BALTIMORE — Prosecutors say two Baltimore police sergeants are prepared to testify against an officer charged with shooting an unarmed man to death last year outside a Mount Vernon nightclub.

Officer Gahiji Tshamba is charged with first-degree murder in the 2010 slaying of 32-year-old Tyrone Brown. Police say Tshamba fired 13 shots at Brown from his police department handgun, hitting Brown 12 times.

Prosecutors say the sergeants will testify that Tshamba appeared to be under the influence of alcohol.

Tshamba’s attorneys don’t dispute that their client shot Brown, but say he was acting in his role as a police officer. They say Tshamba intervened when he saw Brown grope a woman and the situation escalated.

The bench trial is set to begin Wednesday in Baltimore Circuit Court.