The spread of marijuana legalization, explained

by German Lopez

There are no documented deaths from a marijuana overdose, but that doesn't mean pot is harmless.

"The main risk of cannabis is losing control of your cannabis intake," Mark Kleiman, a drug policy expert at New York University's Marron Institute, said. "That's going to have consequences in terms of the amount of time you spend not fully functional. When that's hours per day times years, that's bad."

Jon Caulkins, a drug policy expert at Carnegie Mellon University, put it another way: "At some level, we know that spending more than half of your waking hours intoxicated for years and years on end is not increasing the likelihood that you'll win a Pulitzer Prize or discover the cure for cancer."

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The risk of misuse and addiction (known in medical circles as "cannabis use disorder") is compounded by the widespread perception that pot is harmless: Since many marijuana users believe what they're doing won't hurt them, they feel much more comfortable falling into a habit of constantly using the drug.

The most thorough review of the research yet, from the National Academies of Sciences, Engineering, and Medicine, found that pot poses a variety of possible downsides — including for respiratory problems if smoked, schizophrenia and psychosis, car crashes, general social achievement in life, and potentially babies in the womb.

But it doesn't seem to cause some issues that are typically linked to tobacco, particularly lung cancer and head and neck cancers. And the studies reviewed also suggest it carries several benefits, particularly for chronic pain, multiple sclerosis, and chemotherapy-induced nausea and vomiting. (There wasn't enough research to gauge if pot is truly good for some of the other ailments people say it's good for, such as epilepsy and irritable bowel syndrome.)

Critics of legalization claim that marijuana is a "gateway drug" that can lead people to try more dangerous drugs like cocaine and heroin, because there's a correlation between pot use and use of harder drugs. But researchers argue that this correlation may just indicate that people prone to all sorts of drug use only start with marijuana because it's the cheapest and most accessible of the illicit drugs. So if cocaine or heroin were cheaper and more accessible, there's a good chance people would start with those drugs first.

Overall, marijuana is a relatively safe drug — certainly less harmful than some of the drugs that are legal today, and potentially beneficial to some people's health through its medical use. But it's not harmless.

Given that marijuana's harms appear to be relatively small, though, advocates argue that, even if legalization leads to more pot use, it's worth the benefit of reducing incarceration and crippling violent drug cartels financed in part by revenue from illicit weed sales.

The research suggests marijuana legalization could lead to more use

In marijuana policy debates, whether legalization leads to more use is a crucial point of contention. Legalization advocates argue that allowing the drug but regulating it could reduce use and make its use safer, while critics say legalization will make pot more easily accessible and, therefore, more widely used and misused.

It's too early to say whether full legalization will lead to more widespread use, but recent research has found that pot use increased in states that legalized medical marijuana.

A comprehensive study from researchers at the RAND Corporation found that laws that allow medical marijuana dispensaries correlate with increases in overall pot use and dependence for adults 21 and older but only rises in dependence among youth. The findings suggest that allowing businesses to sell marijuana leads to more access and use, particularly for adults.

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Another study from Emory University researchers found that after some states legalized medical marijuana, they saw increases in overall marijuana use and, for adults 21 and over, a rise in binge drinking. The increase in binge drinking is particularly worrying because while marijuana carries few health and social risks, alcohol causes many serious public health and safety issues, such as liver damage, more fatal car crashes, and violent behaviors that can spur crime.

This latest research disputes earlier studies that found no increases in teen pot use following the legalization of medical marijuana. Drug policy experts argue these earlier studies were far less robust; they failed to control for factors like whether a state allows dispensaries, cultivation, or only possession — rendering them incapable of gauging the full effect of different pot policies.

Still, the studies by and large only show correlation, meaning it might not be medical marijuana legalization that's necessarily causing the increase in use. And it's possible — although not likely — that the effects of medical marijuana laws on use could be more pronounced than full legalization.

If legalization does lead to more pot use, the question for society and public health officials is whether that downside outweighs the benefits of legalization. More people getting intoxicated — albeit through a relatively safe drug — isn't an outcome that most supporters of legalization see as desirable, but banning pot has costs of its own, including hundreds of thousands of racially skewed arrests and the creation of a black market that helps finance violent drug cartels around the world.

The case for marijuana legalization

Supporters of legalization say prohibition has failed to significantly reduce access to and use of marijuana, while wasting billions of dollars and resulting in hundreds of thousands of racially skewed arrests each year. Legalization, by comparison, would allow people to use a relatively safe substance without the threat of arrest, and let all levels of government raise new revenues from pot sales and redirect resources to bigger needs.

A 2013 report by the American Civil Liberties Union found that there are several hundred thousand arrests for marijuana possession each year. These arrests are hugely skewed by race: Black and white Americans use marijuana at similar rates, but black people were 3.7 times more likely to be arrested than white Americans for marijuana possession in 2010.

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The arrests not only cost law enforcement time and money, they also damage the government's credibility. Former Washington, DC, Police Chief Cathy Lanier explained in early 2015, "All those arrests do is make people hate us. … Marijuana smokers are not going to attack and kill a cop. They just want to get a bag of chips and relax. Alcohol is a much bigger problem."

At the same time, prohibition has failed to notably reduce marijuana use. The war on drugs originally intended to take down the supply of illegal drugs, increase prices as a result, and make drugs unaffordable to users. Those goals by and large failed: The White House's Office of National Drug Control Policy found that marijuana prices dropped and stabilized after the early 1990s, and several surveys show marijuana use rose and stabilized among youth in the same time period.

Meanwhile, drug prohibition has created a lucrative black market for drug cartels and other criminal enterprises. Previous studies from the Mexican Institute of Competitiveness and the RAND Corporation suggested that marijuana at one point made up roughly 20 to 30 percent of drug cartels' revenue. Through legalization, drug cartels lose much of that revenue, as sales transition to a legal market, crippling resources these criminal groups use to carry out violent operations around the world.

Legalization would also allow the federal government to tax sales to fund new programs, including treatment for people with drug use disorders. A 2010 paper from the libertarian Cato Institute found legalizing marijuana would net all levels of the government $17.4 billion annually — half of that would come from reduced spending (particularly for drug enforcement), and the rest would come from taxing marijuana like alcohol and tobacco.

More broadly, the legalization movement falls into a broader shift against the harsh criminal justice policies that came out of the war on drugs. As Americans look for alternatives to punitive prison sentences that turned the US into the world's leader in incarceration, legalizing a relatively safe drug seems like low-hanging fruit.

The case against marijuana legalization

Opponents of legalization worry that fully allowing recreational marijuana use would make pot far too accessible and, as a result, expand its use and misuse.

The major concern is that letting for-profit businesses market and sell marijuana may lead them to market aggressively to heavy pot users, who may have a drug problem. This is similar to what's happened in the alcohol and tobacco industries, where companies make much of their profits from users with serious addiction issues. Among alcohol users, for instance, the top 10 percent of users consume, on average, more than 10 drinks each day.

Marijuana users exhibit similar patterns. In Colorado, one study of the state's legal pot market, conducted by the Marijuana Policy Group for the state's Department of Revenue, found the top 29.9 percent heaviest pot users in Colorado made up 87.1 percent of demand for the drug. For the marijuana industry, that makes the heaviest users the most lucrative customers.

Kevin Sabet, head of Smart Approaches to Marijuana, the nation's leading anti-legalization group, explained: "If we were a country with a history of being able to promote moderation in our consumer use of products, or promote responsible corporate advertising or no advertising, or if we had a history of being able to take taxes gained from a vice and redirect them into some positive areas, I might be less concerned about what I see happening in this country. But I think we have a horrible history of dealing with these kinds of things."

Drug policy experts say there are alternatives to commercial legalization, like putting state governments in charge of marijuana production and sales, which could tame the for-profit incentive and give states more direct control over prices and who buys pot.

But legalization opponents worry that any move toward legalization will inevitably attract powerful for-profit forces, especially since the marijuana industry has already taken off in several states.

"The reality is there are myriad other forces at work here," Sabet said. "Chief among them are the very powerful forces of greed and profit. When I look at how things are set up in states like Colorado, where the marijuana industry gets a seat at the table for every state decision on marijuana policy, it troubles me."

Given these concerns, opponents favor more limited reforms than legalization. Sabet, for example, said nonviolent marijuana users shouldn't be incarcerated for the drug. Other critics of legalization support legalizing marijuana for medical purposes but not recreational use.

It's rare that opponents of legalization argue for the full continuation of the current war on pot. SAM and its members, for instance, broadly agree that the current drug and criminal justice policies are far too punitive and costly, helping contribute to the mass incarceration of Americans. So while they may support some reforms, they feel that legalization simply goes too far — and could lead to worse consequences than the alternatives.

Uruguay is the first country to fully legalize marijuana

Outside of the US, Uruguay became the first country in the world to fully legalize marijuana in 2013. After Uruguay, Canada legalized marijuana in 2018.

Other countries haven't legalized, but they maintain relaxed approaches to marijuana use and sales.

The Netherlands allows citizens to keep and cultivate some marijuana, and police let coffee shops sell marijuana as long as they don't sell to minors, among other specific requirements. Spain also permits marijuana clubs where people can use the drug, although the drug is officially illegal to sell. And according to multiple reports from experts, visitors, and defectors, North Korea either has no law restricting marijuana or the law goes effectively unenforced.

One of the reasons marijuana legalization is so rare is because countries have been bound for decades by international treaties that established prohibition across the world. If a country tried to relax its marijuana laws, it could be seen as acting in violation of the treaties, which could lead to a loss in international standing and credibility.

But as more countries and their citizens view the war on drugs and marijuana prohibition in particular as failed policies, many are considering reform. In that sense, Uruguay — and soon Canada — could be the beginning of a much broader global movement.