A federal appeals court has ruled that an existing federal ban on the sale of guns to holders of medical marijuana cards does not violate the Second Amendment of the U.S. Constitution, which prohibits infringement of the right to keep and bear arms. The ruling pertains to the nine states under the jurisdiction of the 9th U.S. Circuit Court of Appeals: Alaska, Arizona, California, Hawaii, Idaho, Montana, Nevada, Oregon, and Washington. Of those nine, only Idaho hasn’t legalized medical marijuana, which, as far as the federal government is concerned, remains illegal everywhere in the U.S. regardless of state laws.

The specific case was a lawsuit brought by a Nevada plaintiff, S. Rowan Wilson, who said a gun store refused to sell her a weapon after she obtained a medical marijuana card in 2011. At issue was the assumption that possession of such a card is reasonable cause to presume that the holder actually uses the drug (Wilson claims she doesn’t). The appeals court ruled that it is, in fact, an “eminently reasonable” assumption:

Wilson flatly maintains that she is not an unlawful drug user and is instead challenging a set of laws that bar non-drug users from purchasing firearms if there is only reasonable cause to believe that they are unlawful drug users, for instance, if they hold a registry card. Wilson correctly points out that the degree of fit between these laws and the ultimate aim of preventing gun violence is not as tight as the fit with laws like 18 U.S.C. § 922(g)(3), which affect only illegal drug users. Nonetheless, the degree of fit between 18 U.S.C.§ 922(d)(3), 27 C.F.R. § 478.11, and the Open Letter and the aim of preventing gun violence is still reasonable, which is sufficient to survive intermediate scrutiny. The connection between these laws and that aim requires only one additional logical step: individuals who firearms dealers have reasonable cause to believe are illegal drug users are more likely actually to be illegal drug users (who, in turn, are more likely to be involved with violent crimes). With respect to marijuana registry cards, there may be some small population of individuals who–although obtaining a marijuana registry card for medicinal purposes–instead hold marijuana registry cards only for expressive purposes. But it is eminently reasonable for federal regulators to assume that a registry cardholder is much more likely to be a marijuana user than an individual who does not hold a registry card.

The decision reaffirms the federal government’s position that marijuana is a controlled substance whose use is unlawful regardless of state laws authorizing it for medical purposes. The marijuana legalization advocacy group NORML responded to the ruling with this statement from deputy director Paul Armentano: