A former Louisiana police officer has been sentenced to 18 months in prison for repeatedly punching a man who had his hands up in surrender.

U.S. Attorney David Joseph says Robert Hammac, 44, of Lucedale, Mississippi, was sentenced Tuesday for depriving the man of his rights by using excessive force.

says the man identified only as G.T. was not resisting or posing a threat.

At the time, Hammac was a Lake Charles police officer. He pleaded guilty in August.

According to court documents, Hammac and other officers chased G.T.’s car for several miles on May 8, 2017. After stopping, he raised his hands. Other officers began pulling him out of the car. Hammac pulled him back in from the passenger’s side, then repeatedly punched his head.