ST. LOUIS — A Harvard Law School professor whose past clients include the family of the 18-year-old fatally shot in 2014 by a policeman in Ferguson, Missouri, has joined the prosecution team in the criminal case against Missouri Gov. Eric Greitens.

The St. Louis Post-Dispatch reports that Circuit Judge Rex Burlison on Monday approved Circuit Attorney Kim Gardner's motion to have Ronald S. Sullivan join the prosecution.

Greitens was indicted in February on felony invasion of privacy. He is accused of taking a compromising photo of a woman with whom he was having an affair without her permission in 2015, before he was elected.

Greitens has denied criminal wrongdoing.

Sullivan was the attorney for the family of Michael Brown, whose death set off months of protests in and around the St. Louis suburb.