Legal Definitions - DUI

DUI stands for Driving Under the Influence.

A DUI is a serious criminal offense that occurs when an individual operates a motor vehicle while their ability to drive safely is impaired by alcohol, illicit drugs, or even certain prescription medications. The legal standard for impairment can be based on a specific blood alcohol concentration (BAC) or evidence of physical or mental impairment due to drug use, regardless of whether the substance was legally obtained.

Here are some examples illustrating what constitutes a DUI:

• Example 1: Alcohol Impairment Beyond the Legal Limit

  Maria attends a company dinner and consumes several glasses of wine. Despite feeling capable of driving, her blood alcohol content (BAC) is later measured at 0.12%, which is above the legal limit of 0.08% in her state. A police officer observes her vehicle weaving slightly and pulls her over. Even if Maria doesn't appear overtly intoxicated, operating a vehicle with a BAC exceeding the legal threshold constitutes a DUI.

• Example 2: Impairment from Legally Prescribed Medication

  John is prescribed a strong sedative for anxiety. His doctor advises him not to drive while taking the medication due to its potential to cause drowsiness and slow reaction times. One afternoon, John takes his medication and then decides to drive to the store. While driving, he feels unusually lethargic and struggles to maintain focus on the road. If he were stopped by law enforcement and found to be impaired by the medication, he could face a DUI charge, as the legal status of the drug does not negate the impairment.

• Example 3: Impairment from Illicit Substances

  After consuming cannabis, Emily gets into her car to drive home. She experiences altered perception and delayed reflexes, making it difficult to judge distances and react quickly to traffic. An officer notices her driving erratically and pulls her over. A subsequent investigation confirms that Emily's driving ability was significantly impaired by the cannabis, leading to a DUI charge because operating a vehicle under the influence of illicit drugs is prohibited.