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 Missouri, the primary laws governing the operation of vehicles while under the influence of alcohol or drugs are found under the state's Revised Statutes, specifically in Chapter 577, which deals with public safety offenses. The state uses the terms 'Driving While Intoxicated' (DWI) and 'Driving Under the Influence' (DUI) to refer to the criminal offense of operating a motor vehicle while impaired. Missouri law defines intoxication not only by alcohol but also by drugs or a combination thereof. A person is considered to be driving while intoxicated if they operate a vehicle with a blood alcohol content (BAC) of 0.08% or higher, or if they are visibly impaired by alcohol or drugs. The state also has a 'Zero Tolerance Law' for drivers under the age of 21, who can be charged with a DUI for any detectable amount of alcohol. Additionally, Missouri has laws for Boating While Intoxicated (BWI) that apply to operating watercraft under the influence, which are similar to the state's DWI laws. Penalties for these offenses can include fines, jail time, license suspension, and mandatory participation in substance abuse programs.