Sec. 6.20. ERRONEOUS PAYMENTS OR OVERPAYMENTS. (a) If the pension system pays money to any person not entitled to the payment, whether by reason of an error of the pension system as to entitlement to or the amount of a benefit or otherwise, or an act or error of some other person, including the recipient of the payment, the recipient of the payment holds the funds to which the recipient was not entitled in constructive trust for the pension system and those funds are subject to demand by the pension system at any time.

(b) The recipient of an erroneous payment from the pension system shall repay to the pension system all funds associated with the erroneous payment.

(c) Subject to Subsection (e) of this section, the board may by rule adopt a procedure to enable the pension system to offset the future benefit or other payments of a recipient described by this section. In addition, the board may take any additional action, including the bringing of a lawsuit, the board considers necessary to recover an erroneous payment the pension system is entitled to under this section.

(d) If the pension system determines that a person is entitled to additional benefits as a result of an error made by the pension system, the pension system shall promptly pay the additional benefits owed.

(e) The board's correction procedures must comply with the Internal Revenue Service's Employee Plans Compliance Resolution System and Revenue Procedure 2016-51, including subsequent guidance.