Mo. Rev. Stat. § 546.040
All issues of fact in any criminal cause shall be tried by a jury, to be selected, summoned and returned in a manner prescribed by law.
(RSMo 1939 § 4051)
Prior revisions: 1929 § 3662; 1919 § 4005; 1909 § 5212
CROSS REFERENCE:
Defendant may waive trial by jury, when, Const. Art. I § 22(a)