Scott Alexander loosely concludes that marijuana legalization may not be worth the extra traffic accidents.
If this interpretation is true, we should expect that a mature legal marijuana industry causes about a 5% increase in car crashes and fatalities.and,
In the current set of nine states with legalization, the 5% increase would amount to an extra 300 deaths per year. If the country as a whole legalized, that would make about 1800 extra deaths per year. Using my totally made-up math model from the previous post, this is enough to shift the net effect of marijuana legalization from positive to slightly negative. This is especially true if the alternative to legalization is decriminalization, which has many of the benefits of legalization but fewer costs.I don't care what side Scott Alexander comes to. What is important to understand is that this is how the analysis should be done. He uses the problem solving module in his head rather than the war one.
