(a) Notwithstanding any other law to the contrary and except as provided in this section, any person otherwise eligible to participate in the retirement system or in the optional retirement program established in the Optional Retirement Program for Employees of Public Institutions of Higher Education, compiled in chapter 25, part 2 of this title who enters service as a state employee or teacher on or after July 1, 2014, shall participate in the hybrid plan established under this part; provided, however, that any person who enters service with a state-supported institution of higher education on or after July 1, 2014, and who is exempt from the Fair Labor Standards Act (29 U.S.C. § 201 et seq.), may elect membership in the optional retirement program as provided in § 8-36-923 in lieu of the hybrid plan. In all cases of doubt, the state treasurer shall determine whether the person is eligible to participate in the optional retirement program.

(b) Any state employee or teacher who is a member of the retirement system or of the optional retirement program established in chapter 25, part 2 of this title on June 30, 2014, shall continue membership in the retirement system pursuant to the terms of chapters 34-37 of this title or in the optional retirement program pursuant to the terms of chapter 25, part 2 of this title, as applicable, that were in effect on June 30, 2014. Any person who reenters service as a state employee or teacher on or after July 1, 2014, having previously served as a state employee or teacher prior to July 1, 2014, and who has not otherwise lost membership in the retirement system pursuant to § 8-35-104(a)(1) or (a)(2) or in the optional retirement program shall continue membership in the retirement system pursuant to the terms of chapters 34-37 of this title or in the optional retirement program pursuant to the terms of chapter 25, part 2 of this title, as applicable, that were in effect on June 30, 2014. A person loses membership in the optional retirement program by either annuitizing that person's entire account, rolling the person's entire account balance over to another plan, or by taking a distribution of the person's entire account balance.

(c)

(1) Except as provided in subdivision (c)(6), membership in the hybrid plan or the optional retirement program, as applicable, shall not be required for any part-time state employee or part-time teacher who would otherwise be covered under this part, or for any state employee who has optional membership in the retirement system pursuant to chapters 34-37 of this title.

(2) Notwithstanding any other law to the contrary and except as provided in subdivision (c)(6), any person who becomes a part-time state employee or a part-time teacher on or after July 1, 2016, and who otherwise would be covered under this part, shall upon initial date of hire file an irrevocable election to become or not to become a participant in the hybrid plan or in the optional retirement program described in § 8-36-923, as applicable. Any person serving as a part-time state employee or part-time teacher on June 30, 2016, and who otherwise would be covered under this part, but who did not elect to participate in the hybrid plan or in the optional retirement program described in § 8-36-923, shall, by no later than October 31, 2016, file an irrevocable election to become or not to become a participant in the hybrid plan or in the optional retirement program described in § 8-36-923, as applicable. This subdivision (c)(2) shall not be construed to prohibit an eligible employee from making the elections authorized in chapter 25, part 2 of this title.

(3) Notwithstanding this subsection (c), § 8-35-109, or any other law to the contrary, any person who becomes a state judge, district attorney general, or member of the general assembly on or after July 1, 2016, and who has not otherwise maintained membership in the retirement system based on previous service as a state employee or teacher, shall, upon the initial date of taking office, file an irrevocable election to become or not to become a participant in the hybrid plan. Any person serving as a state judge, district attorney general, or member of the general assembly on June 30, 2016, and who is not a participant in the hybrid plan or who has not otherwise maintained membership in the retirement system based on previous service as a state employee or teacher, shall, by no later than October 31, 2016, file an irrevocable election to become a participant in the hybrid plan.

(4) Notwithstanding any other law to the contrary and except as provided in subdivision (c)(6), any member of the state election commission who has not otherwise maintained membership in the retirement system based on previous service as a state employee or teacher, shall, on the first day following completion of five (5) years of service on the commission, file an irrevocable election to become or not to become a participant in the hybrid plan. Any member of the state election commission who has completed a minimum of five (5) years of service on the commission as of June 30, 2016, and who is not a participant in the hybrid plan or who has not otherwise maintained membership in the retirement system based on previous service as a state employee or teacher, shall, by no later than October 31, 2016, file an irrevocable election to become or not to become a participant in the hybrid plan.

(5) The elections provided for in this subsection (c) shall be made in the manner prescribed by the retirement system and shall be filed with the retirement system. The elections provided for in this subsection (c) shall not include any option for the employee to have a cash or deferred election right with respect to designated employee contributions, and the employee contributions shall be picked up in accordance with § 8-36-904(b).

(6) Notwithstanding this subsection (c), any current or former member of the retirement system or of a superseded system who accepts, or is elected to, a position on or after July 1, 2018, for which membership in the hybrid plan is otherwise optional pursuant to this subsection (c) shall become a member of the hybrid plan as a condition of employment. This subdivision (c)(6) shall not apply to retired members of the retirement system or of a superseded system who return to service in a position covered by the retirement system as provided in § 8-36-805, § 8-36-810, § 8-36-818, or § 8-36-821.

(d) Any teacher as defined in § 8-34-101(49)(B) who is a member of the retirement system pursuant to § 8-35-101 shall have the option to transfer from the retirement system to the hybrid plan on a prospective basis; provided, that allowing such choice meets all applicable state and federal requirements, including § 414(h) of the Internal Revenue Code (26 U.S.C. § 414(h)), that are necessary for the retirement system to maintain its status as a qualified plan under the Internal Revenue Code. The election to transfer shall be made in the manner prescribed by the retirement system and filed with the retirement system. Any such election shall become effective on the first day of the month next following the month the election is filed with the retirement system, and shall be irrevocable. The actuarial value of accrued benefits earned prior to the effective date of the transfer shall be determined under the applicable provisions of the retirement system in effect on the date of the transfer. The teacher shall thereafter be subject to the applicable provisions of this part for all service rendered and compensation received by the teacher as a teacher with any elementary or secondary Tennessee public school system or as a future state employee.

(e) All provisions of chapter 25, part 2 and of chapters 34-37 of this title that are not inconsistent with this part shall continue to apply, as applicable, to participants in the hybrid plan or the optional retirement program.