Missouri Revised Statutes Title XXXVIII. Crimes and Punishment; Peace Officers and Public Defenders § 577.709. Vulgar or profane language--passenger under influence of alcohol or drugs, penalties, exceptions--driver may remove passenger from bus, when

(1) To threaten a breach of the peace or use any obscene, profane, or vulgar language;

(2) To be under the influence of alcohol, unlawfully under the influence of a controlled substance, to ingest or have in his possession any controlled substance unless properly prescribed by a physician or medical facility, or to drink intoxicating liquor of any kind in or upon any passenger bus except a chartered bus;

(3) To fail to obey a reasonable request or order of a bus driver or any duly authorized company representative.