I've seen conflicting articles claiming that DUI fatalities either increased or decreased after states legalized marijuana. Here are two samples, though there are many articles out there;
http://www.today.com/health/driving-while-high-marijuana-causing-spike-fatal-accidents-t91746
My question, do studies suggest legalization of marijuana results in a net increased or decrease in DUI fatalities?
For this question DUI includes deaths due to alcohol, marijuana, or any other substance that can cause a DUI.
I am looking at all states which legalized marijuana, not any one state. In fact I would accept studies from locations outside of the US if they were relevant in predicting the affect on DUI fatalities that would occur from a country legalizing marijuana.
I'd be interested in the affect of non-fatal accidents as well if found, though I only require information on fatalities for this question.
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