Everyone knows the dangers of drunk driving, but alcohol isn’t the only drug that poses a threat on the road. Among U.S. drivers who died in a car crash, about one in four tested positive for drugs such as marijuana, cocaine or amphetamines, a new study shows.
Researchers looked at a government reporting system that collects data on all U.S. traffic deaths. The data was limited to the 20 states that require drug tests for drivers involved in crashes, which, between 1998 and 2009 included 44,000 fatal auto crashes with available drug-test information for drivers.