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 Maryland, driving under the influence (DUI) and driving while impaired (DWI) are serious criminal offenses. A DUI typically refers to operating a vehicle with a blood alcohol concentration (BAC) of 0.08% or higher, while DWI may be charged with a BAC of 0.07% or lower, depending on other evidence of impairment. Maryland law also includes operating under the influence (OUI) offenses for those operating watercraft while intoxicated, known as boating under the influence (BUI). Penalties for these offenses can include fines, imprisonment, and the suspension or revocation of driving privileges. The specific statutes detailing these offenses and their penalties can be found in the Maryland Transportation Code and the Natural Resources Code for BUI. It's important to note that Maryland has an implied consent law, meaning that if you drive on Maryland roads, you have consented to a chemical test for alcohol or drugs if suspected of DUI or DWI.