The Office of the County Counsel was created in August 1969. It is a public law office engaged in a diverse civil practice. Prior to the creation of the office, Contra Costa County was the most populous county in California still having its civil legal work done by the District Attorney. The first County Counsel was John B. Clausen, who served from 1969 to 1984. He was succeeded by Victor J. Westman (1984 to 2001), Silvano B. Marchesi (2001 to 2009), Sharon L. Anderson (2009 to 2021), Mary Ann McNett Mason (2021 to 2022), and Thomas L. Geiger (2023-Present).