President-elect Donald Trump’s decision to nominate Sen. Jeff Sessions to be the next attorney general has proponents of weed legalization freaking out, and for good reason.

Sessions, a staunch conservative with a troubling record on many issues important to progressives, from civil rights to immigration reform, has an especially unfriendly stance on marijuana.

Earlier this year during a Senate hearing about state marijuana laws, Sessions said “good people don’t smoke marijuana.” He also suggested that legalization would lead to more people using hard drugs, even though studies have repeatedly disproven the argument that weed is a so-called “gateway drug.”

“We need grown ups in Washington to say marijuana is not the kind of thing that ought to be legalized, it ought not to be minimized, that it is in fact a very real danger,” Sessions said. “You’ll see cocaine and heroin increase more than it would have, I think, had we not talked about it.”

During the same hearing, Sessions criticized President Obama for admitting to past marijuana use, saying “You can’t have the President of the United States of America talking about marijuana like it is no different than taking a drink.”

Sessions was denied a federal judge position in 1986 in part because of persistent allegations of racism, including one instance in which he joked that he was fine with the Ku Klux Klan “until I found out they smoked pot.”

And during Senate confirmation hearings last year for Attorney General Loretta Lynch, Sessions urged her to speak out against state-level legalization, saying vocal opposition by her predecessors “kept bad decisions from being made.”

His remarks appear starkly at odds with Trump’s own stated position on marijuana legalization, who, when asked about the issue during a campaign rally last October, said, “I really believe you should leave it up to the states.”

Four states — California, Nevada, Massachusetts, and Maine — voted to legalize recreational marijuana use by adults on Election Day this year, following previous moves by Colorado, Washington, Oregon, Alaska, and Washington, D.C. Including medical marijuana, 29 states now allow some form of legal weed. The drug remains illegal under federal law, but the Department of Justice has so far decided not to intervene in states where weed has been legalized.

Oregon Sen. Ron Wyden told VICE News on Friday that Trump’s decision to nominate Sessions means “there’s going to be some real confusion about what the administration’s position is” on marijuana.

“In a new administration, all it would take is one Justice Department memo for businesses that follow the law in their states to become targets of raids and prosecutions,” Wyden said. “This is a very relevant issue this afternoon here in the nation’s capital.”

Though Sessions still has to be confirmed by the Senate, if he becomes attorney general he will oversee the entire Department of Justice, including the Drug Enforcement Administration and federal prosecutors across the country. That’s a terrifying proposition for groups like the National Organization for the Reform of Marijuana Laws (NORML), which labeled Sessions an “anti-marijuana zealot” in a statement released on Friday.

NORML Executive Director Erik Altieri said the prospect of Sessions becoming attorney general “should send a chill down the spine of the majority of Americans who support marijuana law reform, and who respect the will of voters to enact regulatory alternatives to cannabis prohibition.”

Strong voter support for marijuana legalization, combined with opinion polls that show 60 percent of Americans now support ending pot prohibition, has some advocates hopeful that Trump will restrain Sessions from cracking down on states with legal weed.