A 71-year-old man was released from a Florida prison this week after serving 31 years of a 90-year prison sentence for selling marijuana.

Richard DeLisi rejoined his family Tuesday morning after serving perhaps the longest sentence for a nonviolent inmate convicted for cannabis, according to The Associated Press, citing The Last Prisoner Project which advocated for his release.

In the three decades he was locked up, DeLisi’s wife died, along with his 23-year-old son and both his parents. His adult daughter suffered a paralyzing stroke after a horrific car accident, and he also had two young granddaughters whom he met for the first time this week.

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A photograph shows DeLisi in a leather jacket and a New York Yankees cap wheeling his belongings through a Palm Beach County prison courtyard on his way to freedom.

While sharing tearful hugs with his family, DeLisi said he was grateful, unresentful and eager to make up for lost time, the AP reported.

“I’m a blessed human being, a survivor,” DeLisi said the next day in a phone interview with the AP.

“Prison changed me. I never really knew who God was and now I know and it changed the way I talk to people and treat people,” said DeLisi, who became a mentor to younger inmates, according to the AP. “For me, being there so long, I was able to take gang members from gangs to gentlemen.”

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DeLisi was 40 years old in 1989 when a judge sentenced him to 90 years for marijuana trafficking. But similar convictions at the time typically amounted to a sentence of only 12 to 17 years, according to the AP.

He said he believed the judge was biased and handed down the hefty sentence because he mistakenly believed DeLisi was involved in organized crime as he was Italian and from New York.

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While in prison, DeLisi learned how to read and write, and also launched an organization called FreeDeLisi.com, which is focused on helping other inmates win their release.

“The system needs to change, and I’m going to try my best to be an activist,” he said.

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Chiara Juster, a former Florida prosecutor who handled the case pro bono for The Last Prisoner Project, criticized DeLisi’s lengthy sentence as “a sick indictment of our nation.”

DeLisi also reunited with his son Rick, who was 11 years old when he was sent away but now is a 43-year-old successful businessowner in Amsterdam with a wife and three children.

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“I can’t believe they did this to my father,” said Rick DeLisi. “I can’t believe they did this to my family,” the grieving son said, describing the reunion like opening up an old, painful wound.

“It’s just kind of like torment on your soul for 31 years,” he said. “I was kind of robbed of my whole life so I just appreciate that I can witness it, but on the other hand I feel like isn’t somebody responsible? Is there somebody that can answer to this?”

Information provided by The Associated Press was used to supplement this report.