As you can see, roadway fatalities this year are down from last year, and down from the 13-year average. Of the seven months so far this year, five months saw a lower fatality figure this year than last, two months saw a slightly higher figure this year, and in one month the two figures were equal. If we add up the total fatalities from January through July, it looks like this:



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That said, some researchers have gone so far as to suggest that better access to pot is making the roads safer, at least marginally. The theory is that people are substituting pot for alcohol, and pot causes less driver impairment than booze. I’d need to see more studies before I’d be ready to endorse that theory. For example, there’s also some research contradicting the theory that drinkers are ready to substitute pot for alcohol.

http://www.washingtonpost.com/news/the-watch/wp/2014/08/05/since-marijuana-legalization-highway-fatalities-in-colorado-are-at-near-historic-lows/