California Code, Penal Code – PEN § 13701
(b) The written policies shall encourage the arrest of domestic violence offenders if there is probable cause that an offense has been committed.  These policies also shall require the arrest of an offender, absent exigent circumstances, if there is probable cause that a protective order issued under Chapter 4 (commencing with Section 2040 ) of Part 1 of Division 6, Division 10 (commencing with Section 6200 ), or Chapter 6 (commencing with Section 7700 ) of Part 3 of Division 12, of the Family Code, or Section 136.2 of this code, or by a court of any other state, a commonwealth, territory, or insular possession subject to the jurisdiction of the United States, a military tribunal, or a tribe has been violated.