CLAYTON, Mo. (AP) - The St. Louis County prosecutor's office says a pattern of improper analysis in the police department's crime lab by a fired forensic scientist has led to a review of at least 100 criminal cases.
The Post-Dispatch reports the problem stemmed from the scientist conducting what’s known as side-by-side testing, meaning the DNA sample would be next to evidence from the crime scene.
Clayton based attorney Joel Schwartz says DNA testing should be done without other evidence by its side. He said it should be done “in a vacuum” in order to eliminate the possibility that the scientist could interpret the results in a way to match the evidence in front of them.
DNA can be a critical piece of evidence at trial and the people who analyze DNA can make or break a case.
“This is a job where almost all these experts are qualified and they’re very, very good at what they do,” said Schwartz. “The problem is if you have one bad apple it can absolutely spoil the entire investigation, and this is simply a job where you can’t have bad apples.”
The St. Louis Post-Dispatch reports that crime lab supervisors had identified problems with DNA analysis by the scientist more than two years ago, while Robert McCulloch was the prosecuting attorney. Wesley Bell defeated McCulloch last year. Bell's chief of staff, Sam Alton, said Tuesday in announcing the review that staff was not made aware of the issue after the election.
McCulloch described the situation as "just another lie made up by the Alton-Bell crowd to cover their own misdeeds" in a voice message to a Post-Dispatch reporter. The reviewed cases involve DNA evidence.
Information from: St. Louis Post-Dispatch