Last Thursday the House of Representatives resoundingly approved a spending rider that would bar the Justice Department from interfering with the implementation of state laws allowing the production, distribution, and consumption of marijuana for medical or recreational use. The amendment, a broader version of a rider that has protected state medical marijuana programs since 2014, was supported by 62 percent of the legislators who voted, including 41 Republicans as well as 226 Democrats.

"This is without a doubt the biggest victory for federal cannabis policy reform to date, and a hopeful sign that the harmful policies of marijuana prohibition will soon be a relic of the past," Aaron Smith, executive director of the National Cannabis Industry Association, said in a press release. "Interfering with successful, regulated cannabis programs is a tremendous waste of resources, and only serves to push the market back into the hands of criminals. The amendment approved today reflects a growing realization of these facts by lawmakers."

Amendment No. 17 to the Commerce, Justice, Science, and Related Agencies Appropriations Act of 2020, introduced by Rep. Earl Blumenauer (D-Ore.), says "none of the funds made available by this Act to the Department of Justice may be used" to "prevent" states from "implementing their own laws that authorize the use, distribution, possession, or cultivation of marijuana." It applies to the District of Columbia, the Northern Mariana Islands, Guam, Puerto Rico, and the U.S. Virgin Islands as well as the 47 states that have legalized some form of cannabis for medical or recreational use.

"I strongly urge that we build on the legacy that we have had in the past and that we move this forward to allow the federal government to start catching up with where the rest of the states are," Blumenauer said upon introducing the amendment. Del. Eleanor Holmes Norton (D-D.C.) spoke in favor of the amendment, saying, "The District has insisted that Congress cease interfering with our desire to commercialize adult-use marijuana, and I appreciate that D.C. is included with the other States that have the same goal."

Rep. Robert Aderholt (R-Ala.) spoke against the rider. "Under the Controlled Substances Act," he noted, "the Drug Enforcement Administration defines Schedule I drugs as having no current acceptable medical use and a high potential for abuse. According to the National Institute on Drug Abuse, there is no scientifically recognized medical benefit from smoking or eating marijuana plants. Claims of benefits from smoked or ingested marijuana are anecdotal and generally outright fabrications. It is established by fact that such marijuana use has real health and real social harms."

Rebutting Aderholt, Blumenauer argued that marijuana's Schedule I status cannot be rationally justified. "If we were rescheduling drugs today, cannabis probably wouldn't be scheduled at all," he said. "It is widely known now that there are, in fact, medicinal purposes to be obtained from using cannabis. That is why the voters in the gentleman's own state just approved medical marijuana. They are not goofy. They are not misled. They understand that there is compelling evidence, and any of us meeting with professionals can understand that. One of the reasons we don't have the research is because the federal government has interfered with [it]. But the evidence is clear. You can find that out with children in your state who use medical cannabis to stop extreme seizure disorders; people who use cannabis to be able to stop the violent nausea associated with chemotherapy; or veterans that use it for PTSD, traumatic brain injury, or chronic pain."

The 41 Republicans who sided with Blumenauer rather than Aderholt included freshman congressmen such as Kelly Armstrong (N.D.), Troy Balderson (Ohio), and Russ Fulcher (Idaho) as well as longtime marijuana reformers such as Justin Amash (Mich.), Thomas Massie (Ky.), Tom McClintock (Calif.), and Don Young (Alaska). They represent one-fifth of the Republicans who cast a vote.

We don't know yet whether Blumenauer's amendment will be part of the final appropriations bill approved by both houses of Congress. And unlike changes to the Controlled Substances Act, spending riders aimed at protecting state autonomy with respect to marijuana policy have to be renewed each year.

Last week's vote is nevertheless an important development, since it is the first time the House of Representatives has approved a broad form of marijuana federalism that encompasses general legalization as well as medical use. "Today's vote is the most significant step Congress has ever taken toward ending federal marijuana prohibition," said Steven Hawkins, executive director of the Marijuana Policy Project. "Congress is recognizing that the federal government must let the states decide on cannabis legalization—and not the other way around."