(a) The voters of the 119th Judicial District elect a district attorney who represents the state in all criminal and habeas corpus cases in that district court.
(b) The district attorney of the 119th Judicial District may request the district attorney of the 51st Judicial District to assist in the trial of a criminal or habeas corpus case before the 119th District Court. The district attorney of the 119th Judicial District has absolute control and management of those cases.