According to the Death Penalty Information Center, Mr. Hinton is the 152nd person exonerated from an American death row since 1973.

“Cases like Anthony Ray Hinton’s give the public pause about the death penalty,” said Robert Dunham, the center’s executive director. He added that “from the outset, this case exhibited many of the classic signs of innocence.”

Mr. Hinton, 58, argued for decades that Alabama officials — including the judge who oversaw his trial and is now retired — had made a series of compounding mistakes after three shootings in 1985 that left two men dead and another wounded. They began, he said, with his arrest in one shooting that occurred while witnesses said he was at work miles away. Officers had retrieved a handgun from Mr. Hinton’s home and, after analyzing it and the recovered bullets, concluded that the shootings were tied.

Mr. Hinton, 29 then, was indigent, and the Supreme Court said last year that the lawyer appointed to represent him, Sheldon C. Perhacs, had mistakenly believed he had only $1,000 to hire an expert witness for the proceedings. Mr. Perhacs’s choice — a man later described by a prosecutor as a “one-eyed charlatan” — did little to help the defense, and Mr. Hinton was convicted and sentenced to death.

It took almost a decade for Mr. Hinton and his lawyers to recruit a panel of experts, including a former F.B.I. official, to review the forensic evidence. The panel questioned the findings of the Alabama authorities, but the state remained steadfast. In 2003, for instance, the Alabama attorney general said, “The experts did not prove Mr. Hinton’s innocence, and the state does not doubt his guilt.”

All the while, Mr. Hinton remained at a prison in south Alabama, awaiting his execution.

“I witnessed other inmates’ time run out,” he said, “and I’d be lying if I said you don’t ask yourself, ‘Wow, is that going to happen to me?’ ”

But last year, the Supreme Court said that Mr. Hinton’s defense had been unacceptable, setting up a new trial and essentially forcing prosecutors to review the evidence for a case in which they acknowledged the forensic studies were paramount.