Over the past ten years, 21 states and the District of Columbia have approved use of medical marijuana, and a new study out today through the National Bureau of Economic Research finds – shockingly – that the relaxation of medical marijuana laws leads to increased consumption of marijuana. Additionally and connected to this result, the authors report that relaxation of medical marijuana laws also lead to a rise in binge drinking among those of legal drinking age.

The problematic aspect here is that the increase in use of marijuana following medicinal laws also has led to an increase in abuse and dependency. As the authors write:

The effect of MML implementation on marijuana abuse/dependence constitutes a potential public health concern similar to that of prescription drug abuse/dependence (CDC, 2012): even if we assume that the increases in marijuana use we observed come from those who use the drug for validated medical purposes, there may still be possibility that marijuana abuse/dependence would increase as a result of MML implementation.

There’s a long line of argumentation when it comes to drug policy that “prohibition doesn’t work.” This depends on what it means to “work.” What is weird – and wrong – is the suggestion that prohibition does nothing to lower consumption. This new study provides evidence that yes, prohibition does lessen consumption. In this way, prohibition works.

What arguments for legalization have to rely upon is that marijuana isn’t evil – at least, isn’t evil in the way that harder drugs are, or is at least as benign as currently-legal substances like alcohol or nicotine. As Ed reported last month, though, we shouldn’t trick ourselves into thinking that marijuana is actually harmless.

Regardless, with majorities of people for the first time supporting legalization, it’s a drug we might have to become more comfortable with. Medicinal use has become much more common over the last ten years, and we’re starting to see the acceptance of recreational use as well. And make no mistake, the relaxation of marijuana laws will absolutely lead to an increase in marijuana usage. What matters is if that’s something that should be morally acceptable – and that it would be outweighed by some of the horrors of the drug war.