Cal. Government Code § 31874.5

(a) Whenever the percentage of annual increase in the cost of living as of January 1 of each year as shown by the Bureau of Labor Statistics Consumer Price Index for All Urban Consumers exceeds a full 3 percent of the existing cost-of-living increase factor provided by any provision of this article, an additional 1 percent of the excess for each full 3 percent over the existing increase factor shall be applied to the retirement allowances, optional death allowances, or annual death allowances increased by any provision of this article. The increases in allowances resulting from the adoption of this section shall be used to offset any accumulated carryover balances under existing cost-of-living adjustments. The cost of implementing this section shall be prefunded commencing with the adoption of this section by the board of supervisors. The method of paying the cost of implementing this section may be mutually agreed to in a memorandum of understanding executed by the employer and employee representatives. The board of retirement shall conduct the actuarial studies to determine those costs. (b) This section shall not be operative in any county until it is adopted by a majority vote of the board of supervisors. (c) Notwithstanding subdivision (a), a memorandum of understanding regarding the application of the contributions of new members, as defined in subdivision (f) of Section 7522.04, towards paying the cost of the additional cost-of-living adjustment shall not conflict with the requirements of Section 7522.30 or as may be agreed to in accordance with Sections 7522.30 and 31631.