Drunk driving is the act of operating a motor vehicle with the operator’s ability to do so impaired as a result of alcohol consumption, or with a blood alcohol level in excess of the legal limit. For drivers 21 years or older, driving with a blood alcohol concentration (BAC) of 0.08% or higher is illegal.

When your blood alcohol content (BAC) is 0.08% or higher, you’re considered legally impaired in the U.S. While you are certain to be arrested for suspicion of driving under the influence (DUI) when your BAC is at or over 0.08%, you can still be charged if your BAC is at any level above 0.00%.