PEN §830.39: (a) Any regularly employed law enforcement officer of the Oregon State Police, the Nevada Department of Motor Vehicles and Public Safety, or the Arizona Department of Public Safety is a peace officer

(a) Any regularly employed law enforcement officer of the Oregon State Police, the Nevada Department of Motor Vehicles and Public Safety, or the Arizona Department of Public Safety is a peace officer in this state if all of the following conditions are met: (1) The officer is providing, or attempting to provide, law enforcement services within this state on the state or county highways and areas immediately adjacent thereto, within a distance of up to 50 statute miles of the contiguous border of this state and the state employing the officer. (2) The officer is providing, or attempting to provide, law enforcement services pursuant to either of the following: (A) In response to a request for services initiated by a member of the California Highway Patrol. (B) In response to a reasonable belief that emergency law enforcement services are necessary for the preservation of life, and a request for services by a member of the Department of the California Highway Patrol is impractical to obtain under the circumstances. In those situations, the officer shall obtain authorization as soon as practical. (3) The officer is providing, or attempting to provide, law enforcement services for the purpose of assisting a member of the California Highway Patrol to provide emergency service in response to misdemeanor or felony criminal activity, pursuant to the authority of a peace officer as provided in subdivision (a) of Section 830.2, or, in the event of highway-related traffic accidents, emergency incidents or other similar public safety problems, whether or not a member of the California Highway Patrol is present at the scene of the event. Nothing in this section shall be construed to confer upon the officer the authority to enforce traffic or motor vehicle infractions. (4) An agreement pursuant to Section 2403.5 of the Vehicle Code is in effect between the Department of the California Highway Patrol and the agency of the adjoining state employing the officer, the officer acts in accordance with that agreement, and the agreement specifies that the officer and employing agency of the adjoining state shall be subject to the same civil immunities and liabilities as a peace officer and his or her employing agency in this state. (5) The officer receives no separate compensation from this state for providing law enforcement services within this state. (6) The adjoining state employing the officer confers similar rights and authority upon a member of the California Highway Patrol who renders assistance within that state. (b) Whenever, pursuant to Nevada law, a Nevada correctional officer is working or supervising Nevada inmates who are performing conservation-related projects or fire suppression duties within California, the correctional officer may maintain custody of the inmates in California, and retake any inmate who should escape in California, to the same extent as if the correctional officer were a peace officer in this state and the inmate had been committed to his or her custody in proceedings under California law. (c) Notwithstanding any other provision of law, any person who is acting as a peace officer in this state in the manner described in this section shall be deemed to have met the requirements of Section 1031 of the Government Code and the selection and training standards of the Commission on Peace Officer Standards and Training if the officer has completed the basic training required for peace officers in his or her state. (d) In no case shall a peace officer of an adjoining state be authorized to provide services within a California jurisdiction during any period in which the regular law enforcement agency of the jurisdiction is involved in a labor dispute.