Mo. Rev. Stat. § 36.157: Prohibitions on political activities by state employees.

An employee may not engage in political activity:

(1) While on duty;

(2) In any room or building occupied in the discharge of official duties;

(3) By utilizing any state resources or facilities;

(4) While wearing a uniform or official insignia identifying the office or position of the employee; or

(5) When using any vehicle owned or leased by the state or any agency or instrumentality of the state.