In United States v. Hemani, the Supreme Court is considering the constitutionality of a federal law that prohibits the possession of firearms by any person who is “an unlawful user of” any controlled substance, including marijuana. Cato, joined by the Reason Foundation, filed a brief urging the Court to hold that the law violates the Second Amendment. The right to keep and bear arms for self-defense is fundamental, and an individual does not forfeit this right by engaging in the responsible use of cannabis.
The federal ban violates the Constitution because it is ahistorical, vague, and far too broad. First, routine abusers of alcohol are dangerous to a greater degree and in different ways than are cannabis users. Cannabis use has not traditionally been thought to authorize disarmament in the way habitual alcoholism did, and the eventual criminalization of marijuana had the hallmarks of a moral panic rather than a rational public safety judgment.
Next, the definition of who qualifies as an “unlawful user” is unconstitutionally vague. Government regulations say even a single use of a drug within a calendar year is enough to justify disarmament. At the Supreme Court, the government alternately defines “unlawful user” as one who “engages in the habitual or regular use of a controlled substance” and has “a habit of using drugs unlawfully.” The government’s varying definitions lack precision because the statute is imprecise—too imprecise to satisfy the Constitution.
Lastly, the federal ban threatens to deny constitutional rights to a staggering number of Americans. Under the government’s interpretation of the law, one out of every five Americans presently has no right to keep and bear arms, and one out of every two should have been stripped of their Second Amendment rights at some point in their lives. Incredibly, the government is making this argument even though the president just signed an executive order recognizing that medical marijuana use can be compatible with responsible citizenship.
If courts can suspend “the constitutional rights of so many for such common behavior,” something has gone awry. The Second Amendment’s command is timeless and clear: people have a fundamental right to keep and bear arms that does not yield to empirically baseless fabulism or extravagant distortions of history.