Trump Today: Press secretary warns of more pot enforcement

White House Press Secretary Sean Spicer said that states should expect to see “greater enforcement” of federal laws against marijuana use under the Trump administration’s Justice Department.

Addressing reporters at a press conference Thursday, Spicer suggested that the administration and Attorney General Jeff Sessions would be taking a particularly hard look at states that have legalized marijuana for recreational use. Those include California, where sales of marijuana for recreational use are set to start next year.

On the campaign trail, Trump said that he supported marijuana for medical use, but on Thursday, Spicer said there was a “big difference” between the use of the drug for medicinal versus recreational purposes.

Spicer went on to reference the opioid addiction crisis gripping much of the nation, saying that “the last thing we should be doing is encouraging people. There is still a federal law we need to abide by in terms of when it comes to recreational marijuana,” Spicer said, according to a Forbes report on the press conference.

WASHINGTON, DC - FEBRUARY 23: White House Press Secretary Sean Spicer holds the daily briefing February 23, 2017 in at the White House in Washington, DC. Spicer addressed U.S. President Donald Trump's recent action on transgender bathroom in public schools. (Photo by Aaron P. Bernstein/Getty Images) less WASHINGTON, DC - FEBRUARY 23: White House Press Secretary Sean Spicer holds the daily briefing February 23, 2017 in at the White House in Washington, DC. Spicer addressed U.S. President Donald Trump's recent ... more Photo: Aaron P. Bernstein, Getty Images Photo: Aaron P. Bernstein, Getty Images Image 1 of / 15 Caption Close Trump Today: Press secretary warns of more pot enforcement 1 / 15 Back to Gallery

What we know:

Sessions has been a staunch opponent of marijuana legalization in the past, prompting concern from cannabis advocates over how the administration would treat the growing number of states who have moved toward legalization or decriminalization in recent years. California voted to legalize marijuana in 2016.

“The vast majority of Americans agree that the federal government has no business interfering in state marijuana laws,” said Mason Tvert, the communications director for the Marijuana Policy Project, in a statement following the press conference on Thursday.

“This administration is claiming that it values states’ rights, so we hope they will respect the rights of states to determine their own marijuana policies. Mr. Spicer says there is a difference between medical and recreational marijuana, but the benefits of and need for regulation apply equally to both,” Tvert said.

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Marijuana is still illegal under federal law. The Obama administration took a hands-off approach to states’ efforts to legalize the drug. The Justice Department is still prohibited from using federal funds to interfere with states’ ability to implement medical marijuana laws.

What we don’t know:

We don’t know what the promised enforcement will look like.

Congress could change the prohibition on using federal funds for marijuana enforcement when it passes the next federal budget.

States could fight efforts to weaken their marijuana laws in court.

Dominic Fracassa is a San Francisco Chronicle staff writer. Email: dfracassa@sfchronicle.com Twitter: @dominicfracassa