ANNAPOLIS, Md. (WJZ) — A leader of the white supremacist Aryan Brotherhood gang in the Maryland Correctional Institution in Jessup was sentenced to life without parole for ordering the murder of a member of a rival gang, Anne Arundel County State’s Attorney Anne Colt Leitess said Tuesday.

Joseph Leissler, 52, was convicted in August of first-degree murder, three gang-related charges and conspiracy to commit first-degree murder after he ordered three gang members to attack John O’Sullivan, a member of the gang Dead Man Incorporated, with homemade prison knives.

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The Aug. 14, 2016 attack was apparently carried out as retaliation for a gang-related assault at a different prison, prosecutors said.

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In 2020, Vincent Bunner, Calvin Lockner, two of the underlings who attacked O’Sullivan, were convicted of second-degree murder.

A third associate, Brian Hare, pleaded guilty to first-degree murder and testified against his co-defendants, prosecutors said.

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“The defendant has been leading a violent life inside the jail and this sentence sends a clear message that justice doesn’t stop at the prison door and that any violent acts committed within prison will have real world consequences,” Leitess said. “It’s my hope that the verdict provides the loved ones of Mr. O’Sullivan with a sense of solace, now that the fourth person involved in his death was held accountable and sentenced.”

CBS Baltimore Staff