PEN §831: (a) A custodial officer is a public officer, not a peace officer, employed by a law enforcement agency of a city or county who has the authority and responsibility for maintaining custody of prisoners

(a) A custodial officer is a public officer, not a peace officer, employed by a law enforcement agency of a city or county who has the authority and responsibility for maintaining custody of prisoners and performs tasks related to the operation of a local detention facility used for the detention of persons usually pending arraignment or upon court order either for their own safekeeping or for the specific purpose of serving a sentence in that facility. (b) A custodial officer shall not carry or possess firearms in the performance of his or her official duties. A custodial officer may use a firearm that is a less lethal weapon, as defined in Section 16780, in the performance of his or her official duties, at the discretion of the employing sheriff or chief of police, as applicable, or his or her designee. A custodial officer who uses a less lethal weapon shall be trained in its use and shall comply with the policy on the use of less lethal weapons as set forth by the sheriff or chief of police. (c) Each person described in this section as a custodial officer shall, within 90 days following the date of the initial assignment to the position, satisfactorily complete the training course specified in Section 832. In addition, each person designated as a custodial officer shall, within one year following the date of the initial assignment as a custodial officer, have satisfactorily met the minimum selection and training standards prescribed by the Board of State and Community Corrections pursuant to Section 6035. Persons designated as custodial officers, before the expiration of the 90-day and one-year periods described in this subdivision, who have not yet completed the required training, may perform the duties of a custodial officer only while under the direct supervision of a peace officer as described in Section 830.1, who has completed the training prescribed by the Commission on Peace Officer Standards and Training, or a custodial officer who has completed the training required by this section. (d) At any time 20 or more custodial officers are on duty, there shall be at least one peace officer, as described in Section 830.1, on duty at the same time to supervise the performance of the custodial officers. (e) This section does not confer any authority upon any custodial officer, except while he or she is on duty. (f) A custodial officer may do all of the following: (1) Use reasonable force in establishing and maintaining custody of persons delivered to him or her by a law enforcement officer. (2) Make arrests for misdemeanors and felonies within the local detention facility pursuant to a duly issued warrant. (3) Release without further criminal process persons arrested for intoxication. (4) Release misdemeanants on citation to appear in lieu of or after booking.