Brian Nelson was haunted by his experience of being locked in solitary confinement for 23 years in Illinois prisons.
After he was freed in 2010, he dedicated his life to helping other inmates.
Mr. Nelson, 56, a former Chicago gang leader, became an advocate for the rights of men and women in prison. He worked for the Uptown People’s Law Center in the 4400 block of North Sheridan Road.
His prison years left him anxious, so he usually worked alone on the second floor of the center.
On Monday night, he was found dead in his office with a pile of letters from prisoners on the desk in front of him, said Alan Mills, executive director of the Uptown People’s Law Center.
“He finally found some peace,” Mills said.
Autopsy results are pending.
During his decade working at the center, Mr. Nelson answered thousands of letters from inmates. They provided lawyers with valuable details as they prepared lawsuits on behalf of prisoners.
Mr. Nelson also took calls from people just released from prison and advised them how to stay out of trouble.
“I didn’t want them going back to prison for smoking a joint,” he once said.
Some knew of Mr. Nelson through his 2019 interviews with the Chicago Sun-Times and WBEZ-Chicago for the “Motive” podcast in which he told a harrowing story of life in prison and his struggles to maintain his sanity after he was freed.
“I spent 28 years in prison, 23 years in solitary confinement for a murder I was involved in when I was a kid,” said Mr. Nelson, who was paroled in 2010.
The last decade of prison was the worst: solitary confinement at a super-max prison, Tamms Correctional Center, in southern Illinois.
While at Tamms, Mr. Nelson said, he copied the Bible word for word.
“One year, two months and nine days, it took me,” he said.

Brian Nelson showing the pen he used to copy the Bible in longhand while imprisoned at now-closed Tamms Correctional Center, where he spent 23 hours a day in isolation.
Richard A. Chapman / Sun-Times file
He kept the thick sheaf of paper in a box in his office.
At Tamms, he paced his cell for hours, till his feet bled. His weight dropped from 178 pounds to 108. He kept spiders for companions.
Mr. Nelson credited Mills with getting him out of Tamms.
“I played a part in it,” Mills said. “I fought for him for the whole time he was there.”
For years, advocates for prisoners called for the state to close Tamms, saying it inflicted lasting psychological harm that amounted to “cruel and unusual punishment.” It was shut down in 2013.
Mr. Nelson later gave written testimony to the U.S. Senate at the request of U.S. Sen. Dick Durbin, D-Illinois, describing the damage his forced isolation at Tamms did.
He also testified before the Illinois House Judiciary Committee, calling for an end to solitary confinement in other Illinois prisons.
“I think Brian played an important role in a national movement to abolish solitary,” Mills said. “I don’t think people understand how much that took out of Brian in reliving the trauma.”
While he was a leader in the Simon City Royals street gang in prison, Mr. Nelson’s nickname was Mousey. But he disliked being called that after he was free.
“I do everything to make sure I don’t go back to jail,” Mr. Nelson said at the Uptown People’s Law Center in an interview for “Motive.”
“I got a house,” he said. “I have a job. Out of 100 of us from Tamms, only three of us do. Other guys can’t cope. A lot of times, I can’t cope. I don’t think I belong out here. I know how to be alone in a box. I work alone upstairs. Nobody comes up there. My first office here was the same color as my cell in Tamms. And about the same size.
“What happened to me in prison was wrong.”