What does the term "driving under the influence" (DUI) encompass?

The term "driving under the influence" (DUI) specifically refers to operating a vehicle while impaired by alcohol, drugs, or both. This definition is critical in traffic law as it addresses the impairment of a driver's ability to safely operate a vehicle due to intoxicating substances. In Indiana, as in many other jurisdictions, the law defines DUI based on a driver's blood alcohol concentration (BAC) and the influence of drugs, which can significantly impair judgment, coordination, and reaction times.

The focus of DUI legislation is primarily on the safety risks posed by drivers who are impaired, as such impairment can lead to accidents, injuries, and fatalities. Therefore, the clear inclusion of both alcohol and drugs in this definition highlights the comprehensive nature of DUI laws designed to maintain road safety and deter impaired driving.

The other options refer to different issues related to driving but do not fall under the specific legal definition of DUI. For example, driving while fatigued may affect a driver's performance but is not classified legally as DUI. Similarly, driving without a valid driver's license and speeding in school zones are distinct traffic violations that pertain to licensing and speed regulations rather than impairment from substances.