WASHINGTON (AP) — The union representing Metro transit police is suing the transit agency to reinstate an officer who the union says was wrongly fired.

The Washington Post reports Sherman Benton, a Metro police officer, was fired in April 2011 after an incident with a woman in Atlantic City, N.J., while he was off duty.

Court documents say the two were involved in a physical altercation. Benton was taken into custody by police and charged with injuring his girlfriend. The charges were later dropped.

The union’s lawsuit says Benton returned to work. Metro conducted an investigation and found Benton lied when recounting what happened. He was fired, but the firing was overturned by an arbitrator.

Later, a Maryland commission declined to recertify Benton as an officer, and Metro refused to reinstate him.

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