More than 300 persons convicted of rape or murder between 1989 and 2003 were later exonerated by new DNA or other evidence that proved their innocence, according to a study by a University of Michigan Law School professor (Samuel R. Gross, et. al. Exonerations in the United States 1989-2003. Journal of Criminal Law & Criminology 95:523-560, 2005.) In most cases their wrongful convictions were at least partially due to false identification by eyewitnesses. How many persons were erroneously convicted or even put to death in the past? We may never know.
The certain knowledge (with the help of DNA evidence) that mistakes were made in the past is fueling widespread reform of our criminal justice system, and thousands of innocent convicts may have their second day in court as a result. Its also prompting legal changes, including requirements in many states that confessions be recorded (to reduce the number of false confessions), and that informants’ testimony be corroborated before it can be used in a courtroom. States are also tightening up their procedures for how witnesses identify suspects in lineups and in photos.
On page 468 of Human Biology 5th ed. I describe the scientific basis for how a DNA sample is used to identify a particular individual. It's nice to see that its being used to protect the innocent, as well as convict the guilty.
