The FBI has identified for review roughly 2,500 cases in which the FBI Lab reported a hair match before 2000, when DNA testing of hair was routine. So far, reviewers have found that FBI examiners gave flawed testimony in 257 of 268 trials in which hair evidence was used again criminal defendants. Read the related article

284 defendants account for the 257 cases with error. There are 231 state convictions and 53 federal convictions.

SOURCE: National Association of Criminal Defense Lawyers and Innocence Project analysis of FBI and Justice Department data, as of March 2015. Published: April 19, 2015.