THE SKINNY: Over the last decade, Missouri cannabis laws have evolved from a strict approach, with tough anti-drug laws in place and serious repercussions for even minor offenses, to adult-use legalization of the substance with very little regulations or safeguards in place.

Read on to dig into the evolution of the Missouri cannabis laws.

Missouri Marijuana Laws Before Legalization

Prior to 2014, Missouri was one of the strictest states when it came to cannabis. Offenders could be punished with jail time regardless of first offense or amount possessed.

In 2014 cannabis was partially decriminalized, eliminating jail time for first-time offenders possessing up to 10 grams of cannabis. A first offense was instead punishable as a class D misdemeanor and carried a fine of up to $1,000.

Understanding Missouri Medical Marijuana Laws

In 2018, medical cannabis was legalized. Article XIV of the Missouri Constitution “allows state-licensed physicians to recommend medical marijuana for certain qualifying conditions, provides patients the right to discuss possible benefits of medical marijuana and establishes a patient’s right to use medical marijuana under the supervision of a physician.” (source)

Qualifying conditions include cancer, epilepsy, glaucoma, intractable migraines that are unresponsive to other treatment, multiple sclerosis (MS), seizures, Parkinson’s disease, Tourette’s syndrome and certain debilitating psychiatric disorders if diagnosed by a state-licensed psychiatrist.

In Missouri, medical cannabis refers to any strain with a tetrahydrocannabinol (THC) content of greater than 0.3%. All approved patients must have a valid Missouri Department of Health and Senior Services (DHSS)-issued ID card. They are allowed to purchase no more than four ounces within a 30-day period, unless they have been approved for more than that amount by the DHSS. This is equivalent to 32 Missouri Marijuana Equivalency Units (MMEs). One MME is equivalent to 3.5 grams of marijuana, 1 gram of marijuana concentrate or 100 mg of THC-infused products. (source)

Cannabis remains illegal at the federal level. It is still classified as a Schedule I substance under the Controlled Substance Act of 1970, which means it is considered to have a high potential for dependency and no recognized medical use. For context, other Schedule I substances include ecstasy, heroin and LSD. (source)

Understanding Missouri Recreational Marijuana Laws

Missouri Amendment 3, the Marijuana Legalization Initiative, was passed in 2022 and legalizes the purchase, possession, consumption, use, delivery, manufacturing and sale of cannabis for personal use for adults over 21. This does not allow for the public use of cannabis, driving under the influence or using cannabis while a passenger in a car, or the use of cannabis in the workplace. Individuals over 21 can possess up to three ounces of cannabis, which is the same amount they are allowed to purchase in a single transaction. (source)

In general, just because it is legal for you to use cannabis safely on your own, that does not mean you can use it in public, give it to others or be free of discrimination for using it. In these respects, it should be treated in a manner similar to alcohol or tobacco.

As of February 2024, 24 states (plus the District of Columbia) have legalized the recreational adult use of cannabis. In those states, anyone over the age of 21, even if not a state resident, can buy cannabis from a dispensary. However, you cannot carry cannabis across state lines. This is true even if the other state has also legalized recreational cannabis. Remember: federal laws still say cannabis is illegal, and the federal government has jurisdiction when things cross state borders. (source)