Kevin Drum’s not much of a pothead (“I’ve never smoked a joint in my life. I’ve only seen one once, and that was 30 years ago. I barely drink, I don’t smoke, and I don’t like coffee.”) but he’s come to the conclusion that we should decriminalize marijuana and wrote a great piece in Mother Jones about it. This isn’t really the key to the argument, but I was interested in this research on marijuana-alcohol substitutability:
He found that raising the drinking age did lead to lower alcohol consumption; the effect was modest but real. But then DiNardo hit on another analysis — comparing cannabis use in states that raised the drinking age early with those that did it later. And he found that indeed, there seemed to be a substitution effect. On average, among high school seniors, a 4.5 percent decrease in drinking produced a 2.4 percent increase in getting high.
I have smoked pot but frankly it’s just not something I enjoy very much. And anecdotally it’s definitely the case that my marijuana consumption plummeted as it got easier for me to buy alcohol. Conversely, my selfish reason for liking marijuana prohibition is that it reduces the extent to which friends want to engage in pot smoking — which I find unpleasant — as a social activity.
That said, back to the real world of public policy I think the only serious debate is over exactly how you want to manage decriminalization. If you really legalize pot and sell it in stores and such, then you can tax it. But the development of large-scale commercial enterprises dedicated to marijuana advertising would have deleterious effects. So maybe it’s better to do something Dutch-style where you’re not wasting law enforcement resources on curtailing the marijuana trade, but the technical illegality keeps things restrained.