PITTSBURGH — A federal court jury convicted a police officer of violating a man’s civil rights by using a stun gun on him three times while he was handcuffed.

Wednesday’s felony conviction of suspended Millvale Officer Nicole Murphy effectively means she’ll never work as a police officer again, barring a successful appeal. It also means she’ll likely face up to three years in prison when she’s sentenced March 13, according to defense attorney Robert Stewart.

“Law enforcement officers are sworn to uphold and obey the law,” U.S. Attorney David Hickton said after the verdict, “Nicole Murphy did neither when she used a dangerous weapon to subdue a handcuffed defendant, thereby violating his civil rights.”

Murphy acknowledged using the device on Thomas Jason James Smith after his arrest for public drunkenness in September 2012.

But Stewart argued the 30-year-old Murphy was justified because she was trying to stop Smith from banging his head on a desk and office cubicle. However, Murphy had said in official police reports Smith was combative and spat on her partner, which that officer has denied.

“I think the mere fact that she used a Taser on someone in handcuffs was enough for that jury,” Stewart said. A defense expert on the police use of force had testified Murphy was justified in using the stun gun to control the situation, even though Smith was in handcuffs.

Stewart called Murphy’s partner, former officer Casey Bonincontro, a “liar” and said Bonincontro “sat there like a bump on a log” laughing and doing nothing to intervene as Smith sat handcuffed on the floor of the police station, spouting gibberish and banging his head.

Bonincontro testified Smith hadn’t spat on, attacked or otherwise threatened him, though Murphy used that as justification for stunning Smith. Stewart contends other witnesses showed Bonincontro got several details wrong.

“I don’t know what they felt was so compelling,” Stewart said of the jury, “especially the primary witness.”

Bonincontro became the key witness because he recorded 52 seconds of the encounter, including Murphy zapping Smith a final time with the Taser. Although she expressed concern about Smith banging his head, Murphy also called him a “retard” before stunning him.

Bonincontro shared the video with his chief and another officer who had a beef with Murphy, who had sided against the other officer in a disciplinary matter. That officer leaked the video to Pittsburgh-area media outlets in early 2013, prompting the FBI investigation that led to Murphy being indicted.

The charge she faced, deprivation of rights under color of law, carries a maximum 10-year sentence. Stewart said federal sentencing guidelines, which take into account the crime as well as Murphy’s lack of a criminal record, suggest she’ll face two to three years in prison.