In a car crash or other incident involving multiple vehicles the police may investigate whether the driver of any of the vehicles is under the influence of or intoxicated by alcohol or drugs, and are not limited to investigating and arresting only the driver who was at fault in the accident, for example.
In Idaho, as in many states, law enforcement officers have the authority to investigate any driver involved in a car crash for driving under the influence (DUI) of alcohol or drugs, regardless of who is at fault for the accident. If an officer has reasonable grounds to believe that a driver is under the influence, they may conduct field sobriety tests, request breathalyzer or chemical tests, and, if sufficient evidence is found, arrest the driver for DUI. Idaho's DUI laws are codified in Idaho Code Title 18, Chapter 80, which outlines the procedures for DUI investigations and the penalties for offenses. It's important to note that all drivers involved in an accident can be subject to investigation, not just the driver who caused the crash.