(a) The provisions of this subtitle shall be interpreted and administered in a manner that permits the retirement system's benefit plan to be considered a qualified plan under Section 401, Internal Revenue Code of 1986 (26 U.S.C. Section 401). The board of trustees may adopt rules necessary to accomplish that purpose, and those rules are considered a part of the plan.
(b) The retirement system's benefit plan shall be considered the primary retirement plan for members of the retirement system in determining qualification status under Section 401(a), Internal Revenue Code of 1986 (26 U.S.C. Section 401(a)).