National Registry of Exonerations. University of Michigan Law School and the Center on Wrongful Convictions at Northwestern University School of Law. May 2012.
This report is about 873 exonerations in the United States, from January 1989 through February 2012. “Exoneration” is a legal concept. It means that a defendant who was convicted of a crime was later relieved of all legal consequences of that conviction through a decision by a prosecutor, a governor or a court, after new evidence of his or her innocence was discovered. [Note: contains copyrighted materails].
http://www.law.umich.edu/special/exoneration/Documents/exonerations_us_1989_2012_full_report.pdf [PDF Format, 108 pages].