Dennis Maher served 19 years in Massachusetts prisons for a crime he didn't commit before DNA testing obtained by the Innocence Project proved his innocence and led to his exoneration.

More information:

https://www.brandeis.edu/investigate/innocence-project/dennis-maher.html

http://www.law.umich.edu/special/exoneration/Pages/casedetail.aspx?caseid=3404

https://www.boston.com/news/local/articles/2011/09/04/exonerated_after_19_years_in_prison_dennis_maher_is_just_living_my_life/