NEW ORLEANS -- John Thompson, a former death row inmate who won his release from prison over a case of prosecutorial misconduct against the parish district attorney's office, died Tuesday at 55.

Local prison reform advocate Norris Henderson said a heart attack caused Thompson's death, according to The Advocate New Orleans.

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Thompson was released in 2003 after a judgment against the Orleans Parish District Attorney's Office. He then founded Resurrection After Exoneration, a support and re-entry program for released inmates.