2018 Data: State Alcohol-Impaired-Driving Estimates

July 14th, 2020

All 50 States, the District of Columbia, and Puerto Rico have set a threshold making it illegal to drive with a blood alcohol concentration (BAC) of .08 grams per deciliter (g/dL) or higher. In addition, people under 21 are legally prohibited from drinking alcohol. Exceptions to this are:

Utah set a lower threshold of .05 g/dL or 2.
Operating a commercial vehicle at a higher that went into effect on December BAC of .04 g/dL or above is a violation 30, 2018. of Federal regulations and may result in criminal charges.

Drivers are considered to be alcohol-impaired when their BACs are .08 g/dL or higher. Thus, any fatality occurring in a crash involving a driver with a BAC of .08 g/dL 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 imply that a crash or a fatality was caused by alcohol impairment. This document also includes BACs of .00 g/dL (no alcohol), .01+ g/dL, and .15+ g/dL solely for comparison purposes.

Great caution is needed 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. Factors affecting alcohol involvement in fatal crashes include:

Population demographics and the
Types of vehicles (for example, motorcycle economic environment (for example, riders tend to have the highest levels of older drivers and female drivers tend to alcohol involvement, followed by drivers have lower levels of alcohol involvement). of light trucks; drivers of large trucks tend to have the lowest levels of alcohol involvement).

One of the major differences among States is the wide range of known testing results for drivers involved in fatal traffic crashes. In 2018 State-level percentages of known BACs of drivers involved ranged from a low of 27 percent in Kansas to a high of 83 percent in South Dakota (Table 5). These testing differences affect the accuracy and reliability of the estimates presented. States with higher percentages of known BACs are more likely to have accurate and precise estimates of fatal crash alcohol involvement.

Read the fact sheet here.