California Business And Professions Code Section 7583.12

(a) No employee of a licensee shall carry or use a firearm unless the employee has in his or her possession both of the following: (1) A valid guard registration card issued pursuant to this chapter. (2) A valid firearm qualification card issued pursuant to this chapter. (b) Paragraph (2) of subdivision (a) shall not apply to a duly appointed peace officer, as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2 of the Penal Code, who meets all of the following: (1) He or she has successfully completed a course of study in the use of firearms. (2) He or she is authorized to carry a concealed firearm in the course and scope of his or her employment pursuant to subdivision (a) of Section 12027 of the Penal Code. (3) He or she has proof that he or she has applied to the bureau for a firearms qualification card. (c) (1) This section shall not apply to a duly appointed peace officer, as defined in Chapter 4.5 (commencing with Section 830) of Title 3 of Part 2 of the Penal Code, who has written approval from his or her primary employer, as defined in paragraph (2) of subdivision (i) of Section 7583.9, to carry a firearm while working as a security guard or security officer. (2) A peace officer exempt under this subdivision shall carry on his or her person a letter of approval from his or her primary employer authorizing him or her to carry a firearm while working as a security guard or security officer.