After 17 years in prison, Gloria Killian was exonerated for the role she didn’t play in planning a robbery-murder. Joyce Ride, the mother of the first female astronaut, Sally Ride, befriended Killian in prison, and hired a private investigator to look into the case. She ended up spending about $100,000 of her own money on the cause, but the PI uncovered evidence that her accusser (one of the actual perpetrators of the crime) had received leniency to testify against her. The prosecutors had cut a deal with the actual perpetrator to make their case against an innocent woman, and then covered it up. There was also a letter from him admitting he had lied in his testimony. CNN did an in-depth write up, and its worth a read. http://www.cnn.com/2014/03/14/us/death-row-stories-killian/index.html?hpt=hp_c3
Thestory.org has another telling of the story.
Also, Killian has a book.