A Jefferson Parish jury Wednesday convicted Carey Garrison of manslaughter in the 2011 shooting death of Anthony Williams in Marrero, rejecting the idea that he acted purely in self-defense but not going as far as the second-degree murder verdict sought by prosecutors.

The verdict means Garrison, 20, will be sentenced to up to 40 years in prison. A second-degree murder conviction would have carried a mandatory life sentence.

Garrison will find out how long he’ll spend in prison when he is sentenced on Oct. 14.

The shooting took place on Buccola Avenue just after a Martin Luther King Day parade on Jan. 17, 2011.

Garrison, then 17, told investigators he had heard that Williams, known as “Fat Tony” and said to be part of a gang called the Shire Boys, meant to kill him.

When Williams cornered him at the end of the dead-end street where Garrison lived, the two scuffled. Garrison grabbed Williams’ gun from his waist and shot him several times.

Garrison said he remembered firing only the first shot and then “blacked out,” but prosecutors told jurors during the three-day trial that the additional bullets fired into Williams’ body while he fell and lay bleeding on the street were the acts of a cold-blooded killer.

Garrison was led out of the courtroom in handcuffs Wednesday. The jury deliberated for just over two hours.

In closing arguments, prosecutors attempted to cast doubt on Garrison’s version of events.

Prosecutor Seth Shute said Garrison and Williams were the only two people who could explain why the shooting occurred, and that with Williams dead, Garrison was “feeding you stuff to get him off the hook.”

“Who told us that Tony was coming to hurt him? Only Carey Garrison,” Shute said.

Defense attorney Andrew Duffy, however, painted the investigation as one that had zeroed in on Garrison from the start and had no interest in figuring out why Williams went to Garrison’s street after the parade armed with a gun.

He said that if Garrison hadn’t acted as he did, seizing the gun, he would have been shot and Williams would have been on trial.

Duffy said Garrison made a split-second decision that saved his life, rooted in the survival instinct of fight-or-flight.

But prosecutors said photos of Williams’ bullet-riddled body and testimony from ballistics experts tell a different tale, with gunshot wounds under Williams’ arm and his head showing how Garrison stood over him and shot him several more times.

Prosecutor Josh Vanderhooft noted that one of the bullets entered Williams’ buttocks and exited through his clavicle, suggesting he was bent over and facing away from Garrison at that moment.

Prosecutors cited the convenience of Garrison’s memory loss — that he “blacked out” during the period in which he fired several more times while Williams fell and after he hit the ground.

In the end, the jury split the difference between what the two sides requested, convicting Garrison of manslaughter — a charge that he himself was said to have suggested.

Matthew Vazquez, lead investigator with the Jefferson Parish Sheriff’s Office, testified Tuesday that during an unrecorded portion of his interview, Garrison asked if he could just admit to manslaughter and get it over with.