If, after December 31, 1957, and either before or after retirement a member dies leaving a spouse and has not designated a beneficiary, and, prior to the payment of any portion of the death benefit, such spouse files with the board written evidence, satisfactory to the board, that she or he is the surviving spouse and the date of the marriage, such surviving spouse shall be deemed, for the purposes of this chapter, to have been nominated as the beneficiary by such member.
Ca. Gov. Code § 31458.2