Over the past few years, eight states and Washington, DC, have legalized marijuana for recreational purposes, and 20 more have legalized it for medical uses. President Barack Obama’s administration took a hands-off approach to these states, deciding not to enforce federal laws that prohibit marijuana use as long as states followed some rules.

But what will President Donald Trump’s administration do?

On Thursday, White House press secretary Sean Spicer gave the clearest answer yet to this question:

There’s two distinct issues here: medical marijuana and recreational marijuana. I think medical marijuana, I’ve said before, that the president understands the pain and suffering that many people go through, who are facing especially terminal diseases, and the comfort that some of these drugs, including medical marijuana, can bring to them. And that’s one that Congress, through a rider in [2014], put an appropriations bill saying that the Department of Justice wouldn’t be funded to go after those folks. There’s a big difference between that and recreational marijuana. And I think that when you see something like the opioid addiction crisis blossoming in so many states around this country, the last thing we should be doing is encouraging people. There’s still a federal law that we need to abide by when it comes to recreational marijuana and other drugs of that nature.

Given all this, Spicer said, “I do believe that you’ll see greater enforcement of it.” (For the record, though, the research increasingly shows that relaxing marijuana laws leads to fewer opioid overdose deaths.)

Under the Controlled Substances Act, marijuana is considered a Schedule 1 drug. This classification is the strictest category for any drug, and it means that the federal government denies pot has any medical value, and bans it for both recreational and medical uses.

But it’s true that, as Spicer said, Congress passed a budget rider that stops the Justice Department from spending money to crack down on medical pot laws. So the DOJ can’t use resources to go after states’ medical marijuana laws, but it can use resources to try to block recreational marijuana laws.

Still, it’s hard to gauge just how seriously anyone should take Spicer’s comments here. The Trump administration has been all over the place on this issue: Trump said that it “should be a state issue, state by state,” which is essentially how Obama handled it. But Attorney General Jeff Sessions, who as head of the Department of Justice is in charge of enforcing federal laws, as a senator previously said that “good people don’t smoke marijuana” and urged the Obama administration to take enforcement more seriously.

It’s also unclear what stricter enforcement could mean. Will federal authorities raid pot shops that are considered legal under state laws? Will they arrest individual marijuana users? Will they just do more to enforce some of the rules laid out by the Obama administration, like preventing legal pot from ending up in kids’ hands or across state borders? We don’t know. (The Trump administration didn’t respond to requests for clarification.)

What is clear, though, is that any crackdown would be very unpopular. A poll released on Thursday by Quinnipiac University found that 59 percent of US voters support marijuana legalization, and that 71 percent said the federal government should not crack down on states with marijuana legalization laws. (Other surveys, including by Vox and Morning Consult, have found majority support for pot legalization.)

So if the Trump administration does decide to go after marijuana, it could potentially expect some big public backlash.

Watch: How medical marijuana could help combat the opioid painkiller and heroin epidemic