From 1994 through 2011, the United States has made substantial strides in reducing overall alcohol involvement in fatal crashes. Since this article explores only the involvement of law enforcement in a particular facet of roadside interventions, that is, alcohol-impaired driving, this introductory analysis examines possible changes influenced by the subject training on fatal crash–involved drivers rather than on the fatalities themselves.

The total number of persons killed in fatal crashes fell by 21 percent, from 40,716 in 1994 to 32,367 in 2011. The number of drivers with a reported blood alcohol concentration (BAC) equal to or greater than .08 grams per deciliter declined almost 41 percent, from 16,589 in 1994 to 9,878 in 2011.