Missouri voters legalized medical marijuana in 2018. Voters legalized recreational marijuana in 2022. The result is that millions of Missourians can now lawfully purchase, possess, and use cannabis under state law. Federal law, however, has not changed. And federal law — specifically the Gun Control Act of 1968 — still treats every marijuana user as a "prohibited person" who cannot lawfully buy, own, or possess a firearm.
This is not a hypothetical conflict. Federal Form 4473, the questionnaire every American fills out when buying a gun from a licensed dealer, asks directly: "Are you an unlawful user of, or addicted to, marijuana?" The form notes — in bold — that "the use or possession of marijuana remains unlawful under Federal law regardless of whether it has been legalized or decriminalized for medicinal or recreational purposes in the state where you reside." Lying on that form is a federal felony. Answering truthfully — yes — disqualifies the buyer from purchasing the gun.
The implications for Missouri medical marijuana cardholders are sweeping, and most cardholders we talk to have no idea about them. This article walks through what the law actually says, what the practical consequences are, and what your options are if you find yourself caught between a state-issued medical card and a federally enforced prohibition.
The federal law: 18 U.S.C. §922(g)(3)
Federal firearms law makes it unlawful for any person who is "an unlawful user of or addicted to any controlled substance" to ship, transport, possess, or receive any firearm or ammunition. Marijuana is a Schedule I controlled substance under federal law. The Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) has stated repeatedly — most explicitly in a 2011 letter to all federal firearms licensees — that any use of marijuana, including state-authorized medical use, makes the user a "prohibited person" under §922(g)(3).
The penalty for violating §922(g)(3) is up to ten years in federal prison. The penalty for lying on Form 4473 (a violation of §922(a)(6)) is also up to ten years.
What this means in practice
For Missouri medical marijuana cardholders, the practical realities break down into four categories:
Buying a gun from a licensed dealer. If you answer "yes" to the marijuana question on Form 4473, the dealer must refuse to sell you the gun. If you answer "no," you have committed a federal felony at the moment you sign the form. There is no third option that complies with the law.
Owning guns you already had before getting your card. This is the most common scenario. Cardholders frequently have firearms they purchased lawfully years before they ever applied for a medical card. The federal statute does not grandfather them in — once you become a medical marijuana user, ongoing possession of firearms violates §922(g)(3). The day you renew your card, you are in continuing violation of federal law.
Living with a household firearm. A spouse or partner who uses medical marijuana while another household member owns the firearms creates a "constructive possession" issue. ATF and federal courts treat shared access to a firearm — keys to a gun safe, a shotgun in the closet, a handgun in a nightstand both spouses can reach — as possession by both parties. If one spouse is a medical marijuana cardholder, the cardholder can be charged with §922(g)(3) for the household guns.
Concealed-carry permits. Missouri's concealed-carry application includes federal eligibility questions. Missouri has not consistently denied permits to medical marijuana cardholders, but the federal-law disability still attaches whether the state permit issues or not.
The practical reality of enforcement
Federal prosecutors do not bring §922(g)(3) cases against medical marijuana users at scale. There are too many users, the cases are politically unpopular, and federal prosecutorial resources are concentrated on more serious offenses. The realistic risk of being prosecuted simply for being a cardholder who owns a gun is low.
The risk becomes real, however, in two recurring scenarios.
The traffic stop. A medical marijuana cardholder is pulled over with a firearm in the car. The marijuana is in the cup holder, the gun is in the glove box. State law has no problem with either. Federal law has a serious problem with the combination. Federal charges in this scenario are not common, but they happen — particularly where state authorities refer the case to federal prosecutors.
The unrelated arrest. A cardholder is arrested on an unrelated charge — a DWI, a domestic disturbance, a drug-paraphernalia offense — and the arresting officers find both marijuana and a firearm at the scene. The federal charge becomes a stacking opportunity for the prosecutor and a leverage point in plea negotiations.
The legal exposure is real, but it is manageable with planning. The two most consequential decisions are: (1) whether to renew your card, and (2) where and how your firearms are stored. Both should be made with counsel, not on assumption. Call us at (314) 831-9350 for a confidential conversation.
Your realistic options
There are four practical paths Missouri cardholders take, each with trade-offs.
Option 1: Don't get the card. Missouri's recreational legalization makes a medical card largely unnecessary for most patients — the same products are available without it. Foregoing the card removes the federal disability for the people who would otherwise be cardholders only.
Option 2: Let the card expire. Federal "use" status is not based on holding a card — it is based on actual use. But the card is the most reliable evidence the government would have. Letting it expire and ceasing use creates a clean break for someone who decides the firearms matter more.
Option 3: Transfer the firearms. Some cardholders transfer their firearms to a family member's possession (out of the cardholder's house, out of any safe the cardholder can access), at least temporarily. Done properly, this removes the §922(g)(3) exposure for the cardholder. Done improperly — with the cardholder still having keys to the safe — it does not.
Option 4: Live with the risk. The least satisfying option, but the one many cardholders effectively choose by inaction. Federal enforcement is rare in the absence of an unrelated case. The risk is real but low — until something else triggers it.
The legal landscape is changing — but slowly
Several federal courts have ruled §922(g)(3) unconstitutional as applied to medical marijuana users in the wake of New York State Rifle & Pistol Association v. Bruen (2022). Other courts have ruled the opposite way. The Supreme Court has not resolved the split. Until it does, federal law remains formally enforceable everywhere.
Congress has periodically considered legislation to clarify or repeal §922(g)(3) as applied to state-legal cannabis users. Nothing has passed. There is no realistic timeline for federal reform.
For now, every Missouri cardholder who owns a gun should know exactly where they stand. The intersection of state cannabis law and federal firearms law is one of the few areas where two perfectly lawful activities under one set of rules combine into a felony under another.
What to do if you are facing a federal firearms charge
Federal cases are different from state cases. The procedures are different, the standards are different, the prosecutors are different, and the stakes are higher. If you have been arrested or interviewed by federal agents about a firearms charge involving marijuana use, the most important thing you can do is engage counsel before you say anything else. Federal investigations move quietly and quickly; the difference between a charge and no charge is often a single conversation that should not have happened.
For more on our approach to criminal defense generally, see our practice-area page. For answers to common questions clients ask, see our FAQ.
State law and federal law have not caught up to each other on cannabis. Until they do, every Missouri medical marijuana cardholder who also owns a firearm is living in the gap. Knowing where the gap is matters.
This article is general legal information for Missouri residents. It is not legal advice. Missouri law changes regularly — statutes are amended, case law evolves, and the application of any rule depends on the specific facts of each case. Do not act, or refrain from acting, based on this article without consulting a qualified Missouri attorney about your particular situation. Reading this article does not create an attorney-client relationship. For advice on your specific case, contact David Naumann & Associates at (314) 831-9350. The initial consultation is free. See the full Legal Disclaimer for complete terms.