(a) Any member may elect to have included in the member's creditable service, years of service as an employee of another municipality, as a State employee, or as a teacher in a public or private school, as defined by the Board, and years of service in the defined contribution plan authorized under section 5070 of this title when the employee elects to transfer back to the defined benefit plan as a result of his or her employer offering a higher group plan. Any member who so elects shall deposit in the Fund by a single contribution the amount or amounts determined by the System's actuary to be cost neutral to the System. No application for credit under this subsection shall be granted if at the time of application, the member has a vested right to retirement benefits in another defined benefit retirement system based upon that service.

(b) Any member who has rendered 15 years of creditable service and who has, prior to becoming a member of the System, served a minimum of one full year of full-time service in the military or one full year of full-time service as a member of the Cadet Nurse Corps in World War II, the Peace Corps, VISTA, or AmeriCorps for which the member has derived no military pension benefits, may elect to have included in the member's creditable service all or any part of the member's military, Cadet Nurse Corps, Peace Corps, VISTA, or AmeriCorps service not exceeding five years. Any member who so elects shall deposit in the Fund by a single contribution the amount or amounts determined by the System's actuary to be cost-neutral to the System. Notwithstanding the foregoing, in the event of a conflict between the provisions of this subsection and the provisions of 10 U.S.C. § 12736 concerning the counting of the same full-time military service toward both military and State pensions, the provisions of the U.S. Code shall control.

(c) Any time a member is required to make a single contribution in connection with an election under this section, a member may contribute over a maximum of five years in installments of equal value. Those contributions shall become a part of the member's accumulated contributions. Any member who retires before completing payment for the purchase of service under this section shall receive pro rata credit for service purchased before the date of retirement, but if the member so elects at the time of retirement, the member may pay as much in a single sum as is necessary to provide full credit at that time. (Added 1999, No. 53, § 8b; amended 2001, No. 29, § 9; 2005, No. 197 (Adj. Sess.), § 2; 2007, No. 13, § 40; 2009, No. 24, § 10; 2015, No. 18, § 8.)