Tenn. Code § 17-319
Membership in the retirement system herein provided shall be optional with each judge. For the purpose of providing further funds with which to pay the retirement or disability compensation provided for in §§ 17-313 - 17-323, every judge who desires to avail himself of the benefits of said sections shall contribute to the judges' retirement fund an amount annually equal to three per cent (3%) of his gross annual salary as judge, such contributions to begin on or after April 26, 1955, or upon the appointment or election of such judge thereafter. This contribution shall be made in equal monthly instalments, which the commissioner of finance and administration shall deduct from the monthly compensation of such judge and credit the same to the judges' retirement fund. Every judge in office on April 26, 1955, who desires to come under the provisions hereof, shall notify the director of accounts, by registered return-receipt mail on or before September 1, 1958. All judges elected or appointed after April 26, 1955, shall elect whether or not to come under the provisions of §§ 17-313 - 17-323 within sixty (60) days after such appointment or election. Every judge electing to come under the provisions of said sections shall continue his contributions to the judges' retirement fund, as herein provided, as long as he remains in office.
Any judge in office on April 15, 1970, who did not comply with the provisions of this section by giving the notice above required and who, as the result, has lost service credit, may, on or before December 1, 1970, notify the commissioner of finance and administration of his desire for such credit, reciting in his notice the period for which he seeks credit, and shall remit to the treasurer of the state the amounts that would have been deducted from his salary for such period had he given the notice as provided above, together with interest thereon at the rate of six per cent (6%) per annum. Thereupon the judge shall be entitled to service credit for such period. Such a judge shall be considered to be a member of the system on April 15, 1970, and entitled to the credit for service provided for in Section 17-313(c) and he shall not be subject to the provision for late retirement.
Any person who serves as executive secretary of the Supreme Court and who was a participant in the judges' retirement system prior to his appointment as executive secretary shall continue as a member of the judges' retirement system and required to contribute to the judges' retirement fund in respect of every year, past and future, that he receives credit for service under this chapter during the time he is executive secretary in the same amount and manner as though he were a member of this judges' retirement system for all such service, and he shall not, by reason of participating in this judges' retirement system be eligible to receive benefits from any other retirement plan of the state of Tennessee. Provided further, any contributions made by such person to any other state retirement system shall be transferred from the other retirement system and paid into the judges' retirement system. Such person shall receive credit in the judges' retirement system for the service and period of time which such person had in the other retirement system.
T.C.A. § 17-319