California Code, Government Code - GOV § 20840

(a) Notwithstanding Sections 20616, 20618, and 20815, the board may create, combine or eliminate risk pools for local miscellaneous members and local safety members.

(b) The board shall establish, by regulation, the criteria under which contracting agencies shall participate in a risk pool and the criteria under which contracting agencies, county offices of education, school districts, and community college districts may participate in a risk pool.  The criteria shall specify that county offices of education, school districts, and community college districts may only participate in a risk pool if the retirement formula of the risk pool is higher than the retirement formula applicable to school members.  In determining the criteria, the board shall consider the expected variability of the employer contribution rate due to demographic events.  In no event shall contracting agencies with more than 100 active members in a member classification be required to commence participation in a risk pool for members in that member classification.  For the purpose of this subdivision an active member is a member who is an employee of the contracting agency.

(c) If a contracting agency, county office of education, school district, or community college district participates in a risk pool, the assets and liabilities with respect to the affected member classification shall be combined with those of the risk pool.

(d) The board shall establish, by regulation, the circumstances under which a contracting agency may cease participation in a risk pool for a member classification.

(e) All of the following provisions shall apply, without election by the contracting agency participating in a risk pool, to local members included in a risk pool: