Mo. Rev. Stat. ยง 543.210
543.210 Jury โ number โ selection.
543.210. Jury โ number โ selection. โ If the case is thereafter tried before an associate circuit judge, the jury shall be composed of twelve persons, unless a less number shall be agreed upon, but not less than six. The selection of the jury and the practice and procedure relative to the jury in a case tried before an associate circuit judge shall be the same as in a case tried before a circuit judge except as otherwise provided herein.
(RSMo 1939 ยง 3826, A.L. 1945 p. 750 ยง 21, A.L. 1978 H.B. 1634) Prior revisions: 1929 ยง 3436; 1919 ยง 3781; 1909 ยง 4989 Effective 1-02-79