Mo. Rev. Stat. § 326.125
At all proceedings for the enforcement of these or any other provisions of this chapter the board shall, as it deems necessary, select, in its discretion, either (1) the attorney general or one of his assistants designated by him or (2) other legal counsel to appear and represent the board at each stage of such proceeding or trial until its conclusion.
(L. 1943 p. 955 § 14911m, A.L. 1967 p. 428, § 326.120(13), A.L. 1977 S.B. 100)