Rondell "Ron" Pierce is an officer with the Los AngelesPolice Department. He is assigned to the Hollywood Division. He is initially partnered with George Irving in patrol. He is later promoted to detective and partnered with Santiago Robertson. Pierce is part of the Howard Elias murder task force. He focuses on the murder of the Angels Flight train operator and his persistence eventually leads to him finding a key piece of physical evidence - the bullet.
Robertson transfers to Newton Division and Pierce works solo for several months. He supports Bosch and Edgar with the Farmacia Esquivel shooting investigation. He works the outside of the scene and using a canine unit tracks the shooters escape to a nearby parking garage. Later he links a missing persons report to the case - Charles Fagan. Lieutenant Grace Billets assigns incoming Detective Christina Vega as Pierce's new partner.