19-2-715. Purchase of Montana public service. (1) (a) An active member may, at any time before retirement, file a written application with the board to purchase as service credit in the member's retirement system all or any portion of the member's previous service credit in the public employees', judges', highway patrol officers', sheriffs', game wardens' and peace officers', firefighters' unified, or municipal police officers' retirement system if the member has:

(i) received or is eligible to receive a refund of accumulated contributions; and

(ii) become a member of one of the other retirement systems covered under chapter 3, 5, 6, 7, 8, 9, or 13 of this title.

(b) To purchase this service credit, the member shall pay the actuarial cost of the service credit in the member's current retirement system, based on the system's most recent actuarial valuation and the annual compensation of the member, minus the employer contribution provided in subsection (1)(c).

(c) Upon receiving the member's payment under subsection (1)(b), the board shall transfer from the member's former retirement system to the member's current retirement system an amount equal to the employer contributions made on compensation during the member's former service, but no more than an amount equal to the normal cost contribution rate minus the employee contribution rate in the member's current retirement system according to the system's most recent actuarial valuation.

(d) If the member was formerly in the public employees' retirement system's defined contribution plan, the member shall pay the actuarial cost of the service credit in the member's current retirement system based on the system's most recent actuarial valuation and the annual compensation of the member. The member is eligible to transfer the vested portion of the member's defined contribution account to pay the balance due. Any nonvested portion of the defined contribution account is forfeited pursuant to 19-3-2117.

(2) (a) An active member may, at any time before retirement, file a written application with the board to purchase all or a portion of previous employment for the state or a political subdivision of the state. The member shall provide salary and employment documentation certified by the member's former public employer. To purchase service credit under this section, the member shall pay the actuarial cost of the service credit in the member's current retirement system, as determined by the board, based on the system's most recent actuarial valuation. For the purpose of this subsection (2)(a), a political subdivision of the state includes a school district.

(b) The board is the sole authority under subsection (2)(a) in determining what constitutes public service, subject to 19-2-403.