NEW YORK (CBSNewYork/AP) — A disciplinary trial began Tuesday for the NYPD officer who shot and killed an unarmed teenager in the Bronx in 2012.

Officer Richard Haste appeared Tuesday at an administrative court on departmental charges accusing him of failing to use proper tactics in the killing of 18-year-old Ramarley Graham.

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Authorities have said police first encountered Graham when they spotted him and two other people walking into a Bronx bodega on the afternoon of Feb. 2, 2012 and then immediately walking out.

The officers, who were conducting a street narcotics investigation, said they saw Graham adjusting his waistband and told fellow officers they believed he had a gun.

Police followed him to his Bronx home where Haste forced his way into a bathroom and shot Graham once.

Haste was originally charged with manslaughter but he was never prosecuted. He’s has been on modified duty since the shooting, but Graham’s family says the officer should lose his job.

“My purpose is to make sure Richard Haste is fired,” mother Constance Malcolm said Tuesday.

Haste’s attorney says Graham never showed his hands as he was instructed to do before the shooting.

“Officer Haste, although he knows he committed no misconduct, is remorseful for the loss of a life,” defense attorney Stuart London said.

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In Tuesday’s proceedings, London pointed out the NYPD Firearm Discharge Review Board ruled the shooting itself justified, but that he did not use proper tactics.

“If the shooting is justified, the tactics should be justified and in this case they’re looking for a scapegoat because of the unfortunate outcome of this shooting,” he said.

In opening statements, NYPD lawyer Beth Douglas said Haste used poor judgment by forcing his way into a Bronx apartment and firing on Graham. Other officers had reported the 18-year-old had a gun, but no weapon was found.

Outside police headquarters, protesters held signs demanding Haste be fired. Malcolm says she deserves justice for her son.

“Ramarley committed no crime,” she said. “Ramarley didn’t run from anybody. He didn’t point a gun at anybody. So why is my son not here?”

In March of last year, federal prosecutors declined to file civil rights charges against the officer.

The departmental trial is expected to last through the end of the week. As CBS2’s Andrea Gryme’s reported, the NYPD deputy commissioner of trials will then issue a recommendation to the police commissioner, who has the final say on whether or not Haste will be fired.

London says he expects a decision in the next 60-90 days.

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