Cal. Pub. Util. Code § 120506
The obligation of the board to meet and confer in good faith with the duly certified labor organization and to agree on the terms of a written collective-bargaining agreement with such labor organization covering the wages, hours, working conditions, and benefits of the employees represented by such labor organization in the appropriate unit, and to comply with the terms thereof, shall not be limited or restricted by the provisions of the Government Code or other laws or statutes. The obligations of the board to bargain collectively shall extend to all subjects of collective bargaining which are, or may be, mandatory subjects of collective bargaining with a private employer, including retroactive provisions and benefits for retired employees.
Ca. Pub. Util. Code § 120506