The medical marijuana advocacy group Americans for Safe Access (ASA) and the Coalition for Rescheduling Cannabis (CRC) on Thursday appealed the federal government's decision to keep marijuana classified as a dangerous drug with no medicinal value.

The Drug Enforcement Administration denied a nine-year-old petition to initiate proceedings to reschedule marijuana in late June, claiming that, "marijuana has a high potential for abuse, has no accepted medical use in the United States, and lacks an acceptable level of safety for use even under medical supervision." The decision (PDF) was announced two weeks ago.

The petition sought to have marijuana removed from schedule I of the federal Controlled Substances Act and rescheduled in schedule III, IV or V. Currently, the DEA classifies marijuana as a schedule I drug: the most restrictive classification reserved for street drugs like heroin with a high potential for abuse and no real medicinal value.

"By ignoring the wealth of scientific evidence that clearly shows the therapeutic value of marijuana, the Obama Administration is playing politics at the expense of sick and dying Americans," said ASA Chief Counsel Joe Elford, who filed the notice of appeal today (PDF).

"For the first time in more than 15 years we will be able to present evidence in court to challenge the government's flawed position on medical marijuana."

The use of medical marijuana has been legalized in 16 states and the District of Columbia. But, according to the DEA, marijuana cannot be considered to have medicinal value because there is a lack of scientific studies assessing its safety and efficacy as a medicine, and the scientific evidence is not widely available. The agency also noted there are no U.S. Food and Drug Administration (FDA)-approved marijuana products at present.

Although hundreds of studies have found marijuana has medical value, its status as a schedule I substance has prevented clinical studies, like those conducted on pharmaceutical drugs, from taking place in the U.S.

Just days after the DEA insisted that there is no medical value to marijuana, the White House appeared to contradict the position, saying in a report that there may actually be "some" medical value to "individual components of the cannabis plant."

The statement was just a small part of the Office on National Drug Control Policy's yearly update on the progress of the drug war and its goals moving forward. Overall, the document only serves to affirm the federal prohibition of marijuana and what it calls "'medical' marijuana," which it still views as illegitimate.

The American Medical Association, the largest physician's organization in the U.S., adopted a resolution in 2009 calling on the DEA to reclassify marijuana to faciliate research on marijuana-based medicines.

"Results of short term controlled trials indicate that smoked cannabis reduces neuropathic pain, improves appetite and caloric intake especially in patients with reduced muscle mass, and may relieve spasticity and pain in patients with multiple sclerosis," the AMA's resolution (PDF) reads.

"The future of cannabinoid-based medicine lies in the rapidly evolving field of botanical drug substance development, as well as the design of molecules that target various aspects of the endocannabinoid system," the resolution continued. "To the extent that rescheduling marijuana out of Schedule I will benefit this effort, such a move can be supported."

Americans for Safe Access argues that by failing to reclassify marijuana, the federal government has stifled meaningful research into a wide array of therapeutic uses that could benefit patients.

"With science on our side, we will put an end to the government's political posturing," Elford said, "and force the Obama Administration to adhere to its own stated policy of emphasizing science over politics."

An ABC News poll found last year that eight in 10 Americans favor legalizing medical marijuana.

With prior reporting by Stephen C. Webster