California Code, Government Code - GOV § 19844

(a) The department shall provide the extent to which, and establish the method by which, ordered overtime or overtime in times of critical emergency is compensated.  The department may provide for cash compensation at a rate not to exceed 1 1/2 times the regular rate of pay, and the rate may vary within a class depending upon the conditions of work, or the department may provide for compensating time off at a rate not to exceed 1 1/2 hours of time off for each hour of overtime worked.  The provisions made under this section shall be based on the practices of private industry and other public employment, the needs of state service, and internal relationships.

(b) If the provisions of this section are in conflict with the provisions of a memorandum of understanding reached pursuant to Section 3517.5, the memorandum of understanding shall be controlling without further legislative action, except that if such provisions of a memorandum of understanding require the expenditure of funds, the provisions shall not become effective unless approved by the Legislature in the annual Budget Act.