COLUMBIA (AP) – The city of Columbia and Boone County have been dropped as defendants in a $100 million federal civil rights lawsuit filed on behalf of a man with a vacated murder conviction.

The Columbia Daily Tribune reports that U.S. District Judge Nanette Laughrey on Friday granted a motion by Ryan Ferguson’s attorney to voluntarily dismiss the city and county. A former Columbia police chief and sergeant and two investigators for the county prosecutor’s office were also removed.

Former Boone County prosecutor Kevin Crane, now a circuit judge, had previously been dismissed from the suit. Six current or former Columbia police officers remain as defendants.

Ferguson was convicted in 2005 of killing Columbia Daily Tribune sports editor Kent Heitholt, but his conviction was vacated last year.