Cal. Government Code § 7522.52

(a) In any fiscal year, a public employer’s contribution to a defined benefit plan, in combination with employee contributions to that defined benefit plan, shall not be less than the normal cost rate, as defined in Section 7522.30, for that defined benefit plan for that fiscal year. (b) The board of a public retirement system may suspend contributions when all of the following apply: (1) The plan is funded by more than 120 percent, based on a computation by the retirement system actuary in accordance with the Governmental Accounting Standards Board requirements that is included in the annual valuation. (2) The retirement system actuary, based on the annual valuation, determines that continuing to accrue excess earnings could result in disqualification of the plan’s tax-exempt status under the provisions of the federal Internal Revenue Code. (3) The board determines that the receipt of any additional contributions required under this section would conflict with its fiduciary responsibility set forth in Section 17 of Article XVI of the California Constitution.