NATCHEZ — Keldrick Washington will be joining in jail his co-defendant in the May 2011 Natchez City Cemetery shooting death of a Natchez teenager. Washington pleaded guilty to manslaughter late Monday afternoon.

Washington, 20, was set to go to trial Tuesday for the murder of 18-year-old Quinton Brown, but entered his plea Monday during the 4 p.m. hour. He had until 5 p.m. to do so.

Washington was sentenced by Judge Forrest “Al” Johnson to 15 years prison, though he will only be required to serve five of those years. The remainder of the sentence will be served on post-release probation, with five of those years supervised and five of them unsupervised.

Washington’s manslaughter plea is connected with the concept of “culpable negligence,” District Attorney Ronnie Harper said.

Culpable negligence is the idea that given knowledge of the situation, the defendant should have reasonably deduced that something bad would happen but continued to participate in it anyway.

Washington’s co-defendant, Adrian Williams, 22, was tried separately, convicted and sentenced to life in prison without chance of release until age 65 Nov. 15.

Harper said Tuesday he felt the plea and sentencing were a reasonable and just conclusion to the case based on what the prosecution believed to be Washington’s participation in the killing.

“It was never our understanding nor did we have any evidence that he was a shooter,” Harper said. “(Washington’s participation) was more in line with being an accessory. There were some concerns we had about being able to prove what knowledge he had that the defendant Williams was going to kill Brown.”

The prosecution believed that Washington knew Williams had a grudge against the victim, Harper said, and despite that knowledge Washington asked Brown to get in a vehicle with them to go to the cemetery, where the killing occurred.

“(Washington) obviously had some knowledge of the circumstances as far as being armed and that (Washington) had some problems with (Brown) and some intentions to ‘get him,’” Harper said. “We had some problems being able to prove what his knowledge of ‘get him’ was.”

A third man, Denzel Fort, pleaded guilty to the charge of accessory after the fact in March and later testified in Williams’ trial. Fort has not yet been sentenced.

Brown was found shot to death with multiple gunshot wounds, including to his back and head. In testimony that Fort gave at Williams’ trial, he stated that the four men had gone to the cemetery to test out pistols they had acquired. Fort testified that while he had taken a gun to the cemetery, he did not go in with the other men and that after he heard a series of gunshots Washington and then Williams exited the cemetery without Brown.

Fort testified that Williams said Brown was dead and threatened Fort and Washington that if they told anyone what had happened he would kill them.

Fort and Williams later went to the Natchez Police Department to give unsolicited statements about the events. Though Williams gave three statements to police, his final statement was that he was the only shooter in the killing.

Williams’ final statement alleged that Brown pulled a gun before Williams shot him.

Williams later told police where to find the weapons investigators believed were used in the killing in exchange for a cigarette.

Harper said the prosecution at all times believed Williams to be the actual killer of Brown.