According to a new study from the Journal of Studies on Alcohol and Drugs, you might want to be more careful about who drives you home after a night out—or exercise more caution yourself. CBS News with topline takeaway (emphasis added):
The study ... looked at 1,071 bar patrons —165 of whom were designated drivers—over a 3-month period. The majority of the patrons were white male college students. ... About 40 percent of the designated drivers in the study had something to drink. After being given breath tests, about 17 percent had blew a 0.02 to 0.049 reading. Eighteen percent had a BrAC of 0.05 or higher, suggesting impairment.
Obviously, we're working with a pretty limited sample, so no one's suggesting that the study is definitive. Still, the findings are clearly troubling, and are already generating a fair amount of headlines. Although the legal limit is 0.08, the latest research indicates that impairment—namely, slower reaction times and poorer motor skills—can begin at levels as low as 0.02 and is almost always present by 0.05. That's a big reason reason why the National Transportation Safety Board floated a plan last month to cut the legal limit to 0.05. (Of course, as Slate's Justin Peters pointed out then, it's not entirely clear whether such a move would actually curb drunk-driving deaths.)