Mo. Rev. Stat. § 77.340
The mayor may, with the consent of a majority of all the members elected to the city council, remove from office, for cause shown, any elective officer of the city, such officer being first given opportunity, together with his witnesses, to be heard before the council, sitting as a court of impeachment. Any elective officer may, in like manner, for cause shown, be removed from office by a two-thirds vote of all the members elected to the city council, independently of the mayor's approval or recommendation. The mayor may, with the consent of a majority of all the members elected to the council, remove from office any appointive officer of the city at will; and any such appointive officer may be so removed by a two-thirds vote of all the members elected to the council, independently of the mayor's approval or recommendation. The council may pass ordinances regulating the manner of impeachment and removals.
§ 77.340, RSMo
RSMo 1939 § 6875