Scott Pruitt 's confirmation last week to lead the Environmental Protection Agency puts a second voice in President Trump's cabinet who has taken a strong stance against the growing trend of liberalization of marijuana laws across the country.

Pruitt won't interface with marijuana policy in his day-to-day work as EPA chief. But for those who invest in the Beltway theory of "the last person to talk to Trump wins," Pruitt could be a weighty ally if called upon by the administration's toughest opponent of pot legalization, Attorney General Jeff Sessions.

While attorney general of Oklahoma, Pruitt sued Colorado over the state's decriminalization of marijuana. The suit alleged that Colorado's marijuana industry harmed neighboring states by "draining their treasuries, and placing stress on their criminal justice systems."

The U.S. Supreme Court declined to hear the case.

Pruitt was also at the center of a spat over a 2016 Oklahoma ballot initiative that aimed to legalize medical marijuana. Backers of the initiative sued him, arguing the ballot title he submitted, which significantly changed the original title, would mislead voters into thinking they were voting on full legalization, not legalization that was restricted to medical use. The legal fight pushed the vote to the 2018 ballot.

John Hudak is a senior policy analyst with the liberal think tank Brookings Institution in D.C., and author of the book, "Marijuana: A Short History." He said it is unclear whether the Trump administration has time at all to look at legalized pot given its numerous other agenda items, but the addition of Pruitt to the cabinet at least puts the elements of a strong, anti-pot coalition in place.

"I think within any administration, you have camps that set up, that can help reinforce unrelated policy areas," Hudak said. "With no clear experts on drug policy in the administration, "you might have someone step in from another agency and say, 'Hey listen, I handled this when I was attorney general of Oklahoma. Let me know what I can do.'"