William Dillon, 52, of Chapel Hill, N.C., always knew that singing was one of his talents.
"Back then all we had were cassettes and the radio and I used to sing all the songs," Dillon said.
Singing was his inspiration. He would sing in the car, at school, and in the Florida prison where he spent nearly 30 years for a crime he did not commit.
Tonight he will share that voice, which he describes as soulful and reminiscent of Johnny Cash, with thousands of fans when he sings the National Anthem at the opening of the Tampa Bay Rays baseball game.
He was 21 and living in Brevard County, Fla. when he was arrested and convicted of the beating death of James Dvorak. At the time, he held down two jobs, one as a carpenter's apprentice, the other as a bowling alley mechanic. A formidable baseball player, he was a week away from his second try-out with the Detroit Tigers.
Dillon says he was hardly a likely suspect.
"I was loving life, partying, had not a care in the world," he told ABC News.
A coincidence placed him in Canova Beach, Fla., at the scene of Dvorak's beating several days after it occurred where he was questioned by police searching for leads in the case. They asked him to come down to the station the next day for questioning.
He missed that meeting and, days later, found out that police were looking for him around Canova Beach. He was taken in for questioning and arrested in a matter of days.
Police said that a yellow shirt found at the scene and linked to the murder was Dillon's, and an investigator said a police dog indicated a positive match after smelling the shirt and piece of paper Dillon had handled.
That DNA test was later proven inaccurate and the investigator was discredited after a witness admitted that she and the investigator were having an affair. Though other testimony was unreliable, a jury convicted Dillon and sentenced him to life in prison.
Dillon recalls feeling completely lost upon hearing the verdict.
"I firmly believed in the justice system….I was so young and naïve. It wasn't until I was in prison that I realized I was stuck," he said.
Imprisoned, embattled and clinging to the little hope he had, Dillon turned once again to music.
"It's so sorrowful to sing in a prison because you see all things wasted away," Dillon said. "The music soothed me."
It left him enough fight to agree to file for a post-conviction prison DNA test in 2007, at the recommendation of a fellow inmate, though previous attempts had failed. An organization called the Innocence Project stepped in, a non-profit that helps exonerate innocent inmates through extensive and specialized DNA testing.
"He would have languished and died in that prison," said Melissa Montle, staff attorney for the Innocence Project.
Their tests proved that Dillon's DNA did not match that which was found on the shirt. After 27.5 years, he was released from prison in 2008.
Dillon is now a full-time musician and just released his first album, Black Robes and Lawyers. The title track was first penned in Dillon's jail cell on a scrap of toilet paper.
His songs are guttural, proclaiming patriotism and freedom. Dillon says he still believes in the American dream as well as the justice system, irony not lost on Montle.
"The tagline is the system worked, but it didn't work. If he hadn't fought like heck to get out he would still be in there," she said.
Tonight Dillon will step onto the field, clad in the black "Not Guilty" shirt he wore when he was released, and sing his love song to America.
"I firmly believe in freedom and I believe America stands for freedom. I'm a symbol of hope that things can happen- even if you lose hope you have to keep going on. All they have to do is look at my story. You can't give up."