Missouri constitution
Article VI: local government
Section 25

No county, city or other political corporation or subdivision of the state shall be authorized to lend its credit or grant public money or property to any private individual, association or corporation except as provided in Article VI, Section 23(a) and except that the general assembly may authorize any county, city or other political corporation
or subdivision to provide for the retirement or pensioning of its officers and employees and the surviving spouses and children of deceased officers and employees and may also authorize payments from any public funds into a fund or funds for paying benefits upon retirement, disability or death to persons employed and paid out of any public fund for educational services and to their beneficiaries or estates; and except, also, that any county of the first class is authorized to provide for the creation and establishment of death benefits, pension and retirement plans for all its salaried employees, and the surviving spouses and minor children of such deceased employees; and except also, any county, city or political corporation or subdivision may provide for the payment of periodic cost of living increases in pension and retirement benefits paid under this section to its retired officers and employees and spouses of deceased officers and employees, provided such pension and retirement systems will remain actuarially sound.