COUNTRIES that decriminalise marijuana use generally do so under the rubric of "harm reduction". Certainly, they concede, smoking marijuana has some negative effects, but they are far outweighed by the negative effects of sending people to jail for it (creation of a vast underground criminal economy, promoting gang violence, destroying users' lives and earning potential, costing taxpayers money, etc). We don't criminalise tobacco or alcohol use, and it seems strange to jail people for another drug whose negative effects are at worst similar: a bit of addled thinking, possibly severe addlement in the case of long-term heavy users, and presumably pulmonary disease and lung cancer.

Or...maybe no pulmonary disease or lung cancer, either. Aaron Caroll sends us to a new study published in the Journal of the American Medical Association. He summarises:

Basically, researchers followed more than 5000 men and women over 20 years to see how smoking tobacco and marijuana affected lung health. What did they find? Not surprisingly, tobacco use had significant negative effects on lung function. Marijuana use, though, had none. No lung effects at all. They couldn't even show that very high use of marijuana was bad for lung function, although the study wasn't powered for that analysis.

This is really over the top. I would have expected that the researchers would have found at least some negative effects on lung function. And maybe if they had been primed to look at "extremely high use" they might have found some; I know at least one longtime serious toker who's developed emphysema. But the low level of harm here is amazing. A couple of years back, when Amsterdam instituted no-smoking rules in bars and restaurants, everyone had a good laugh at the fact that it was now perfectly okay to light up a joint in the city's famous "coffee shops", but if you pulled out a cigarette the owner would kick you out lest the police show up. Now it seems the rule had the order of harm exactly right.

How much longer are we going to continue with this nonsense?

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