They are under the influence of alcohol or drugs or any combination that makes them incapable of safely operating a motor vehicle; or
If their blood alcohol content (BAC) when they are subjected to a breathalyzer is 0.08 grams or more of alcohol for every 100 ml of blood or 0.08 grams or more of alcohol for every 210 liters of breath; or
A federal OUI is usually a Class B misdemeanor with a maximum punishment, if convicted, of up to six months in jail, supervised probation for up to five years, or a fine not up to $5000.