttering up the database.

“The worst that could happen is that there is some glitch in the database that made a false match to my DNA profile and that brings me into the frame of a criminal investigation which has very serious repercussions.”

He said that if, when first developing the process, he’d known a database would be used by the Government in the way it has, he’d have been “astonished, perplexed and deeply worried”.

“I’ve always understood that one of the great foundations of English law was a presumption of innocence, but obviously now there is a presumption of future possible guiltyishness,” he said.

Prof Jeffreys acknowledged that the chances of a DNA sample from a crime scene being wrongly matched to someone’s profile on the database could be between one in a billion and one in ten trillion.

But he went on to explain: “That’s about a million times less likely than you winning the lottery, but every week someone wins the national lottery.

“Now if you look at the ‘lottery’ of the national DNA database, we have five million players there and you run the ‘lottery’ tens of thousands of times a year by doing searches across them.

“So even for matches down to the one in a trillion level, false matches start becoming likely after that.”

The expert pointed out that false matches between family members – who share similar DNA profiles – were even more likely, with the probability narrowing to one in 200,000.

He said only profiles of the guilty should be retained. The Government is bringing in new rules that will allow them to retain the data of innocent people for between six and 12 years.