Cal. MVC § 365

When an armed force is called out for the purpose of suppressing an unlawful or riotous assembly, or arresting the offenders, or in any emergency or under the provisions of Sections 128, 143, or 146 of this code, and is placed under the temporary direction of any civil officer, it shall obey the orders of such civil officer which extend only to the direction of the general or specific object to be accomplished. The tactical direction of the troops, the kind and extent of force to be used, and the particular means to be employed to accomplish the object specified by the civil officer are left solely to the commanding officer of the active militia on duty or to the commanding officer of the unorganized militia called to the service of the State.