Say you smoke pot. And you’re flying from Logan to LA or Las Vegas or Nantucket — all places where recreational marijuana is legal. And, just hypothetically of course, you’ve got some weed and want to take it with you on your flight.
The confounding, Kafka-esque answer— made possible last fall, when Massachusetts voters legalized marijuana — is a hazy maybe.
Start with the basics: Marijuana possession is forbidden under federal law. So taking pot across state lines — or into federal airspace — is risky.
But possessing an ounce or less is legal in Massachusetts, and the Massachusetts Port Authority, which owns and operates Logan International Airport, doesn’t have any policy prohibiting it, so you can bring your stash onto airport property. The Transportation Security Administration isn’t looking for it, so you might glide through security.
But since the TSA is a federal agency that abides by federal law, if agents find some weed in your bag, they’ll refer you to the Massachusetts State Police.
Here’s the twist: When the trooper ambles over and determines you’re 21 or older and your baggie is an ounce or less, you’ll be let go in peace with your pipe and marijuana, said State Police spokesman David Procopio, because you wouldn’t be breaking state law.
So then you’re back with TSA agents. Will they confiscate your stuff?
“We would not retain drugs in the same way we wouldn’t retain fraudulent IDs or credit cards — we would kick those over to law enforcement,” said Mike McCarthy, a Boston-based spokesman for the TSA. “Our agents do administrative searches, not criminal searches.”
“I’d have to leave it at what I told you before,” McCarthy said. “Our officers are looking for any item that could cause catastrophic harm to the aircraft . . . but, as part of their duties, if they detect anything that they believe to be illegal, they will refer the passenger and the baggage over to local law enforcement, and it is up to local law enforcement how to respond.”
But, McCarthy said, TSA personnel would be unlikely to prohibit passengers from boarding their plane with marijuana a trooper has determined is legal.
“I don’t imagine anyone will not make their flight — but that’s up to local law enforcement, in this case, the State Police,” he said.
Is there a real-life example of pot at Logan?
In an e-mail, Procopio said troopers “responded to a call at one of the bag rooms at the request of TSA for a small amount of marijuana in a checked bag. Responding trooper determined the amount was less than an ounce and allowed the TSA to handle the issue.”
So what happened to that weed? McCarthy said he wasn’t aware of the incident.
Massport, an independent public authority that owns and manages Logan, doesn’t have a specific policy prohibiting or allowing marijuana, which has been legal in Massachusetts since Dec. 15.
“We abide by the decisions of the Massachusetts State Police and TSA. We haven’t ruled out developing a policy of our own in the future,” spokeswoman Jennifer B. Mehigan said in a statement.
The air travel gray zone is one of several created by the state’s new marijuana law. For example, Massachusetts now allows adults to grow, buy, possess, transport, and use limited amounts of marijuana. But selling it remains illegal until licensed stores are up and running — expected no earlier than the middle of 2018.
At least one aspect of traveling with marijuana remains clear: It’s definitely illegal to take marijuana to a state where the drug remains forbidden. So no flying with recreational marijuana to Orlando, where pot is illegal.
But flying into LAX in sunny Los Angeles? Pot’s no problem at California’s biggest international airport.
If Los Angeles Airport Police officers find an adult traveler flying in with an ounce or less of weed, said police spokesman Rob Pedregon, they will let the traveler go, because there is no violation of California law.
For fliers leaving the state, if the TSA finds marijuana and calls the airport police, Pedregon said, the same test applies: If the traveler is 21 or older and has an ounce or less, officers will let the person go with their marijuana.
“We don’t have the power to enforce the federal law,” he said.
Voters in Colorado, Oregon, Washington state, Alaska, Nevada, Maine, Massachusetts, California, and the District of Columbia have legalized recreational marijuana.
But some states where voters have passed legalization measures have instituted specific restrictions on air travel. Even though marijuana is legal in Colorado, for instance, you can’t fly into (or out of) Denver International Airport with it, because Denver forbids having marijuana on airport property.
But what about a flight from Boston to Martha’s Vineyard, Nantucket, or the Cape?
It’s a little hazy.
Does Cape Air, which during peak summer months averages more than 100 flights a day from Boston to the Cape and Islands, have a policy on pot?
“We can’t offer info at this time,” said spokeswoman Trish Lorino via e-mail.
Pro-pot lawyers say there’s an inevitable tension between state and federal law.
“Any time you have dual sovereignty with the state and federal government, you have a potential for murk,” said Michael D. Cutler, an attorney with expertise in marijuana law who helped write the ballot question in Massachusetts. “But this much is clear: a series of [Supreme Court] decisions have made clear the feds cannot commandeer state law enforcement to enforce federal law. So the question is: Will federal law enforcement come in to enforce federal law?”
Mark J. Connot, a Nevada lawyer with expertise in airspace and cannabis law, said the federal government is unlikely to expend any resources going after someone with a modest amount of weed. “Technically, is it a violation? Yeah,” he said. “Practically, are the resources going to be spent to get someone with an ounce or less? Probably not.”
A regional spokesman for the federal Drug Enforcement Administration did not respond to several messages.
A spokesman for the Federal Air Marshal Service, which is part of the TSA, said marshals’ primary mission is to detect, deter, and defeat acts of terrorism aboard aircraft. If they saw a passenger carrying marijuana, they would refer it to local law enforcement.
What about the FBI? It remains focused on large criminal enterprises and, law enforcement insiders say, hasn’t dealt with passengers with small amounts of marijuana at Logan in the recent past.
But there’s a twist. A spokesman for the Federal Aviation Administration pointed the Globe to federal aviation regulations that prohibit the operation of a civil aircraft within the United States with knowledge that pot is being carried on the plane.
Who would investigate a pilot or airline for an alleged infraction? The FAA, said spokesman Jim Peters.
Marijuana proponents hope the complexity fades away.
Lawyer John Swomley, a longtime prolegalization advocate, affirmed the law is currently unclear. But for adults possessing an ounce or less and getting on a plane from one place where marijuana is legal to another place where it’s legal, “I would hope that cooler heads would prevail and this becomes a nonissue.”Joshua Miller can be reached at email@example.com. Follow him on Twitter @jm_bos and subscribe to his weekday e-mail update on politics at bostonglobe.com/