Accuracy of cutting-edge DNA analysis techniques pioneered in New York now in doubt
The lab is the largest DNA crime lab in North America, and tests about 40,000 items a year in criminal cases including murder, rape, assault and weapons possessions
Two techniques for analysing DNA evidence that were once considered cutting edge are now under fire amid questions about their reliability, and criminal defence lawyers in New York have asked a state agency to investigate the renowned lab that once used both methods.
The New York City medical examiner’s lab developed one of the techniques and became a leader in sophisticated DNA examinations partly because of its work identifying the remains of 9/11 victims.
Both techniques have been phased out in favour of new technology. But the lab claims it’s used its forensic statistical tool developed in-house in 1,350 cases over the past six years and used what’s called low copy number analysis in about 3,450 cases over the past 11 years. Once New York was the only lab in the country that used the latter method.
Lawyers for the Legal Aid Society and Federal Defenders of New York asked the New York State inspector general’s office to investigate in a September 1 letter.
We don’t have access to the code – and we can’t tell if it’s accurate or not. We don’t know what’s in the black box
Legal Aid Society lawyer Julie Fry said low copy number analysis is “like making a copy of a copy of a copy. Eventually it’s going to be faded.”