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420, cannabis, illegality, and the cost of prohibition

By Mitch Earleywine


Cannabis became essentially illegal in the United States in 1937. Perhaps this 75 year experiment has provided enough data for some informed decisions. We’re up to over 800,000 arrests each year, with government spending billions annually on marijuana control. Yet more people have tried the plant than ever before. Several authors suggest that alternatives to prohibition might prove cheaper, send fewer people through our courts, and maintain respect for the law. It seems oddly un-American that a citizen can go to jail for owning a plant, especially here in the land of the free. But change is scary, and fear runs politics in frightening ways.

The experience of other humans might be relevant to our decisions about marijuana policy. Sure, no other country is like the good ole US of A, but most folks will agree that people are people. The Netherlands has had cannabis available for purchase for years. Teen use there is less than it is here, and users in Amsterdam are less likely to use hard drugs than those in San Francisco. Portugal quietly decriminalized possession in 2001. Teen use there has dropped. They also have the lowest rates of lifetime use in the European Union. But hey, these aren’t Americans. Data from the US come from nearly a dozen states that have decriminalized at one time or another. The change in laws had little impact on use. A citizen might wonder if any reasonable law has any impact on use at all. In fact, most people who have never used marijuana claim that they would have no interest in trying it even if it were legal.

So why have marijuana prohibition? It’s not quite clear. Many claim that prohibition developed to limit harm. You know, laws that will protect us from ourselves. Data from the last 5,000 years suggest that the harm is not dramatic. Respiratory symptoms associated with smoking are minimal in those who do not smoke cigarettes. The occasional coughing or wheezing associated with smoking the plant appears to diminish when users turn to the vaporizer — a gizmo that heats the plant without actually igniting it, forcing the cannabinoids off in a fine mist. Links between cannabis use and mental illness seem to arise only in subset of folks who begin extensive use early in life. And then only sometimes. Studies that fail to find any links to mental illness are hard to publish in the first place and rarely get any media attention. It’s unclear how seriously to take this research. Despite cries that marijuana will make folks psychotic, the rates of schizophrenia are pretty much the same across countries and eras with dramatically different laws.

Tales of amotivational syndrome and cannabis-induced violence have finally decreased dramatically. Yes, some of the lazy and some of the hostile smoke marijuana. But they were lazy or hostile before they used the plant. And markedly more lazy and hostile folks don’t use the plant at all. Laboratory experiments show that people who’ve used the plant recently are no more aggressive than those who smoked a placebo. In one experiment on amotivation, participants built chairs in the lab for money after smoking marijuana or a placebo. Instead of showing amotivation, they formed a union, demanded more money per chair, and then built them like crazy. Most serious academic journals won’t even publish papers on these topics anymore. The gateway theory — the intriguing idea that using marijuana will make someone suddenly desire hard drugs the same way that salt makes us thirsty — also has little actual support. Yes, many heroin users had marijuana first. Many also smoked cigarettes, rode rollercoasters, and neglected to wear seatbelts. Some people simply enjoy doing a lot of wild things. But few marijuana users have actually ever seen heroin, much less tried it.

The idea that prohibition is around to limit harm seems a bit odd when we think about all the potentially harmful things that are legal. Some states allow citizens to carry concealed semi-automatic weapons, rent a jet fighter, or own a grizzly bear. Sky diving, bungee jumping, and motorcycling also come to mind. More people have died from these activities than ever overdosed on marijuana. A few chemicals that alter consciousness also remain accepted despite established links to health problems. Caffeine, nicotine, and alcohol have documented effects on stroke and heart attack and some cancers. Their toxicity is much higher than marijuana’s. But as long as they are consumed in a way that causes no harm to others, they remain legal.

From a combination of economic incentives and a sense of justice, the world has slouched toward progress in appreciating diversity. People are starting to respect each other a little more, regardless of age, ethnicity, gender, occupation, sexual orientation, religion, political affiliation, or education. Many argue that this greater respect benefits everyone. We approach a point where people might tolerate others who think differently. Perhaps we could tolerate people who want to use marijuana without causing harm to themselves or others. Only time will tell.

Mitch Earleywine, Ph.D. is the author of Understanding Marijuana: A New Look at the Scientific Evidence and Pot Politics: Marijuana and the Costs of Prohibition. A Professor of Clinical Psychology at the University at Albany, State University of New York, he teaches drugs and human behavior, substance abuse treatment and clinical research methods. He has received 21 teaching commendations, including the coveted General Education Teaching Award from the University of Southern California and the Chancellor’s Award for Excellence in Teaching from the State University of New York system. His research funding has come from the National Institute on Alcohol Abuse and Alcoholism, the Alcoholic Beverage Medical Research Foundation, and the Marijuana Policy Project. He serves on the editorial boards of four psychology journals and has more than 100 publications on drug use and abuse. He is the only person to publish with both Oxford University and High Times.

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