(CNN) -- Rubin "Hurricane" Carter is too old to box these days. He doesn't even watch it and thinks it's "sort of barbaric."
His days as a pugilist left him when the fight to clear his name in a Paterson, New Jersey, triple murder overtook his quest for world championship belts.
"When I went to prison in 1966, that was it for me as far as prizefighting was concerned," said Carter, 73. "I was fighting for my life, not for a prize in the ring and not with boxing gloves and referees. I was fighting for my life in the absolute dungeon called Trenton State Prison."
Though he's still dogged by those who claim he's guilty, Carter was released from prison in 1985 by a federal judge who wrote, "A conviction which rests upon racial stereotypes, fears and prejudices violates rights too fundamental to permit deference to stand in the way of the relief sought."
In his latest book, "Eye of the Hurricane: My Path from Darkness to Freedom," Carter explains he's not perfect and concedes guilt to a host of regrettable crimes -- including assaults and robberies but not murder.
Those crimes, he said, were perpetrated when he was blind, operating unconsciously -- a recurring theme in his book -- and they were the product of the anger to which he succumbed growing up under Jim Crow, he said.
Despite his present activism in defense of the wrongly convicted, social consciousness eluded him during his days in the ring. His refusal to join the Rev. Martin Luther King Jr. for the Selma marches stands as evidence.
Forty-six years later, Carter feels he made the right choice because joining the marchers would have been suicide, he said.
"I was the prizefighter at that time. I was the angry person, and I wasn't going for any of that kind of stuff," he said. "I knew that if I went to Selma, Alabama, and the police force would attack me and put dogs on me and things of that nature, I would have to fight back. ... I would have to defend myself, and I would be murdered down there, and nobody would care."
He wouldn't prescribe it for others, Carter said with a chuckle, but prison is what ultimately allowed him to shed the illusions and anger that spurred his delinquency. Prison is also what helped him realize that his destiny could lie in lacing up his gloves to fight for others.
First, he had to scrap his way out of prison.
"Hatred and bitterness and anger only consume the vessel that contains them. It doesn't hurt another soul," Carter said. "If I were to allow myself to continue to feel that anger and the bitterness of being a victim, I would have never survived prison itself. Prison can deal with anger; prison can deal with hatred because prison is about all those things. So I had to overcome those things."
There was a time when boxing enthusiasts were giddy about Carter's future. He was fast and powerful, hence his sobriquet, and despite being short for his weight class (5-foot-8), he became a Madison Square Garden and television fixture.
Ring magazine declared him one of the top middleweight contenders in 1963 after he knocked out 11 of his first 15 professional opponents.
"His shaven head, prominent mustache, unwavering stare and solid frame made him an intimidating presence in the ring decades before such a look became commonplace," according to the New Jersey Boxing Hall of Fame.
Following a loss in his only title bout in 1964, Carter precipitously fell from grace, losing seven of his 15 final matches before being fingered in a 1966 triple homicide at the LaFayette Bar and Grill.
He was convicted and sentenced to three life terms the following year. The ruling was later overturned, but Carter was convicted again in 1976, a year after Bob Dylan co-penned a song declaring his innocence. That conviction, too, was tossed out, and in 1988, a Passaic County prosecutor filed a motion to dismiss the charges.
Carter walked out of prison in 1985 a cause célèbre. In addition to the Dylan tune, his case had drawn the attention of his heavyweight counterpart, Muhammad Ali, and actor Burt Reynolds, among others.
His plight has also inspired at least a half-dozen books, including his own autobiography, written from prison. A major motion picture that opened years after Carter's release would earn actor Denzel Washington his fourth Oscar nomination.
The 1999 film played a key role in introducing Carter to an audience who had not followed his two-decade legal saga, but the ex-boxer said Washington, in a way, also introduced him to himself.
Carter had interviewed several actors to play him in Norman Jewison's "The Hurricane" -- Samuel L. Jackson, Lou Gossett Jr., Isaac Hayes, Wesley Snipes -- but became smitten with Washington over a meal in Toronto, where Carter had moved after prison.
Returning from a bathroom break, Carter found Washington at the front of the restaurant, gesturing to himself in the mirror. When the actor returned to the table, Carter experienced something he said he can describe only as falling in love. He loved Washington's vocabulary, his attitude, the way he laughed.
For a moment, he wondered whether prison had changed him, made him soft, but "then it hit me like a double left hook and a straight right cross": Washington had already taken on the character of Rubin "Hurricane" Carter.
"Denzel Washington was only an actor doing his utmost to sell himself for a role that he wanted, but my feelings, my likeness sitting across that table showed me how far I had come from self-hatred to the love of self," the former prizefighter said. "What a wonderful experience that was."
Carter realizes most wrongfully convicted prisoners don't have heavyweights like Washington or Ali taking up their causes. Since leaving prison, he has traveled the world taking part in various innocence projects. He headed the Association in Defense of the Wrongly Convicted for 12 years and founded Innocence International in 2004.
He encourages people never to speak to the police if they're arrested and lashes out at false confessions, which he says have become the scourge of the justice system since DNA became a primary tool for establishing innocence or guilt.
He once boxed to make a living -- because, he said, blacks in the 1940s and '50s had few options outside being a criminal or entertainer -- but he fights today because innocent people in prison rarely have anyone in their corner.
"The system does not like people who say they're innocent in prison, but there has to be a way for innocence to survive in prison," he said. "Prison is the lowest level of human existence (you) can exist on without being dead. ... Being able to overcome that, that's the miraculous nature of every human being. It is great, absolutely fantastic."