Not everyone is happy about the fact that marijuana seems to be on an unstoppable track to nationwide legalisation. And yet with the House of Representatives passing a landmark bill just last week to decriminalise the drug across all states, it looks like that’s the future for America. The pushback lies in the fear that marijuana could cause all manner of health problems, from schizophrenia to respiratory issues. Alex Berenson of The New York Times warns that, “The wave toward legalisation ignores the serious health risks of marijuana.” Even the executive director of Pennsylvania Chiefs of Police Association expressed, “I would like to express my concerns, and those of many of our membership, about the legalisation of marijuana and the relative effects on public safety in those communities.”
To some people, the fact that marijuana has negative health effects alone should be enough to warrant its illegality, manifesting in a staunch national campaign against the baleful weed. To see the fallacy in this case, you don’t need to argue that these health concerns aren’t scientifically merited; instead, all you have to do is recognise that their existence isn’t enough to prove that marijuana should stay illegal—and why they actually support the case for legalisation. To the minds of elected officials, it might seem like a paradox that legalising marijuana would decrease the amount of people suffering from marijuana-related health problems. And yet that’s the situation we’re in.
One of the main arguments against the legalisation of cannabis is its correlation with psychosis: some researchers have estimated that people who use high-strength cannabis daily are five times more likely to have their first episode. When opponents of marijuana legalisation argue that the drug has been linked to a greater risk of mental health problems, it’s crucial to understand the components of the substance. Marijuana contains the active ingredients CBD, or cannabidiol, and THC, short for tetrahydrocannabinol. It’s the THC in marijuana that’s been linked to psychosis; and it was the potency of the strain, controlled by THC's concentration, that determined the extent of the risk. There’s evidence that CBD, on the other hand, can counter this effect. THC can also activate stress in the user, while CBD is well-determined to induce relaxation and counteract anxiety, leading to its use in various CBD oils. And thirdly, the dangers of addiction from marijuana stem from the presence of THC—the active ingredient with addictive properties. Safe to say, if the ingredients of marijuana were in a family, the problem child would be THC.
But the possible damaging effects of this ingredient cannot thrive in a vacuum. It needs a vessel to carry it, and that happens to be the five-leaflet plant of the cannabis family. The federal government’s response was criminalisation, in the now infamous ‘War on Drugs’. By all metrics, this method cataclysmically failed. When you legislate away a substance with high demand, you don’t get rid of that substance: you push it to an illegitimate market. So long as there’s money to be made by selling something that a lot of people want, a steady supply will find its way into the country, and the result is the thriving black market that populates the drug scene today.
The reason why potential drug users aren’t thrown off by the threat of prison is simple: it’s certainty of capture, and not just severity of punishment, that drives human decision making. Given that watching illegally downloaded movies currently carries as much as five years in prison and a £5000 fine, you might expect rates of movie copyright infringement to trail the floor; and yet people still illegally download movies all the time, without ever pausing to stop to consider the threat of the law. It’s because as high as the punishment is, they most likely won’t be caught. The same can be said for marijuana, where incarceration rates are incredibly low.
Because of this, the legality of drugs has very little significant impact on usage rates, and the statistics confirm this: youth marijuana use actually decreased in states when it was legalised. And when Canada legalised cannabis, daily or almost daily use stayed the same, while sparse use (having used it at least once over three months) only increased from 14.9% to 16.8%.
Now imagine that you’re a marijuana dealer. You’re growing your marijuana plants to have the precise combination of THC and CBD that you want, using artificial selection. You also know that out of all the active ingredients of marijuana, THC is both the one that gets the user high, and the one that controls how addictive it is. What are you going to do? You’re going to respond by artificially breeding your plants to have higher levels of THC, because it gets your client more bang for their buck—making them come back for more. And this is exactly the situation confirmed by the numbers. The average ratio of CBD to THC in marijuana has shifted from one to fourteen in 1995 to one to eighty in 2014, with the concentration of THC rising from 4% to 12% in that time.
So what would happen to the potency of marijuana if it became legal across all states? It would, for one, mean that marijuana could be sold in pharmacies and by recognised entities. The government would then gain access to regulate this marijuana and make sure that it passes certain standards for safety—meaning that less potent strains would be sold, with lower levels of THC, and higher levels of CBD. The outcome is that safer marijuana is now available to the public. Of course, this wouldn’t change the behaviour of all cannabis consumers. The makeup of marijuana users varies from addicts who will always crave the most potent strains possible, all the way to those just seeking an occasional high. Legalising marijuana would have no effect on addicts and serious users, who likely wouldn’t settle for anything less than ‘skunk’, an extremely potent strain which can have a THC concentration as high as 67%.
But for everyone else—who now has the choice between skunk from the streets and neatly packaged herbal cannabis—you can expect to see a positive shift towards lower-THC, safer marijuana, with higher concentrations of CBD to counter the risks. This would dramatically reduce the chance of users developing psychosis, addiction, and any of the other potential health problems linked to THC. And since we’ve already established that marijuana’s legal status doesn’t significantly impact how many people consume it, you’re left with a situation with a net decrease in health problems overall.
Not all policy effects are intuitive. You would hope that the people we elect, supposedly some of the most intelligent in the country, are capable of realising that obvious conclusions aren’t always true. Frantically banning potentially harmful substances like marijuana might be the go-to for some, but it relies on the embedded false assumption that banning drugs actually reduces their use—but instead, we’ve reached a climactic situation where drugs have become more potent, more addictive, and more dangerous behind back doors. It would be erroneous to claim that the legalisation of cannabis would solve all of the problems associated with its use; there is no one-policy solution to the the fact that some people will always want drugs, no matter the side effects. But by legalising cannabis, we can mitigate those harms for a great proportion of its users. It’s time for public officials to realise this and start listening to the data, not their intuition.