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 Connecticut, operating a motorized vehicle while under the influence of alcohol or drugs is a serious criminal offense. The state uses the term 'Operating Under the Influence' (OUI) to describe such offenses, which is covered under Connecticut General Statutes Section 14-227a. The law applies to all motor vehicles, including cars, motorcycles, and in some cases, bicycles, if they are motorized. Additionally, Connecticut has laws against Boating Under the Influence (BUI), which is governed by Section 15-133 of the General Statutes. These laws prohibit operating a vessel on waterways while intoxicated. The legal blood alcohol concentration (BAC) limit in Connecticut is 0.08% for drivers over the age of 21, and 0.02% for those under 21. Penalties for OUI/BUI can include fines, imprisonment, community service, and the suspension of driving or boating privileges. The state may also require participation in an alcohol education program. Repeat offenders face increased penalties, and Connecticut has an implied consent law, meaning that refusal to submit to a BAC test can result in license suspension.