The U.S. Drug Enforcement Administration lists marijuana in the most restrictive of five classes that the agency uses to regulate dangerous drugs. Marijuana is classified as a Schedule I substance, which is the ranking reserved for drugs with the greatest potential for abuse and with no medicinal value. Heroin, ecstasy and LSD are listed in that category, too, while cocaine and methamphetamine rank one level lower than marijuana, as Schedule II.

Almost since marijuana was first classified this way, advocates have been fighting to “reschedule” it to a lower tier. They argue that the Schedule I classification isn’t justified on scientific grounds. Marijuana is not considered highly addictive or dangerous except possibly for adolescents who smoke it while their brains are still forming. And the plant seems to hold medical promise in a number of areas -- one drug that is derived from a compound found in marijuana has already been approved to treat nausea in cancer patients.

The strict Schedule I label is problematic, advocates say, because it incurs the harshest federal penalties for those who are caught with it and adds bureaucratic hurdles for researchers who want study it. “I see dozens of cases a month that are impacted by this classification,” says Michael Cindrich, an attorney in San Diego, California, who specializes in criminal cases related to medical marijuana. Meanwhile, the significance of the designation has blurred following more states legalizing recreational marijuana and Congress ordering the Department of Justice to stop pursuing criminal cases against growers or users of medical marijuana.

A brief history of marijuana

So why is marijuana a Schedule I drug in the first place? It all dates back to 1970, when Congress passed the Controlled Substance Act, which was signed by President Richard Nixon. The act established the schedules by which drugs would be classified and temporarily listed marijuana as a Schedule I substance, subject to review. The administration then formed a commission to study marijuana and advise the administration on where it should be permanently placed. “When Nixon created the Controlled Substances Act in the '70s, he didn't really know where to place marijuana on the list of schedules,” says Kris Hermes, media specialist with an advocacy group called Americans for Safe Access.

Starting two years after the Controlled Substance Act, the National Commission on Marihuana and Drug Abuse issued a series of reports (read them here: report one, report two) on the state of marijuana in the U.S. The commission acknowledged that marijuana was less a serious threat to public health than a sensitive social issue and recommended changes to federal law that would permit citizens to possess a small amount of it at a time, while still maintaining that the drug should not be legalized.

The commission's approach to drug policy didn’t resonate with many Americans or politicians at that time, who were far more concerned about the potential societal ills that could strike if marijuana use was left unfettered -- an attitude that Cindrich says was partially based in racism. “At that time, the majority of marijuana users were black and Hispanic so it was a way for the U.S. government to keep tabs on the minorities that were living and working in the country,” he says.

The drug ultimately remained in the highest tier because of these fears, which were perhaps most evident at a senate hearing in 1974 with a subcommittee led by Sen. James Eastland, D-Miss. In his testimony, Eastland recalled a series of protests at University of California, Berkeley in the 1960s and warned, “If the cannabis epidemic continues to spread at the rate of the post-Berkeley period, we may find ourselves saddled with a large population of semi-zombies – of young people acutely afflicted by the amotivational syndrome.” Some say that the opposition of Eastland and his subcommittee quashed any chance that the drug would be downgraded to Schedule II or III. “It's all politics and then we got stuck in the ‘Just Say No’ era which lasted 20-some years,” says Paul Loney, an attorney in Oregon who specializes in marijuana legal issues.

Support for 'rescheduling'

Around the same time that the commission was issuing its report, a group known as the National Organization for the Reform of Marijuana Laws filed the first petition asking the DEA to place marijuana in a lower level of drugs. That petition was rejected in court after a 22-year battle. Another petition was brought forth in 2002 by the Coalition to Reschedule Cannabis, but was also declined by the DEA. An appeal of that decision was dismissed on the grounds that there was no sufficient medical use shown in phase two and three clinical trials for marijuana. Since then, the FDA has conducted two analyses of the status of marijuana for the DEA and suggested it remain a Schedule I drug, Bloomberg reports.

In order to change marijuana’s classification, today’s advocates can work through one of several routes. They could file another petition with the DEA, despite the repeated failures of the past. They could also hope for Congress to pass a bill similar to one that was introduced last year that would order a reclassification. Hermes says a new bill for this legislature is in the works and will be introduced in the coming months. “We're turning our attention to legislation in Congress since they've shown a willingness to grapple with this issue,” he says. Another option would be to hope President Obama takes executive action to reclassify the drug, though his administration has stated that it would prefer to wait for Congress to lead that effort.

Advocates say that pressure from a pending decision by a federal judge in California may help, if the judge rules that the penalties for marijuana offenses should be less harsh than those given for typical violations of a drug with Schedule I classification. A positive ruling for the medicinal marijuana growers in that case could sway other courts to change their tune toward the drug in the future, and put further pressure on the DEA to reexamine the drug’s classification. However, "That's a slow process," Loney says, "much slower than an agency review can be, which is much slower than the administration could come out to say ‘Hey, we're rescheduling this from a Schedule I to a Schedule II.'"