O'Fallon, MO Public Conduct: Public Marijuana Use (2026)

545, added by Ordinance No. 7004 on March 9, 2023, layers City rules on top of the marijuana legalization created by Article XIV of the Missouri Constitution. Subsection (A) bans possessing or consuming marijuana, or possessing marijuana accessories, on the grounds of any public or private preschool, elementary or secondary school, institution of higher education, on a school bus, or on the grounds of any correctional facility including a jail or detention facility. Subsection (B) bans consuming or smoking marijuana while operating, being in physical control of, or being in a motor vehicle, train, aircraft or motorboat while it is operating.

Subsection (C) is the general public-use ban: consuming marijuana in a public area, including parks, playgrounds, recreation facilities, festivals, parades, sports arenas, and other areas open to public gathering and access, is unlawful. That subsection carries one narrow carve-out: it does not stop City restaurants from preparing and serving marijuana-infused culinary dishes or beverages for on-site, same-day consumption. 530, which allows adults 21 and older to possess marijuana only in the quantities Article XIV permits.