Pot legalization opponents exaggerate dangers

The United States is in the midst of a marijuana revolution: There has been a steady, uninterrupted trend toward decriminalization and outright legalization. According to a guide on Governing magazine’s website, 33 states have legalized at least some form of marijuana use, including 10 in which recreational use is no longer prohibited. In New York, state lawmakers are working on a legalization bill they hope to pass by the end of the legislative session, which would allow it to edge out neighbor New Jersey to be the 11th.

It shouldn’t come as a surprise that this rapidly liberalizing legal landscape has stoked certain longstanding fears about the risks of using cannabis. In New York, legalization opponents argue pot is more harmful than advocates admit, or that it serves as a gateway to harder drugs. “There are huge dangers,” said Ed Cox, who recently stepped down as the state’s Republican Party chairman.

Overall, the portrait opponents paint is an exaggerated caricature of marijuana’s effects. But it’s important to examine the claims one by one, because some have more merit than others. They individually range from “completely unsupported, based on the available evidence” to “plausible, but in need of more research.”

And, as this conversation unfolds, it’s vital to not lose sight of the broader context: The key question isn’t just whether pot might, in some circumstances, cause harm, but whether it causes enough harm to justify the enormous cost, in both dollars spent on and lives ruined by overzealous law enforcement, of government efforts to criminalize it, especially given that a substance that appears to be far more dangerous – alcohol – is legal.

At the national level, a book published earlier this year called “Tell Your Children: The Truth About Marijuana, Mental Illness, and Violence”by Alex Berenson, a former New York Times reporter, claimed that pot use – and legalization – is linked to both serious mental health problems and violence. In an accompanying Times column, he wrote that “the first four states to legalize – Alaska, Colorado, Oregon and Washington – have seen sharp increases in murders and aggravated assaults since 2014, according to reports from the Federal Bureau of Investigation.”

The evidence for a pot decriminalization-violence link is quite weak, and the evidence for a pot consumption-violence link is totally nonexistent – possibly even backward. Berenson picked a period of time during which there was a nationwide increase in murders, meaning it’s shaky to finger pot as the causal culprit. And there wasn’t a sudden uptick in all the states in question, anyway. In Washington, for example, there was a bit of a zigzag pattern to the murder rate that doesn’t quite fit Berenson’s narrative.

And when it comes to increased pot consumption – the mechanism by which legalization supposedly increases violent crime – weed smoking has gone up while violent crime has gone down. As Mark Kleiman, a drug-policy expert at New York University, pointed out to me when I first wrote about Berenson’s claims for New York magazine in January, “Cannabis consumption, and especially heavy cannabis consumption, has been on the rise since 1992,” while “over that period, national homicide rates have fallen more than 50%.” Clearly, pot use isn’t much of a risk factor when it comes to violent crime rates. (Whether or not increased pot use may actually reduce violent crime is another matter: While the drug causes relaxation in many users, and the correlation between rising consumption and dropping crime rates is suggestive, crime rates are driven by a complex web of conditions.)

Besides murder, prohibitionists have claimed expanded marijuana access is linked to all sorts of other problems. Julie Killian, a Republican politician in Westchester County and a co-founder of RyeACT, an anti-drug coalition in Rye that receives federal funding, said at a state budget meeting (as reported by the The Rye Record), “Proponents of legalization are ignoring the proven science, the experiences of other states, the environmental impacts, and the advice of doctors, first responders, and substance abuse professionals.” In the conservative City Journal, Steven Malanga wrote that “scientific journals report mounting evidence of the drug’s harmful psychological effects and social consequences. ... Most experts agree that mental illness and addiction, sometimes working in concert, are at the root of much of the problem. About half of all homeless people are thought to be addicted to drugs or alcohol, and 30 percent suffer from mental illnesses, including psychosis. As drug use has increased in America in recent years, homelessness has worsened, especially in places like Seattle and Portland, two cities in states that have legalized marijuana. Seattle’s homeless population, already among the nation’s largest, has been expanding considerably faster than the national average.”

Again, there’s an over-hyped assertion here that’s pretty easy to knock down: There’s just no data to suggest a causal relationship between marijuana and homelessness. Note that Malanga slips in “drugs or alcohol” rather than “marijuana” for that claim, lumping together all sorts of different subjects. Malanga is using a bait-and-switch, saying, in effect, that you shouldn’t legalize marijuana because other drugs and alcohol are bad for you.

It’s also an extremely dubious premise that getting pot in Seattle or Portland was especially difficult pre-legalization. And he’s ignoring other factors likely to have a far more profound impact on homelessness, from the bursting housing bubble and subsequent Great Recession to dramatically rising housing prices in hot West Coast real estate markets like, well, Seattle and Portland.

Moreover, the fact that homeless people are often addicted to drugs or alcohol doesn’t even tell us much about causality and its direction: Are they homeless because they use drugs or alcohol? Or do they use drugs or alcohol to cope with being homeless? Or are what social scientists call “omitted third variables” at play here? In other words, are people who have problems with money, or with functioning in society, or who suffer from mental illnesses, both more likely to be homeless and more likely to abuse drugs or alcohol?

When it comes to these more subtle, tricky-to-untangle claims about marijuana, there’s a lot we don’t know. As Malcolm Gladwell summed up a 2017 National Academy of Medicine report on the subject, “Does the use of cannabis increase the likelihood of fatal car accidents? Yes. By how much? Unclear. Does it affect motivation and cognition? Hard to say, but probably. Does it affect employment prospects? Probably. Will it impair academic achievement? Limited evidence.”

Part of the reason we know so little is that for a half-century the federal government has classified marijuana as a Schedule I drug – meaning it has “no currently accepted medical use and a high potential for abuse.” As Angela Chen noted in The Verge in November, “scientists who want to study the substance must use federally approved samples, which aren’t as potent as the offerings readily available to consumers. Though the agency has repeatedly refused to reschedule marijuana, two years ago, it did promise to give licenses to more universities to do marijuana research.” But that hasn’t really happened, she went on to note.

It is probably the case that for some people with preexisting mental health conditions or other stressors, smoking a lotof pot is a bad idea. It’s probably also not a great idea for young teenagers to smoke it heavily. (But the same thing can be said, with more confidence, about alcohol – and adults don’t get thrown in jail for possession of alcohol.) There are a lot of “probablys” because there’s such a vacuum of solid research.

Especially given the United States’ tremendously overzealous response to marijuana in the past, it’s important to fill that vacuum with common sense, the science we do have and future research – not with fear mongering.