Mo. Rev. Stat. § 478.070 : COURTS — Circuit Courts —JUDGES AND JURISDICTION — Jurisdiction of circuit courts TEXT PDF The circuit courts shall have original jurisdiction over all cases and matters, civil and criminal. Such courts may issue and determine original remedial writs. § 478.070, RSMo RSMo 1939 § 2100, A. 1949 S.B. 1140, A.L. 1978 H.B. 1634 Effective 1/2/1979