A state prisoner from New Orleans who recently landed at the center of national legal debate about mandatory life sentences for youthful offenders won his freedom Thursday after 31 years in prison.

Orleans Parish District Attorney Leon Cannizzaro’s office agreed to vacate his murder conviction.

George Toca, 47, walked out of Angola State Penitentiary late Thursday, several hours after pleading guilty instead to two counts of attempted armed robbery and one count of manslaughter from a 1984 stickup that ended with his best friend, Eric Batiste, fatally shot outside a convenience store on South Broad Street in Broadmoor.

Toca’s release almost certainly means the U.S. Supreme Court will scrap a scheduled hearing this spring on whether its 2012 decision in a case known as Miller v. Alabama, barring mandatory life sentences for juvenile convicts, is retroactive. The high court in November took up Toca’s case, above others, to settle an issue that affects about 1,000 convicts in Louisiana and three other states that have refused to apply the court’s ruling to older juvenile lifers.

A spokesman for Cannizzaro’s office said the DA will join in a motion with Toca’s attorneys to withdraw the Supreme Court case.

Toca, appearing briefly in Orleans Parish criminal court Thursday morning, pleaded guilty to the manslaughter count under an “Alford” plea, meaning he did not admit guilt but conceded that strong evidence could have led to his conviction..

Newly elected Criminal District Court Judge Byron Williams granted the joint motion in a case that the Innocence Project New Orleans had pursued on Toca’s behalf for more than a decade.

DA’s Office spokesman Christopher Bowman credited a warming relationship with Innocence Project attorneys, along with Toca’s productive years behind bars, for the decision to let him go free on the reduced charges.

Bowman called it “a just outcome,” also citing the vehemence of Batiste’s family in urging Toca’s release and the fact he will remain on parole for another 30 years under the deal.

“In light of all those facts, the district attorney believed he was no longer a public safety risk,” Bowman said. “The District Attorney’s Office ... is not afraid to take a look at older cases.”

Toca, known as “Chicken George,” has long maintained his innocence in the botched carjacking and shooting death that landed him a life sentence without the possibility of parole. He claims the two robbery victims falsely fingered him in photo lineups after police tracked him down based on his tight childhood bond with Batiste.

Toca was barely 17 when his buddy was killed and a young New Orleans police officer named Marlon Defillo, who knew the young pair, pointed detectives toward Toca.

His lawyers have presented numerous statements from friends and family members of Batiste who say Toca had left Batiste and others at a dance at the Superdome hours before the botched robbery and shooting in order to have sex with a girl at a Mid-City motel.

Since Toca’s trial, witnesses have pointed to another friend, Edison Learson, as the actual shooter, claiming Learson confessed it to them.

Learson, who has since amassed a lengthy criminal record in California, was in San Quentin State Prison when Toca’s case came before an Orleans Parish judge in 2010 for a post-conviction hearing. He sent word in a letter that he would stay silent if called to testify.

Toca’s hopes for a new trial in state court had been on hold before Thursday’s deal.

“The district attorney believes that this individual was guilty of the crimes of which he was convicted today,” Bowman said on Thursday.

Toca’s attorneys, however, declared him “innocent of the crime for which he was convicted and those to which he pled guilty today.”

“Innocence Project New Orleans has been working on the case for years and in communication with the district attorney for years. This week the district attorney made a firm offer which would see Mr. Toca immediately released from his life sentence,” Toca’s attorneys said in a statement,

“Mr. Toca has already served 31 years wrongly imprisoned. It is understandable and appropriate that he chose certain release from Angola prison over the uncertainty of continuing his legal fight.”

Joyce Dolliole, Batiste’s 76-year-old aunt, said Toca wept as he signed the plea agreement.

“He just was a little sad he had to sign the paper. We all started to cry, because he had to say he killed his best friend when he didn’t want to do it,” Dolliole said. “We know, God knows and he know that he’s not guilty,” she added. “My work is done, as a family member of the deceased fighting for him to be free.”

She said Toca plans to visit Batiste’s grave with family members after his release.

“We felt my nephew’s spirit in the courthouse,” she said. “Eric would not have wanted him to do no time for something he didn’t do.”

Prosecutors at Toca’s trial alleged that he and Batiste were in on the robbery together, and that Toca accidentally shot Batiste in the middle of a scuffle with one of the alleged victims over the car keys.

He “just sort of backed up a few steps, as if he could not believe what he had done,” one of the targets of the armed robbery said of the shooter.

Bowman, the DA’s spokesman, said prosecutors reached out to the victims, who were “steadfast in their identification” of Toca as the gunman. Nevertheless, “at least one of them felt the time (Toca) had spent in prison was sufficient,” Bowman said.

Bowman insisted that the DA’s decision to come to a deal on Toca’s release was unrelated to the pending U.S. Supreme Court case, in which Cannizzaro’s office had been gearing up to argue against the retroactive application of Miller v. Alabama.

The high court didn’t ban states from sentencing some young killers to life without parole. But the 5-4 majority opinion insisted that courts must first weigh a defendant’s youth, adding that “we think appropriate occasions for sentencing juveniles to this harshest possible penalty will be uncommon.” The court said “youth matters for purposes of meting out the law’s most serious punishments,” citing “children’s diminished culpability and heightened capacity for change” when compared with adults.

In legal filings, Cannizzaro’s office argued that it would be a fool’s errand to force local judges, years or decades later, to discern a long-ago juvenile’s capacity for change.

Advocates for juvenile lifers argued that the task would be made easier because judges can review an inmate’s record while behind bars. And they saw Toca’s case as a promising bellwether for what the high court justices might do.

A former high school dropout, Toca earned a college degree behind bars with above-average marks, along with a bachelor’s degree in Christian ministry from New Orleans Baptist Theological Seminary. He also has a diploma from an intensive carpentry program.

His record behind bars shows occasional disciplinary problems, though recent years have seen just a handful of small-time infractions.

According to the state, 272 Louisiana inmates had been sentenced as juveniles to life without the possibility of parole as of April 2013 — the bulk of them, like Toca, having been sentenced before the U.S. Supreme Court decision.

State Supreme Courts in Pennsylvania, Michigan and Minnesota also have found that Miller v. Alabama does not apply retroactively, setting up the fight at the U.S. Supreme Court.

Toca’s vacated conviction and release will leave the issue unresolved for now, said Cara Drinan, an associate professor of law at Catholic University of America. Still, she expects the Supreme Court to take up the retroactivity question relatively soon in some other case, now that it has signaled its interest in settling the issue.

“For George Toca, this is a victory and a great thing,” Drinan said. “For those of us looking at the bigger issue, and for the hundreds of people waiting for a resolution, we’ll have to wait.”

The deal in the Toca case follows Cannizzaro’s blockbuster decision last May, also in a deal with Innocence ProjectNO attorneys, to free convicted murder Reginald Adams after 34 years.

Unlike the Toca case, the reversal in Adams’ case involved what Cannizzaro found to be “manifest intentional prosecutorial misconduct.” In that case, Cannizzaro suggested that police and prosecutors conspired to railroad Adams by hiding evidence of another suspect and a recovered murder weapon.

Cannizzaro agreed to drop Adams’ conviction outright. The case helped spark an announcement in August of a new partnership between the DA’s office and Innocencet Project New Orleans to jointly review old cases for bad convictions. The new “Conviction Integrity Project” is believed to be the first of its kind in the country teaming prosecutors and advocates.

Discussions between IPNO and the DA on Toca’s case predate that agreement.

In an unrelated case last week, Cannizzaro’s office agreed to let Leonard Johnson plead guilty to manslaughter and go free after 38 years in prison on a murder conviction that U.S. District Judge Helen “Ginger” Berrigan overturned in a recent order granting him a new trial.

In that case, Johnson admitted shooting Ira Bodere and Richard McClarity during an argument at a New Orleans swimming pool in 1974, killing McClarity, but he said he fired in the heat of the moment to defend his brother.

He fought his conviction for decades, turning up a conflicting account from Bodere in a police report, and also claiming an unconstitutional jury instruction, in a case that languished in District Judge Frank Marullo’s courtroom before Berrigan ordered that Johnson be retried or released.

In that case, Cannizzaro’s office may have been hard pressed to successfully prosecute the case again.

While Adams is now seeking $330,000 in state compensation for his misspent time at Angola, Toca’s plea makes it unlikely that he would succeed with a similar claim.

Under the order that Williams signed Thursday, Toca agreed to a 21-year sentence on the manslaughter count and a consecutive sentence of 40 years total for both armed robbery counts. His release comes after serving half of those 61 years.

Follow John Simerman on Twitter, @johnsimerman.