People continue to drive impaired by alcohol and drugs, but good enforcement can deter them.
Progress has been made during the past 20 years to reduce the proportion of fatally injured drivers with blood alcohol concentrations (BACs) at or above 0.08 percent. Proportions are lower in all age groups and among vehicle drivers. There also has been a substantial decline among those with very high BACs (at or above 0.15 percent), who often are assumed to be "hard-core" drinking drivers. However, progress has stalled in recent years and alcohol-impaired driving is still a major problem.
All states now have enacted a law defining impairment as driving with a BAC at or above 0.08 percent. In addition, all states also have "zero tolerance" laws that prohibit people younger than 21 from driving after drinking. Typically, these laws prohibit driving with a BAC of 0.02 percent or greater. The probability of a fatal crash rises significantly after 0.05 percent BAC and even more rapidly after about 0.08 percent. Zador, P.L.; Krawchuck, S.; and Voas, R.B. 2000. Alcohol-related relative risk of driver fatalities and driver involvement in fatal crashes in relation to driver age and gender: an update using 1996 data. Journal of Studies on Alcohol 61:387-95. Among drivers age 35 and older with BACs at or above 0.15 percent on weekend nights, the likelihood of dying in a single-vehicle crash is 382 times higher than it is for nondrinking drivers. Zador, P.L.; Krawchuck, S.; and Voas, R.B. 2000. Alcohol-related relative risk of driver fatalities and driver involvement in fatal crashes in relation to driver age and gender: an update using 1996 data. Journal of Studies on Alcohol 61:387-95.
The information in this fact sheet is based on data from all 50 states and the District of Columbia with imputations for missing BACs provided by the U.S. Department of Transportation's multiple imputation model. Subramanian, R. 2002. Transitioning to multiple imputation — a new method to impute missing blood alcohol concentration (BAC) values in FARS. Report no. DOT HS-809-403. Washington, DC: U.S. Department of Transportation.
The following facts are based on analysis of data from the U.S. Department of Transportation's Fatality Analysis Reporting System (FARS).
The percentage of fatally injured motor vehicle drivers with BACs at or above 0.08 percent declined steadily from the 1980s to the mid-1990s. Since then, little progress has been made. Since 1997 about a third of fatally injured passenger vehicle drivers have had BACs of 0.08 percent or above. In 2006, the group of fatally injured drivers with the lowest proportion of BACs at or above 0.08 percent was tractor-trailer drivers (5 percent). In 2006, the group with the highest proportion of BACs at or above 0.08 percent was pedestrians ages 16 and older (37 percent).
Percent of fatally injured people with BACs ≥0.08 percent by type, 1982-2006
The percentage of fatally injured drivers with BACs of 0.15 percent or higher has declined 36 percent since 1982 but with little change since 1997. The proportion of driver deaths involving BACs at or above 0.15 percent in 2006 was 24 percent for passenger vehicles and 16 percent for motorcycles. A higher percentage of pedestrians (29 percent) had BACs at or above 0.15 percent than did any group of drivers.
Among fatally injured passenger vehicle drivers in 2006, a higher proportion of males than females had BACs at or above 0.08 percent at every age. Overall 38 percent of males and 22 percent of females had BACs at or above 0.08 percent. The percentage was highest among males ages 21-40.
Among fatally injured passenger vehicle drivers in 2006, 28 percent of males and 15 percent of females had BACs at or above 0.15 percent.
Since the 1980s the proportion of fatally injured passenger vehicle drivers with BACs at or above 0.08 percent declined more among 16-20 year-olds than among older drivers, but these declines ended in 1995.
Percent of fatally injured passenger vehicle drivers with BACs ≥0.08 percent by driver age, 1982-2006
Alcohol involvement in fatal crashes peaks at night. Between 9pm and 6am, 58 percent of fatally injured passenger vehicle drivers in 2006 had BACs at or above 0.08 percent, compared with 18 percent during other hours.
Forty-five percent of passenger vehicle drivers fatally injured on weekends (6 pm Friday to 6 am Monday) in 2006 had BACs at or above 0.08 percent, compared with 24 percent at other times.
Alcohol involvement is highest in nighttime (9 pm to 6 am) single-vehicle crashes, in which 66 percent of fatally injured passenger vehicle drivers in 2006 had BACs at or above 0.08 percent. Only 28 percent of the fatally injured passenger vehicle drivers involved in nighttime single-vehicle crashes had no alcohol in their blood. Changes in nighttime single-vehicle crashes often are used to measure the changing role of alcohol in highway crashes and crash deaths.
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