(CNN) A former Tallassee police investigator pleaded guilty to assaulting a handcuffed 24-year-old man after his arrest.

According to the guilty plea, Brandon Smirnoff, 27, was on duty in pursuit of the victim on a four-wheeler. Several officers had placed the man in handcuffs and before placing him into his vehicle, Smirnoff lifted him in the air and repeatedly slammed him to the ground.

When putting him into the car, Smirnoff reportedly slammed the man's head into the side of the vehicle, the statement said.

Smirnoff's attorney, Richard White, told CNN "I think he's sorry for what he did and I think that's a sign by him pleading. He has come to the understanding that what he did was wrong."

White said the government gave them a fair offer and after talking to his family and praying about it, Smirnoff came to the decision to plead guilty -- which he says what not an easy decision.

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