Cal. Gov. Code § 12701
As soon as practicable after the effective date of this chapter, and thereafter as soon as practicable after election and qualification to office, each of the constitutional officers named in Section 12700 shall appoint and designate by filing with the Secretary of State the names of at least three and not more than seven citizens qualified to become candidates to the office as their respective successors in the event that such officer is unavailable as a result of disaster. Any such appointee may be replaced by the appointing officer at any time and for any reason. The appointees of the Attorney General may include persons holding the Office of Assistant Attorney General. The appointees of the Controller, Secretary of State, and Treasurer may include persons holding office as their deputies or assistants.
In making appointments each constitutional officer shall give consideration to the places of residence and employment of the officer's appointees and shall appoint from different parts of the state so that for each office for which appointments are made there shall be the greatest probability of survival in the event of a disaster of some or all of the appointees.
The names of the persons designated pursuant to this section shall be submitted to, and be subject to confirmation by, the Senate as soon as possible after that designation is made.
Each person appointed as provided in this section shall take the oath of office and shall deliver to the Secretary of State within 30 days after appointment a written declaration under oath that the appointee accepts the appointment and will faithfully perform the obligations imposed upon the appointee thereby.
Ca. Gov. Code § 12701