Mo. Rev. Stat. § 115.646
No contribution or expenditure of public funds shall be made directly by any officer, employee or agent of any political subdivision, including school districts and charter schools, to advocate, support, or oppose the passage or defeat of any ballot measure or the nomination or election of any candidate for public office, or to direct any public funds to, or pay any debts or obligations of, any committee supporting or opposing such ballot measures or candidates. This section shall not be construed to prohibit any public official of a political subdivision, including school districts and charter schools, from making public appearances or from issuing press releases concerning any such ballot measure. Any purposeful violation of this section shall be punished as a class four election offense.
§ 115.646, RSMo