Cal. LAB § 3366

(a) For the purposes of this division, each person engaged in the performance of active law enforcement service as part of the posse comitatus or power of the county, and each person (other than an independent contractor or an employee of an independent contractor) engaged in assisting any peace officer in active law enforcement service at the request of such peace officer, is deemed to be an employee of the public entity that he or she is serving or assisting in the enforcement of the law, and is entitled to receive compensation from the public entity in accordance with the provisions of this division.

(b) Nothing in this section shall be construed to provide workers’ compensation benefits to a person who is any of the following:

(1) A law enforcement officer who is regularly employed by a local or state law enforcement agency in an adjoining state and who is deputized to work under the supervision of a California peace officer pursuant to paragraph (4) of subdivision (a) of Section 832.6 of the Penal Code.

(2) A law enforcement officer who is regularly employed by the Oregon State Police, the Nevada Department of Motor Vehicles and Public Safety, or the Arizona Department of Public Safety and who is acting as a peace officer in this state pursuant to subdivision (a) of Section 830.32 of the Penal Code.