The following data provides estimates of alcohol involvement in fatal crashes for the United States and individually for the 50 States, the District of Columbia, and Puerto Rico (not included in the national totals). These estimates are based on data from NHTSA’s Fatality Analysis Reporting System (FARS). Unfortunately, known blood alcohol concentration (BAC) test results are not available for all drivers and non-occupants involved in fatal crashes. Missing data can result for a number of reasons, the most frequent of which is that people are not always tested for alcohol. To address the missing data issue, NHTSA has developed and employs a statistical model to estimate the blood alcohol concentration (BAC) of the driver or the non-occupant at the time of the crash. The statistical model is based on important characteristics of the crash including crash factors (e.g., time of day, day of week, type of crash, location); vehicle factors (e.g., vehicle type and role in the crash); and person factors (e.g., age, sex, restraint use, previous driving violations); and most importantly, the subjective assessment of the police officer at the scene of the crash as to whether alcohol was involved or not. The statistical model was developed using all available known data in the aggregate (that is, at the national level) and applied to each individual driver and non-occupant with an unknown BAC test result. The estimates presented include a mix of both known and estimated BACs. All 50 States, the District of Columbia, and Puerto Rico have by law created a threshold making it illegal per se to drive with a BAC of .08 grams per decilitre (g/dL) or higher. Drivers are considered to be alcohol-impaired when their BAC is .08 g/dL or higher. Thus, any fatality occurring in a crash involving a driver with a BAC of .08 or higher is considered to be an alcohol-impaired-driving fatality. The term “driver” refers to the operator of any motor vehicle, including a motorcycle. The term “alcohol-impaired” does not indicate that a crash or a fatality was caused by alcohol impairment. Great caution should be exercised in comparing the levels of alcohol involvement among States. Differences in alcohol involvement can be due to any number of factors not necessarily directly related to a State’s alcohol traffic safety program. (Author/publisher)
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