(STMW) — A former Illinois state trooper was convicted of murder Thursday for fatally shooting his girlfriend at a graduation party in 2012.

A jury found 34-year-old Brian Himber guilty of first-degree murder for shooting and killing 29-year-old Tracy Mays in west suburban Westchester in July 2012, according to the Cook County state’s attorney’s office. He faces 45 years to life in prison for the crime.

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Mays was sitting on a porch a few hours after she and Himber arrived at a graduation party when the off-duty trooper shot her multiple times with a .380 caliber gun, prosecutors said. He then shot himself once in the chin; he was off-duty at the time of the shooting, prosecutors say.

Mays was taken to an area hospital where she later died, prosecutors said.

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Himber will be held in Cook County Jail until his sentencing hearing on March 4, the state’s attorney’s office said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2016. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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