Section 21090 Of Article 3. Second Tier Retirement—contracting Agencies From California Government Code >> Division 5. >> Title 2. >> Part 3. >> Chapter 12. >> Article 3.

. (a) The governing body of a contracting agency may establish a two-tiered retirement system developed by the board .
  (b) It is the intent of the Legislature to make a two-tiered retirement system a matter for bargaining pursuant to provisions of law relating to employer-employee relations.