 By 2015 it found that these included 32 death penalty convictions, of which 14 people had died in prison or been executed, and narrowed its review to cases that went to court.It has focused on cases in which hair analysis played a part in convictions, in order to follow up with defendants.In a subsequent investigation in 2012, the DOJ found that evidence related to hair analysis had been falsified, altered, or suppressed, or that FBI agents had overstated the scientific basis of their testimony, to the detriment of defendants.