Before 2000, the FBI’s forensic unit gave flawed testimony in almost every trial for two decades, the Justice Department and FBI admitted. A total of 26 out of 28 examiners in the unit overstated forensic matches for microscopic hair comparison in 95 percent of the 268 trials reviewed so far. 32 of those include defendants sentenced to death, 14 of whom have already been executed or died in prison. The government is being assisted in a post-conviction review by the National Association of Criminal Defense Lawyers and the Innocence Project. The errors do not mean, however, that there was no other evidence to convict the criminals.