California Code, Government Code - GOV § 27772

(a) Except as provided in Section 69906.5, the chief probation officer may appoint deputies, assistants, and other persons, and their compensation shall be established according to the provisions of the county's merit systems or civil service systems. If no merit systems or civil service systems exist in the county, the board of supervisors shall provide for appointment, removal, and compensation of this personnel.

(b) A deputy or assistant to the chief probation officer shall not have authority to act until his or her appointment has been approved by the juvenile justice commission or regional juvenile justice commission and by the presiding judge or majority of judges. The term of office of a deputy or assistant shall expire with the term of the chief probation officer who appointed the deputy or assistant, but the chief probation officer may revoke and terminate the appointment at any time.

(c) This section applies in any charter county with a charter establishing the office of chief probation officer or adult probation officer and provides for the appointment of the officer in accordance with general law, subject to the merit system provisions of the charter.