Tennessee Code Title 8. Public Officers and Employees § 8-35-226

(1) The chief legislative body of the city, special school district, or county passes a resolution approved by a two-thirds ( 2/3 ) majority authorizing membership for such employees and accepting the liability therefor;

(2) Upon such authorization and assumption of the employer liability, any such employee who meets the requirements of § 8-35-203(a)(2)(A) and (B) is eligible to establish retirement credit for such periods of previous service as authorized for other employees of the city, special school district, or county;

(3) An employee establishing such prior service shall make a lump sum payment equal to the employee contributions the employee would have made had the employee been a member of the system during the period claimed, plus interest at the rate provided in § 8-37-214;  and

(4) Membership in the retirement system pursuant to this section is permitted only if the chief legislative body that has authorized retirement participation for its departments or instrumentalities extends such coverage to all nonparticipating departments and instrumentalities.  If such option is elected, then the remaining departments and instrumentalities shall participate under the conditions of § 8-35-201.

(b)(1) Upon becoming a vested member of the Tennessee consolidated retirement system, any employee of a city who was formerly an elected official of the city where such employee is so employed shall be eligible to establish retirement credit for such time such employee served as an elected official of the city if the following conditions are met:

(2) Any employee establishing such prior service must make a lump sum payment equal to the employee contributions such employee would have made had such employee been a member of the retirement system during the period claimed, plus interest at the rate provided in § 8-37-214.

(3) The retirement system shall not be liable for the payment of retirement allowances or other benefits on account of such employee or such employee's beneficiaries for which reserves have not been previously created from funds contributed by the city and/or by or on behalf of such employee.

(4) It is the legislative intent that the state shall realize no increased cost as a result of this section.  All costs associated with retirement coverage, including administrative costs, shall be the responsibility of the city legislative body.

(1) The member's retirement benefits are based on service and salary rendered in a position other than a position covered by this section;

(2) The member is not drawing disability retirement benefits under chapter 36, part 5 of this title;

(3) The member will continue to accrue salary and service credit while serving in a position covered under this section until the member's retirement from that position.  Upon the retirement system's receipt of a request from the member, the member will receive a second retirement allowance based on the member's salary and service credit accrued in a position covered under this section;  provided, that the member has separated from the position and is otherwise eligible for the retirement allowance.  The retirement payment plan and beneficiary selected by the member on the retirement application from the other employment position must be the same for the second retirement allowance and must not be changed or revoked, except as provided in chapter 36, part 6 of this title;

(4) The member must not return to work temporarily in a position covered by the retirement system pursuant to chapter 36, part 8 of this title until the member retires from all positions covered by the retirement system;  and

(5) Consistent with §§ 8-36-203 and 8-36-303, benefits paid under this subsection (f) that are based on service in a position other than a position covered under this section must be paid from the member's effective date of retirement, which may include retroactive payments.