There are various criminal charges for operating a motorized, electric, or otherwise-powered transportation device on public roadways or waterways while under the influence of or intoxicated by drugs or alcohol, as defined by state law. DUI, DWI, OUI, OWI, and BUI—driving under the influence, driving while intoxicated, operating under the influence, operating while intoxicated, and boating under the influence—are some of the common names for such impaired-driving or impaired-operating criminal offenses.

Laws regarding the definitions and names of such alcohol and drug-related driving offenses vary from state to state and are usually located in a state’s statutes—often in the penal code or criminal code.

In Illinois, the primary statute governing the operation of vehicles while under the influence of alcohol, drugs, or other intoxicating compounds is the Illinois Vehicle Code, specifically 625 ILCS 5/11-501. This law prohibits driving any vehicle while impaired by alcohol, drugs, or intoxicants with a blood-alcohol content (BAC) of 0.08% or higher. The offense is commonly referred to as Driving Under the Influence (DUI). Illinois law also addresses boating under the influence (BUI) under 625 ILCS 45/5-16, which makes it illegal to operate a watercraft while under the influence of alcohol, drugs, or intoxicating compounds. Penalties for DUI and BUI can include fines, imprisonment, community service, and the suspension or revocation of driving or boating privileges. The specific charges and penalties can vary based on factors such as the offender's BAC level, prior offenses, and whether the incident resulted in injury or property damage.