California Code, Government Code - GOV § 53622

(1) Solely in the interest of, and for the exclusive purposes of providing benefits to, participants in the retiree health benefit plan, minimizing employer contributions thereto, and defraying reasonable expenses of administering the plan.

(2) With the care, skill, prudence, and diligence under the circumstances then prevailing that a prudent person acting in a like capacity and familiar with these matters would use in the conduct of an enterprise of a like character and with like aims.

(3) Shall diversify the investments of the funds so as to minimize the risk of loss and to maximize the rate of return, unless under the circumstances it is clearly prudent not to do so.