In September 2016, a federal appeals court covering nine western states upheld a ban on firearms sales to residents who hold medical marijuana cards.

Though Colorado was not among those states, lawyers here say the move sends a signal that the federal judicial branch is not sympathetic to state laws when it comes to guns and pot.

The ruling stemmed from a lawsuit brought by a Nevada woman with a medical marijuana card— she says she’s not a user— who was denied a gun by a gun dealer. The court decision is again fueling a debate about the intersection of state and federal law on weed and weapons.

“We’ve had this problem from day one,” says Tony Fabian, an attorney who has helped draft firearms legislation in Colorado.

“There’s nothing in Colorado law that says that it is unlawful to be in possession of a legal amount of marijuana and have a firearm,” Fabian told The Colorado Independent. “The problem is the dichotomy in federal and state law. And the feds are much more restrictive when it comes to firearms ownership.”

Colorado law is silent about whether someone of the appropriate age can carry a legal firearm and a legal amount of marijuana at the same time, says John Jackson, the chief of police for Greenwood Village and a former director of the state police chief’s association.

“If they’re 21 and they’ve got a joint, and a gun on their hip, there’s no issue there,” he said. (Colorado is also an open-carry state.)

The feds have a different take.

“Under federal law, a marijuana user cannot legally possess a firearm,” Lisa Meiman, a spokeswoman for the Denver division of the federal Bureau of Alcohol, Tobacco, Firearms and Explosives, told The Independent. Not even in Colorado where marijuana is legal to have and use.

So, local Colorado police don’t mind, but a federal agent might. The problem is also compounded because the administration of Democratic President Barack Obama has directed federal agencies not to zealously enforce some federal laws in states that have legalized marijuana.

The difference between state and federal law has frustrated some firearms enthusiasts in Colorado since the state legalized the sale and possession of recreational marijuana with a constitutional amendment passed by voters in 2013. The disconnect between laws and agencies grows wider when it comes to concealed-carry permits because county sheriffs’ ask applicants if they are marijuana users. A “yes” answer means no permit.

“Of course you can drink booze, but no devil’s cabbage,” says Isaac Chase, a Colorado Springs firearms instructor and co-founder of a group called Guns for Everyone.

Last year, Chase’s group tried unsuccessfully to gather enough signatures for a ballot initiative that would change the concealed-carry application process. Students in his training classes kept asking about the marijuana issue, he said.

Related: Colorado gun culture weighs cannabis carry and constitutional carry

Buying a gun here — no matter how you carry it — requires filling out a form, which asks several questions, including whether the buyer is an unlawful user of marijuana. The Colorado Bureau of Investigation uses a system called InstaCheck and runs information through the National Instant Criminal Background Check system, or NICS. The bureau also runs background checks for county sheriff’s offices for those applying for concealed weapons permits. But InstaCheck does not access medical marijuana information in the background check, CBI spokeswoman Susan Medina told The Independent.

So, says Boulder attorney Jeff Gard, who practices marijuana law, “the bottom line is but for your own disclosure of that information, there is no way [for a gun dealer] to know,” whether a gun buyer is a medical marijuana card holder.

And here’s something else: Because the 9th Circuit doesn’t cover Colorado, it’s possible for a similar case to pop up in the 10th Circuit, which does cover this state.

Gard offers this potential scenario: What if a botanist who doesn’t use marijuana decides to grow the legally allowed limit of six pot plants because he likes the way they look? If he tells a Colorado gun dealer that he grows pot when he tries to buy a gun, and gets denied a purchase for the same reason as the woman in Nevada, how might the 10th Circuit rule on that one?

Gard suspects such a case could have a different result because it could be a “cleaner” case. And if that happens, Supreme Court here we come. It should be noted that Congress could also step in, make marijuana legal at the federal level, and these issues would be moot. It also should be noted that’s not likely to happen anytime soon.

In Colorado, there isn’t a concerted coalition effort to lobby for law changes among proponents of legal cannabis and the Second Amendment community, say those who work in the industry.

“We don’t really get involved in the issue because it’s not really primary to our members,” says Taylor West, spokeswoman for the National Cannabis Industry Association, which has an office in Denver.

But, she said, “I think if a patient is legally accessing marijuana as medicine under state law then there’s no reason that should affect their constitutional right to possess a gun.”

The woman who brought the lawsuit in Nevada says she got a medical marijuana card in part to express her support for marijuana legalization, ABC News reported, but the court in its 3-0 decision said it was “reasonable for federal regulators to assume a medical marijuana card holder was more likely to use the drug.”

So, to recap: Can you lawfully have a gun in Colorado— say, a shotgun passed down to you by your uncle— and also be in possession of marijuana at the same time?

The answer depends upon whom you ask. Or, more importantly, who catches you doing it.