Mo. Rev. Stat. § 49.272
The county commission of any county of the first classification without a charter form of government and with more than one hundred thirty-five thousand four hundred but less than one hundred thirty-five thousand five hundred inhabitants, any county of the first classification without a charter form of government having a population of at least eighty-two thousand inhabitants, but less than eighty-two thousand one hundred inhabitants, any county of the first classification with more than one hundred four thousand six hundred but fewer than one hundred four thousand seven hundred inhabitants, any county of the first classification with more than one hundred ninety-eight thousand but fewer than one hundred ninety-nine thousand two hundred inhabitants, any county of the first classification with more than two hundred forty thousand three hundred but less than two hundred forty thousand four hundred inhabitants, and any county of the first classification with more than eighty-three thousand but fewer than ninety-two thousand inhabitants and with a home rule city with more than seventy-six thousand but fewer than ninety-one thousand inhabitants as the county seat, which has an appointed county counselor and which adopts or has adopted rules, regulations or ordinances under authority of a statute which prescribes or authorizes a violation of such rules, regulations or ordinances to be a misdemeanor punishable as provided by law, may by rule, regulation or ordinance impose a civil fine not to exceed one thousand dollars for each violation. Any fines imposed and collected under such rules, regulations or ordinances shall be payable to the county general fund to be used to pay for the cost of enforcement of such rules, regulations or ordinances.
§ 49.272, RSMo