Errors at F.B.I. May Be Issue in 3,000 Cases
The Justice Department has identified about 3,000 criminal cases that could have been affected by flawed procedures and skewed testimony by F.B.I. laboratory technicians before 1997. It is letting prosecutors who handled those cases decide whether defendants should be notified.

Government officials said they were aware of 100 to 150 cases in which prosecutors had alerted defendants to problems that might have affected their verdicts. None have resulted in overturned convictions, they said.

One of the cases has reached the Florida Supreme Court. The court ruled last week that a convicted murderer, George Trepal, was not entitled to a new trial, despite evidence that the F.B.I.'s chief toxicology chemist gave inaccurate testimony.…
http://www.nytimes.com/2003/03/17/politics/17FBI.html