The commission may employ officers, assistants, experts, and other employees it deems necessary. All personnel of the commission shall be under the supervision of the chair or an executive officer to whom he or she delegates this responsibility. All 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 exemption allowed by subdivision (e) of Section 4 of Article VII of the California Constitution.