Thu
May
28
"The rising odds of DNA false matches" | Comment Is Free
‘A lawyer and genetic scientist has raised the disturbing possibility of false matches being made in the police national DNA database (NDNAD). He suggests that the DNA database – which at the end of September 2008 had 4,343,624, samples, including those from hundreds of thousands of innocent people – is now so large that it is mathematically predicted an innocent person will be matched to a crime they did not commit.’
‘Costello says that it is accepted that under ideal conditions there will be one false match per one trillion checks. He calculates that about 2.5tn comparisons have been made (500,000 [crime scene samples] x 5,000,000 [subject samples] = 2,500,000,000,000) so it is reasonable to expect that at least two errors have occurred.’
