Cal. Government Code § 75031.5

(a) A judge may elect, in writing filed with the Judges’ Retirement System, to make contributions and receive service credit in this system for active service, performed prior to entering the system, of not less than one year in the Armed Forces of the United States or not less than one year in the Merchant Marine of the United States prior to January 1, 1950, excluding any period of that active service for which the judge is receiving, or is entitled to receive, a retirement allowance from any other retirement system supported wholly or in part by public funds. The service credit for that service may be granted on the basis of one year of credit for each year of credited service in this system, but may not exceed a total of four years of service credit regardless of the number of years of either that service or subsequent judicial service. A judge electing to receive credit for that service shall have at least one year of judicial service credited on the date of election or the date of retirement. If the service described in this subdivision terminated with a dishonorable discharge, service credit in the system may not be granted under this section. (b) For purposes of this section, a judge means a judge as defined in Section 75002 or a judge who has retired pursuant to Section 75025 or has elected a deferred retirement subject to Section 75033.5. (c) The retirement allowance of a retired judge who elects to receive service credit pursuant to this section shall be increased only with respect to the allowance payable on and after the date of election. (d) A judge who elects to receive credit for service pursuant to this section shall contribute to the Judges’ Retirement Fund a sum equal to the actuarial present value of the increase in benefits due to the additional service, as determined by the chief actuary and approved by the board. (e) An election by a judge to receive credit for service under this section shall be effective only if accompanied by a lump-sum payment or an authorization for payment, other than a lump-sum payment, in accordance with regulations adopted by the board.