Mo. Rev. Stat. § 67.305: Counties or cities not to arrest or punish for public intoxication.

No county or municipality, except as provided in section 67.310, may adopt or enforce a law, rule or ordinance which authorizes or requires arrest or punishment for public intoxication or being a common or habitual drunkard or alcoholic. No county or municipality may interpret or apply any law or ordinance to circumvent the provisions of this section.