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 Mississippi, the primary statute governing the operation of vehicles under the influence of alcohol or drugs is Section 63-11-30 of the Mississippi Code. This law prohibits operating a motor vehicle on any road, street, or highway in Mississippi while under the influence of alcohol, drugs, or any substance that impairs the driver's ability to operate the vehicle safely. The legal blood alcohol concentration (BAC) limit in Mississippi is 0.08% for drivers aged 21 and over, and 0.02% for drivers under the age of 21. For commercial drivers, the limit is 0.04%. The state refers to these offenses as DUI (Driving Under the Influence). Penalties for DUI convictions in Mississippi can include fines, imprisonment, mandatory attendance at a victim impact panel, and the suspension or revocation of the driver's license. Additionally, Mississippi law also addresses BUI (Boating Under the Influence) under Section 59-23-7, which prohibits operating a watercraft while intoxicated. The BAC limits and the implications of BUI are similar to those for DUI, including potential fines and incarceration.