The Supreme Court handed a major defeat to state medical marijuana laws this week, but pro-pot advocates said a little-noticed lawsuit wending its way through the courts might yet make legal pot a reality.

The suit hinges on a Food and Drug Administration regulation that says the agency can't approve marijuana – or any other substance – as a medicine unless research shows it's safe. But the government, which controls the only legal crop in the country, won't give scientists any marijuana to test, according to researchers who want to perform safety studies.

The impasse led to a lawsuit in July 2004 pitting the Multidisciplinary Association for Psychedelic Studies, or MAPS, against the Drug Enforcement Agency as well as the Department of Health and Human Services and the National Institute on Drug Abuse, or NIDA, for obstructing medical marijuana research.

"The energy in the legal arena is now going to shift to our effort to break the monopoly on supply," said Rick Doblin, founder and president of MAPS. "Now that (law enforcement) can go after high-profile targets, the only safety for patients is going to be to have it available through the FDA."

NIDA refused to comment on the lawsuit because the agency addresses abuse of marijuana rather than its medical uses, a spokeswoman said. But since the agency is the gatekeeper to the only legal source of the drug from a small farm at the University of Mississippi, researchers who want to study the drug's medicinal qualities have no choice but to query NIDA.

Doblin said the government pot is not only scarce but also low-quality. Patients have to smoke up to four times more than they would if they bought it on the street or in a buyers' club, and it's full of sticks and seeds.

After several years of rejections and revised protocols, Dr. Donald Abrams, now chief of hematology and oncology at San Francisco General Hospital, managed to gain NIDA's permission in 1997 to perform a study testing marijuana in AIDS patients. It found that the patients' viral load did not increase while smoking the drug.

Abrams recently completed a second study on 16 AIDS patients with painful nerve damage in their hands and feet. Preliminary results suggest that marijuana eased their pain, he said.

"I'm trying to generate some data so we can have some real evidence in this discussion," said Abrams, who is awaiting approval for one more study that if approved will examine the interaction between cannabis and opioids in cancer patients with persistent pain.

Doblin thinks the government is purposely setting up roadblocks to make it impossible to get enough data for FDA approval. Abrams' studies have involved 62 and 16 patients respectively – far too few to garner FDA approval – and Doblin said government agencies know that Abrams doesn't have the resources to perform a larger trial.

MAPS is also suing NIDA for ignoring its 2003 application to buy 10 grams of marijuana – a small amount worth no more than $100 – for a study that would examine the chemical makeup of vaporized marijuana, which it believes could be an alternative delivery method. The test would not involve human subjects.

"Supposedly that's what everyone wants – that this issue should be solved through science rather than through politics and that's what we're saying as well," Doblin said. "The problem is, when we try to do the science we find out the government is not really that interested in solving the issue through science."

The first hearing regarding the DEA suit is scheduled for late August.