Existing federal law establishes the militia of the United States, specifies who is eligible to be a part of the militia, divides the militia into the organized and unorganized militia, and defines the organized militia as the National Guard and the Naval Militia. Existing federal law authorizes the President of the United States to call units of the National Guard of any state into federal service if certain criteria are met. Existing federal law, the Emergency Management Assistance Compact, authorizes member states to provide for mutual assistance between the states in managing a disaster that is declared by the governor of the affected state.

Existing law establishes within state government a Military Department that includes, among other things, the office of the Adjutant General, the California National Guard, and the State Guard. Under existing law, the militia of the state is comprised of the California National Guard, the State Guard, the Naval Militia, and the unorganized militia. Existing law makes the Governor, by virtue of holding their office, the commander in chief of the militia of the state.

The California Constitution requires the state to reimburse local agencies and school districts for certain costs mandated by the state. Statutory provisions establish procedures for making that reimbursement.