Mo. Rev. Stat. § 286.020
The term of office of each member of the commission shall be six years except that when first constituted one member shall be appointed for two years, one for four years and one for six years, and thereafter all vacancies shall be filled as they occur. The terms of office of the first members of the commission shall begin on the date of their appointment which shall be within thirty days after the effective date of this chapter. Any member appointed to fill a vacancy occurring prior to the expiration of the term for which the member's predecessor was appointed, shall be appointed by the governor, by and with the advice and consent of the senate, for the remainder of such term. The governor may remove any member of the commission, after notice and hearing, for gross inefficiency, mental or physical incapacity, neglect of duties, malfeasance, misfeasance or nonfeasance in office, incompetence or for any offense involving moral turpitude or oppression in office.
(L. 1945 p. 1101 § 2, A.L. 1995 H.B. 300 & 95)