One day after the midterm elections, U.S. Attorney General Jeff Sessions resigned at the request of President Trump. Sessions' exit could help propel pro-pot policy in Washington, D.C., as he was one of marijuana supporters' most vocal adversaries.

An obstacle to reversing marijuana prohibition

There are 33 U.S. states that have passed laws legalizing cannabis in one form or another, including three states in which voters cast ballots in favor of legalization on Nov. 6.

A marijuana leaf on a green background.

IMAGE SOURCE: GETTY IMAGES.

Even though a majority of U.S. states now have laws on the books that OK marijuana for medical use and 10 states have laws allowing marijuana's recreational use, marijuana is still a Schedule I controlled substance that's illegal at the federal level. As a result, the U.S. marijuana market is crimped by inadequate access to banking services and onerous tax treatment.

Sessions isn't the only reason there's been little progress toward marijuana legalization in Washington, D.C., but he's certainty an been an important one since Trump appointed him in 2016. As attorney general, Sessions, who has a long history of making anti-marijuana comments, controlled the Department of Justice, the Federal Bureau of Investigation, and the Drug Enforcement Agency (DEA) -- agencies tasked with enforcing marijuana's prohibition.

In 2016, the DEA considered changing marijuana's drug scheduling, but following discussions with the Food and Drug Administration, the DEA decided to leave marijuana's scheduling unchanged, citing a lack of scientific proof backing up claims of marijuana's medicinal benefits. Because marijuana's Schedule I status remained, the door has been left open for the federal government to enforce federal anti-marijuana rules even in states that have passed pro-pot laws.

The risk of federal action on marijuana nationwide has, until now, been heightened by Sessions' role in the administration. He had applauded President Reagan's War on Drugs. He had said that "we need grownups in Washington to say marijuana is not the kind of thing that ought to be legalized," and that "good people don't smoke marijuana."

Last year, he lobbied against policies preventing the Justice Department from going after cannabis companies that are operating legally in states that have passed marijuana laws. Specifically, he took aim at the Rohrabacher-Blumenauer amendment prohibiting the use of federal funds to interfere with states' implementation of their own marijuana laws.

As part of that effort, he sent a letter to senior members of the Senate and House condemning a Ninth Circuit court ruling prohibiting his department from enforcing the Controlled Substances Act in cases where marijuana businesses are operating in compliance with state law. His letter said the ruling was "unwise" in a period of a "historic drug epidemic and potentially long-term uptick in violent crime." He also said studies show marijuana poses a significant health risk and that its use can reduce a person's IQ.

His anti-marijuana stance was further evidenced by his decision in January to abandon the Cole memorandum, issued under President Obama. The memorandum had directed U.S. attorneys to focus on eight areas of enforcement, including distribution to minors and interstate trafficking, rather than individual possession by adults in states that have passed marijuana laws.

The all-important question

Trump isn't marijuana's biggest advocate, but his comments during the 2016 campaign suggest he supports states' rights and medical marijuana. The big question following Sessions' departure is, whom will Trump appoint next? On Wednesday, he announced the interim appointment of Matthew G. Whitaker, who was formerly Sessions' chief of staff. As for a permanent replacement, Trump simply tweeted that "A permanent replacement will be nominated at a later date."

If he installs a more marijuana-friendly person in the top spot, that could provide an easier path toward changes in Washington that, at a minimum, might make it easier to do business in pro-pot states and, at a maximum, allow for meaningful change in how marijuana is viewed at the federal level. 

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