An unprecedented federal review of old criminal cases has uncovered as many as 27 death penalty convictions in which FBI forensic experts may have mistakenly linked defendants to crimes with exaggerated scientific testimony, reports the Washington Post. The review led to an 11th-hour Mississippi stay of execution in May. It is not known how many of the cases involve errors, how many led to wrongful convictions or how many mistakes may jeopardize valid convictions.
The review could become a factor in the debate over the death penalty. Opponents say the execution of a person confirmed to be innocent would crystallize doubts about capital punishment. But if DNA or other testing confirms all convictions, it would strengthen proponents' arguments that the system works. FBI officials discussed the review's scope as they prepare to disclose its first results this summer. The death row cases are among the first 120 convictions identified as potentially problematic among more than 21,700 FBI laboratory files being examined.