California Code, Government Code - GOV § 31672.2

(a) An elective officer who filed a declaration with the board to become a member, pursuant to Section 31553, who has served two complete consecutive terms in an elective office, and who has reached the minimum age for retirement provided in Section 31672, may be retired upon filing with the board a written application setting forth the date upon which the member desires the member's retirement to become effective.The effective retirement date shall not be either of the following:

(b) This section shall become operative only in any county of the 16th class, as defined by Section 28020 and 28037, as amended by Chapter 1204 of the Statutes of 1971, and on the first day of the calendar month after the board of supervisors adopts a resolution making it operative in the county.

(c) This section shall not apply to an elective officer who is subject to the provisions of the California Public Employees' Pension Reform Act of 2013 for all or any portion of the elective officer's membership in the county retirement system.