Missouri constitution
Article V: judicial department
Section 16

Each county shall have such
number of associate circuit judges as provided by law. There shall be at least one resident
associate circuit judge in each county. Associate circuit judges shall be selected
or elected in each county. In those circuits where the circuit judge is selected under
section 25 of article 5 of the constitution the associate circuit judge shall be selected
in the same manner. All other associate circuit judges shall be elected in the county in
which they are to serve.