At age 6, Clifford O’Sullivan (pictured with his mother) testified in favor of a death sentence for the man who had killed his mother. That man, Mark Scott Thornton, is on California’s death row. Now, 20 years later, O’Sullivan says he believes Thornton’s life should be spared. When he took the witness stand during the sentencing phase of Thornton’s trial, O’Sullivan told the jury, “All I think is that what the bad man did to my mom should happen to him. It’s really sad for my family ‘cause she was one of the greatest mothers I’ve met.” In the years that followed, O’Sullivan struggled to heal from his mother’s death, experimenting with drugs and alcohol and even committing burglary as a teen. Today, he is an emergency room nurse in Nashville. In an interview with The Tennessean, he says he believes only a “hair-thin” difference in circumstances stopped him from ending up like Thornton. O’Sullivan also has become disillusioned with the death penalty, saying, “It certainly doesn’t do the two things it’s supposed to do. Offer retribution and deterrence.” In 2014, he met Thornton, and the men spent 5 hours talking about their lives. The meeting cemented O’Sullivan’s belief that Thornton should not be executed. “If they put him up for a date I would stop it, just like I started it,” O’Sullivan says. “It wouldn’t happen. Over my dead body.”