If at any time the relief association's actuary certifies that the balance of the association's fund, together with future contributions by active members and contributions by the state, or the city, or both, and earnings thereon, will be inadequate to provide future prescribed benefits for active and inactive members and their beneficiaries, the board of trustees of the association, by majority vote, may decrease the benefits provided for in sections 18-11-15, 18-11-16, and 18-11-17 in accordance with actuarial recommendations to assure the solvency of the fund and subject to the following conditions:
Decisions of the board of trustees, made in good faith and based upon actuarial recommendations with respect to benefit adjustments under this section, are final and supersede any previous actions or bylaws of the association. The members of the board of trustees must be indemnified from the funds of the association for any claims or expenses of defending claims arising from decisions made in good faith and based upon actuarial recommendations under this section.
N.D.C.C. § 18-11-18