Pot by itself was not much of a factor in injury and fatal crashes probed last year by the Arizona Department of Public Safety. Fewer than 1 percent of suspected impaired drivers involved in such crashes tested positive for nothing but marijuana.
Drivers suspected of impairment in crashes that hurt or killed people in Phoenix, Chandler, and Scottsdale were rarely found to be impaired by marijuana, according to research from the Phoenix New Times. Meanwhile, alcohol is believed responsible for five to 10 times the number of crashes caused by drivers impaired by all other illegal drugs combined. The New Times has the rest.