PIKESVILLE, Md. (WJZ) — Maryland State Police’s Homicide Unit was commended Wednesday for the five-year criminal investigation that resulted in the conviction of 52-year-old Joseph Leissler. According to authorities, Leissler ordered the death of another inmate in 2016.

Leissler is an inmate at Jessup Correctional Institution. He was found guilty of first and second-degree murder, conspiracy to commit first-degree murder, gang participation by causing the death of another inmate and supervising a gang.

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“The hard work, dedication and persistence demonstrated by investigators of the Maryland State Police Homicide Unit went beyond the initial murder investigation and were key in securing a conviction of the individual responsible for ordering the death of an inmate,” said Colonel Woodrow W. Jones III, Superintendent of the Maryland State Police.

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Officials said the initial investigation began in Aug. 2016 following the murder of 43-year-old John O’Sullivan. Officials said O’Sullivan was stabbed to death during an unprovoked attack while leaving the showers. He was a member of a rival gang, Dead Man Inc.

After a thorough investigation, three suspects were revealed and were later charged in 2016. They were identified as Brian Hare, Vincent Bunner and Calvin Lochner and were all found to be members of the Aryan Brotherhood. They were convicted in 2020.

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Officials said information revealed the 2016 murder was ordered by the leader of Aryan Brotherhood, who was later identified as Leissler.

CBS Baltimore Staff