A man convicted of a 1982 rape in Louisiana's capital city walked free Thursday after 35 years in prison, following his exoneration using an updated fingerprint database.

The Innocence Project, which works to free wrongly convicted defendants, said Archie Williams was freed after his conviction was vacated by a Louisiana district court commissioner, Kinasiyumki Kimble, in Baton Rouge. The organization said in its statement that it had been working to free Williams since 1995.

The group said in recounting Williams' case that he had been prosecuted and convicted despite having an alibi and based largely on an uncertain identification by the victim, who chose him from a photo lineup.

"Nearly one month after the crime, the victim was shown a photo array that included Williams, but she did not select him as the assailant. She did, however, tell police officers that when they look for the assailant, they should look for an individual who resembled Williams' photo," the news release said. It was only after she'd been shown photo arrays three times that she said Williams was the assailant.

Another complication: prosecutors long opposed Williams' efforts to have fingerprint evidence checked against a national database, according to the news release.

However, after Kimble called a status conference to discuss the case last month, prosecutors agreed to a search using an updated FBI fingerprint database, part of its Next Generation Identification system.

That led to a match of fingerprints found at the scene of the 1982 rape and stabbing in Baton Rouge to another man — a confessed serial rapist who died in prison in 1996, according to the Innocence Project.

"If there is potential proof of an incarcerated person's innocence, they must have access to it, no matter how old the case or how many times they have asked before," Emily Maw, senior counsel at the Innocence Project New Orleans, said in the statement. "If Commissioner Kimble had not insisted on, and First Assistant District Attorney Dana Cummings had not agreed to, a fingerprint search, Williams would have died in prison."

Maw said the case points to the need for state laws giving incarcerated people access to evidence that can prove their innocence, allowing court testimony from experts on eyewitness testimony.

The Advocate reports that Williams walked out of the state courthouse in Baton Rouge along with relatives and attorneys, including Innocence Project co-founder Barry Scheck.

"There are many innocent people at Angola," Williams said in Thursday's news release, referring to the Louisiana State Penitentiary at Angola. "Guys who have served over 50 years. I'm happy to be cleared finally, but I'm not free until they are free."