The federal government has a "responsibility" to facilitate sensible research into marijuana's medical benefits, Sen. Elizabeth Warren (D-Mass.) and seven other senators urged in a letter issued last week to multiple federal drug and health officials.
"While the federal government has emphasized research on the potential harms associated with the use of marijuana, there is still very limited research on the potential health benefits of marijuana -- despite the fact that millions of Americans are now eligible by state law to use the drug for medical purposes," the letter reads.
The senators praised the White House's recent lift of what was a mandatory bureaucratic review process, long criticized by researchers and lawmakers alike, that had stifled scientific research into the plant. But, they also encouraged the federal drug and health agencies to do more.
For patients in states with active medical marijuana programs, the senators recommend the agencies use their existing tools to collect national data, conduct surveillance and perform clinical trials.
"It is time for the federal government to pick up those tools and use them," the letter reads.
The senators also implored the agencies to collaborate and support "independent scientists" by eliminating needless federal barriers that stifle research into the plant.
To date, 23 states have legalized marijuana for medical purposes. Nearly 20 others have legalized the limited medical use of CBD, or cannabidiol, a compound found in the cannabis plant that doesn't produce the euphoric sensation associated with the drug but has shown medical promise. Still, the federal government continues to ban the plant.
Under the Controlled Substances Act, the U.S. has five categories for drugs and drug ingredients. Schedule I is reserved for drugs that the DEA considers to have the highest potential for abuse and no medical value. Marijuana has been classified as Schedule I for decades, alongside other substances like heroin and LSD.
Critics of federal policy say that the classification is due in part to a lack of cannabis science in the United States, stemming from a federal stranglehold on marijuana research. There's only one federally legal marijuana garden in the U.S., at the University of Mississippi. The National Institute on Drug Abuse oversees the operation, and it's the only source of marijuana for federally sanctioned studies on the drug.
Federal authorities have long been accused of funding marijuana research that focuses on the potential negative effects of the substance. The DEA has also been accused of not acting quickly enough when petitioned to reschedule marijuana, and for obstructing science around the drug.
Warren was joined by Democratic Sens. Jeffrey Merkley (Ore.), Ron Wyden (Ore.), Barbara Mikulski (Md.), Edward Markey (Mass.), Barbara Boxer (Calif.), Cory Booker (N.J.) and Kirsten Gillibrand (N.Y.) -- about half of whom are cosponsors of a sweeping bill introduced earlier this year designed to drastically reduce the federal government's ability to crack down on state-legal medical marijuana programs while also encouraging more research into the substance.
The letter, dated July 9, was addressed to the heads of the Department of Health and Human Services, the Office of National Drug Control Policy and the Drug Enforcement Administration. Officials from the Centers for Disease Control, the National Institutes of Health, the Food and Drug Administration and National Institute on Drug Abuse were also copied on the letter.
Officials from the Department of Health and Human Services, the Office of National Drug Control Policy and the Drug Enforcement Administration did not immediately respond to requests for comment.
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