Driving Under The Influence (DUI) Definition and Legal Meaning

On this page, you'll find the legal definition and meaning of Driving Under The Influence (DUI), written in plain English, along with examples of how it is used.

What is Driving Under The Influence (DUI)?

n. “Drunk driving.” Operating a motor vehicle with a blood alcohol content that is higher than the legal limit which has been set at a level at which a person cannot safely drive. The statutes range from .08 to .10 for adults which equates to 8/100ths to one-tenth of one percent by weight of alcohol to the weights of blood. For blood tests and urine samples, this is translated into grams of alcohol per 100 milliliters of blood, or grams of alcohol per 210 liters of air for breathalyzer tests. Based on erratic driving, a combination of the use narcotics and alcohol can classify as being “under the influence.” While driving on private property such as a parking lot is not a defense, sitting in a non-moving vehicle without the ignition on, may qualify as a DUI or DWI (driving while intoxicated) misdemeanor.

History and Meaning of Driving Under The Influence (DUI)

Driving Under the Influence, commonly shortened to DUI, is a term used to refer to the crime of operating a motor vehicle while impaired by alcohol or drugs, or both. The exact definition, legal limitations, and penalties associated with DUI may vary from country to country or state to state.

The history of DUI laws dates back to the early 1900s when Montana became the first state to enact laws to regulate drinking and driving. Since that time, many states in the U.S. have enacted stricter laws governing the offense, often due to the increasing numbers of accidents and fatalities related to impaired driving.

Examples of Driving Under The Influence (DUI)

  • John was stopped at a DUI checkpoint and found to have a blood alcohol content (BAC) of 0.10%, which is above the legal limit of 0.08%.
  • Mary was pulled over for swerving on the road, and the officer noticed the smell of alcohol on her breath. A field sobriety test revealed her BAC was over the legal limit.
  • Tom was arrested for DUI after causing an accident while driving under the influence of marijuana.
  • Ana was charged with DUI after she was found sleeping in the driver's seat of her car with the engine running, and her BAC was still above the legal limit.

Legal Terms Similar to Driving Under The Influence (DUI)

  • Driving While Intoxicated (DWI): This term is used in some jurisdictions instead of DUI, and it refers to operating a motor vehicle while under the influence of drugs or alcohol.
  • Operating Under the Influence (OUI): This term is used in some states to refer to operating a vehicle under the influence of drugs or alcohol.
  • Driving While Ability Impaired (DWAI): This term is often used to describe a lesser charge of impaired driving when the BAC is below the legal limit but above a set threshold.