Alcohol and the Law

Driving skills are affected adversely in most people beginning at a BAC of just .05%.

The U.S. National Highway Traffic Safety Administration (NHTSA) has made it illegal to operate a motor vehicle with a BAC at or above .10%. Each state has its own laws about the BAC level that equals "driving under the influence" (DUI) or "driving while intoxicated" (DWI). Most states use .10% as the legal definition of "intoxicated" for drivers aged 21 and above. Nineteen states and the District of Columbia have lowered that limit to .08%. Massachusetts is the only state that does not prohibit drinking and driving with a specific BAC level.

Some states also have adopted a zero-tolerance standard for teenage drivers. Violators have their licenses suspended and face other legal consequences for operating a motor vehicle with any detectable blood-alcohol levels.

The following are BAC-related data for the 50 states and the District of Columbia for the first offense only. All states impose fines, ranging from $100 to $1000 for the first offense. States also have jail time guidelines, which range from 48 hours to two years, depending on the state and the severity of the offense. Some states also impound vehicles from one to thirty days. Penalties are increased dramatically with second, third, and subsequent offenses. In many states, a fourth offense is an automatic felony with penitentiary time attached.