Mo. Rev. Stat. § 67.200

67.200. Political subdivisions or corporations having over $100,000,000 assessed valuation may pension officers and employees — exceptions. — 1. Any political corporation or subdivision of this state, now having or which may hereafter have an assessed valuation of one hundred million dollars or more, except counties of the second class having a population in excess of sixty-five thousand but less than one hundred twenty thousand inhabitants, which adjoins a county of the first class with a charter form of government, which does not now have a pension system for its officers and employees adopted pursuant to state law, may provide by proper legislative action of its governing body for the pensioning of its officers and employees and the widows and minor children of deceased officers and employees and to appropriate and utilize its revenues and other available funds for such purposes.

2. In adopting a pension plan, such counties, other political corporations or political subdivisions may provide for different benefits and requirements for elected officers and appointed officers and employees.

(L. 1967 p. 140 § 1, A.L. 1973 H.B. 629, A.L. 1988 H.B. 1098)