Mo. Rev. Stat. § 87.125

87.125. Authorizing municipality to provide by ordinance for pensions. — Any city in this state that now has or may hereafter have seven hundred thousand inhabitants or more and that has an organized fire department is hereby authorized, subject to the provisions of sections 87.120 to 87.370 , to provide by ordinance for the pensioning of members of any such organized fire department and of the dependents of deceased members thereof and to take from its municipal revenue a fund for such purpose. The fund shall be under the management of a board of trustees herein described and shall be known as "The Firemen's Retirement System of ______" and by such name all of its business shall be transacted, all of its funds invested and all of its cash and securities and other property held.

(L. 1943 p. 708 § 2, A.L. 1959 S.B. 314 § 86.483) (1973) Held, this section is permissive and a city ordinance passed in accordance with it is neither void nor automatically amended by an amendment to such enabling legislation. Trantina v. Board of Trustees of Firemen's Retirement System of St. Louis, et al. (A.), 503 S.W.2d 148.