Gun purchases are off limits in the U.S. to anyone who uses medical marijuana or holds a state-approved medicinal marijuana card, a federal appeals court ruled Wednesday, accepting the government's view that illegal-drug users are prone to violence, reports the San Francisco Chronicle.

Although medical-marijuana use is legal in California, 24 other states, and Washington, D.C., the federal government still bans all use of the drug, and in 1968 Congress prohibited illegal-drug users and addicts from buying and possessing firearms.

On Wednesday, the Ninth U.S. Circuit Court of Appeals in San Francisco said the Bureau of Alcohol, Tobacco, Firearms and Explosives properly relied on that law in a September 2011 "open letter" to all licensed gun dealers forbidding sales to anyone who "uses or is addicted to marijuana," even in states that have legalized the drug for medical purposes.