In the mid-1970s, Walpole State Prison had the highest murder rate of any prison in the country, and the lowest conviction rate: zero. The District Attorney's office had been pilloried by the press for its inability to get results.So when a particularly atrocious murder occurred on Thanksgiving Day, 1976, and an inmate offered to testify that he'd seen who did it, DA William Delahunt jumped at the offer.The DA's office and state police framed Stephen Doherty for the crime. It took him twenty years to prove that he was innocent.This is his story.