Cal. Labor Code § 148.2

The appeals board may employ necessary assistants, officers, experts, hearing officers, and such other employees as it deems necessary. All such personnel of the appeals board shall be under the supervision of the chairman of the appeals board or an executive officer to whom the chairman delegates such responsibility. All such personnel shall be appointed pursuant to the State Civil Service Act (Part 2 (commencing with Section 18500) of Division 5 of Title 2 of the Government Code), except for the one exempt deputy or employee allowed by subdivision (e) of Section 4 of Article XXIV of the California Constitution. The salaries of the hearing officers shall be fixed by the State Personnel Board at a rate comparable to that of other referees or hearing officers in state service whose duties and responsibilities are comparable, without regard to whether such other positions have membership in the State Bar of California as a prerequisite to appointment.