A St. Louis police officer has sued the city over the way he was treated while he was undercover during protests against police brutality.

Luther Hall was beaten by fellow police officers during a mass arrest of protesters in September 2017. He suffered serious injuries and has not returned to work.

The federal lawsuit filed Monday says the officers used excessive force during the arrest and treated Hall differently because he was black.

Hall also accuses Mayor Lyda Krewson, the police department, the officers who beat him and other city officials of trying to cover up the civil rights violations. One of the officers involved, he said, was later promoted, “showing that this misconduct is not only protected but rewarded by the City and Department.”

Hall is seeking unspecified damages for the assault and the civil rights violations. The city did not immediately have a comment on his suit.

Bailey Colletta, one of the officers named in the lawsuit, has already pleaded guilty in a separate criminal case. Three others are set to go on trial in December.

Hall himself has faced federal lawsuits accusing him of violating the civil rights of individuals he arrested. Two cases — one filed in 1999 and another in 2003 — were dismissed. The city settled a third in 2010 for $865,000.

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