So Cullen created a pamphlet and mailed it to all the men’s prisons in Oklahoma. He said those who are incarcerated spend a lot of time writing letters without receiving a reply and that they often had little to no awareness of organizations focused on proving innocence after a conviction.

“I figured word would get around, and it did,” he said. “I spent a lot of time vetting letters. I had just enough experience in the criminal justice realm to kind of be able to tell what a good case was and what wasn’t.”

Then a letter from Scott arrived in the mail, followed by Carpenter’s about a week later. What would follow was 10 years of pro bono work on their case and their eventual exoneration and release, also in Holmes’ courtroom, after another person confessed to the crime before being executed in an unrelated murder case.

“I knew they were co-defendants. I thought, ‘Did they sit down next to each other and write this?’” Cullen said of Carpenter and Scott. “And then I learned that wouldn’t be possible because they went to prison as co-defendants and they can never be in the same prison. And that really spurred me on. So that’s what got me into it.”