LOS ANGELES (CBSLA.com) — A jury deliberated for less than three hours before deciding that a L.A. man was sane when he boarded a Metro bus and fatally shot the driver in West Hollywood three years ago, according to a prosecutor.

Anthony Craig Chambers, 44, had already been convicted of first-degree murder by another jury in March for the shooting death of Alan Thomas, Deputy District Attorney Marna Miller said. They found true a special circumstance allegation of murder of a bus driver in the performance of his duties. The panel deadlocked however on whether Chambers was sane at the time of the crime.

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On May 20, 2012, Chambers got on a bus and, moments later, pulled a shotgun out of a suitcase and shot the 51-year-old driver twice without provocation, according to the prosecutor.

Police arrested Chambers after he tried climbing out of a bus window on Santa Monica Boulevard, west of La Cienega Boulevard.

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Chambers is facing life in prison without the possibility of parole. He is due back in court on March 4 for sentencing.

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