A person who believes they have had too much to drink to safely or legally drive may sit, lie, or fall asleep in their vehicle in a parking lot or parking space outside of a bar or restaurant, or may pull off the road and park to “sleep it off.” When the police observe a person occupying or sleeping in a parked car they may investigate if the car is illegally parked (on the side of the road or elsewhere) or for the stated purpose of checking on the well-being of the occupant of the vehicle.

After knocking on the window and attempting to wake the occupant of the vehicle the police will typically ask if the occupant was recently operating the vehicle and whether the occupant has had anything to drink. Based in part on the occupant’s answers to these questions the police may request the occupant submit to a breath or blood test, perform field sobriety tests, and may ultimately arrest the occupant for DUI/DWI.

Laws defining DUI/DWI criminal offenses vary from state to state and often include a person who is in physical control of a vehicle as being within the definition of operating a vehicle. Based on such a broad statutory definition of operating a vehicle—and depending on other factors such as (1) whether the occupant was in the driver’s seat of the vehicle or the back seat or passenger seat; (2) whether the vehicle’s engine was running; (3) whether the occupant was awake or asleep; and (4) whether the key, if any, was in the ignition—the police may arrest the occupant for DUI/DWI.

In Utah, a person who decides to 'sleep it off' in their vehicle to avoid driving under the influence may still face legal risks. Utah law considers a person to be in 'actual physical control' of a vehicle if they have the capability to operate the vehicle, regardless of whether they are driving at the time. Factors such as being in the driver's seat, having the keys in the ignition, or the engine running can all contribute to a determination of 'actual physical control.' If the police find someone in a parked car who appears to have been drinking, they may conduct an investigation that can include questioning, field sobriety tests, and breath or blood tests. Depending on the circumstances, the individual could be arrested for DUI (Driving Under the Influence) even if they were not observed driving. Utah's DUI laws are strict, and the state has a legal blood alcohol content (BAC) limit of 0.05%, which is lower than the 0.08% limit in many other states. It's important for individuals to be aware that even with good intentions, occupying a vehicle while intoxicated can lead to DUI charges in Utah.