What constitutes "driving under the influence" (DUI) in California?

In California, "driving under the influence" (DUI) is defined primarily by operating a vehicle with a blood alcohol concentration (BAC) of 0.08% or higher. This legal threshold signifies a level at which a driver's ability to operate a vehicle safely is compromised due to alcohol consumption. Additionally, the law encompasses scenarios where a person's driving ability is impaired by drugs, whether they be illegal, prescription, or over-the-counter medications.

This dual focus on both alcohol and drugs reflects the state's commitment to road safety, recognizing that impairment can arise from various substances. It is crucial for drivers to understand not only the BAC limit but also that any substance that affects coordination, judgment, or reaction times can lead to DUI charges.

Other choices present scenarios that may involve unsafe driving but do not constitute DUI under California law. For instance, a BAC of 0.05% is considered under the legal limit for adults over 21, while driving distracted by texting does not fall under the DUI category, though it is still illegal and dangerous. Lastly, driving while fatigued is a serious safety issue, but the law does not classify it as DUI. Understanding these definitions and legal boundaries is key for responsible driving behavior.