What is the legal BAC level that defines driver intoxication in the United States?

In the United States, a Blood Alcohol Concentration (BAC) level of .08 is the legal threshold that defines intoxication for drivers aged 21 and older. This means that if a driver has a BAC of .08% or higher, they are considered impaired and can be prosecuted for driving under the influence (DUI). The rationale behind this standard is based on research demonstrating that at this level of alcohol in the bloodstream, a driver’s ability to safely operate a vehicle is significantly impaired, leading to increased risks of accidents and fatalities.

In contrast, lower BAC levels, such as .05 or .10, may indicate some degree of impairment, but they are not the legal standard for intoxication as defined by federal and state laws. Additionally, certain states have stricter regulations for commercial drivers and underage individuals, often setting lower legal limits to account for differing levels of risk and responsibility. Hence, .08 is widely recognized as the benchmark for driver intoxication across the country.