WASHINGTON — As scientists try to research the medical benefits of marijuana, a simple problem has emerged: How do you research marijuana if no one can produce it under federal law?

Despite a solution proposed in mid-2016, which allowed the Drug Enforcement Administration to approve marijuana manufacturers, only the University of Mississippi has been approved, despite dozens of applications. And there’s no sign the DEA intends to approve others anytime soon.

Advocates seem to blame one person for the delays: Attorney General Jeff Sessions.

“The holdup is the Department of Justice,” said Rep. Matt Gaetz, R-Fla.

Congress is trying to take action to get the process moving.

A House committee recently approved a bipartisan bill authored by Rep. Luis Correa, D-Calif. It pushes the Department of Veterans Affairs to research marijuana’s ability to treat post-traumatic stress disorder and other chronic pain.

Even in places where medical or recreational marijuana is legal at the state level, the VA has to comply with federal law and therefore cannot prescribe cannabis for medical purposes. If the bill can pass Congress, increasing future demand on medical marijuana research and the limitations of only having one manufacturer could severely limit research capabilities.

Jeff Sessions

An official for the National Institute on Drug Abuse, which works with the University of Mississippi, said inventory is “more than sufficient” for current needs. And while the agency said there hasn’t been a major increase in demand in recent years, there has been “emerging interest from the research community for a wider variety of marijuana and marijuana products.”

There were 354 individuals and institutions approved by the DEA to conduct research on marijuana and its related components as of Aug. 11, 2016, the most recent data available. The University of Mississippi is the only manufacturer available to legally produce marijuana for those researchers.

The university can produce over 500 kilograms of marijuana in an outdoor growing season, and about 10 kilograms during indoor seasons, according to the university website.