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 New Jersey, law enforcement officers have the authority to investigate any driver involved in a car crash or multi-vehicle incident for driving under the influence (DUI) of alcohol or drugs, regardless of who is at fault for the accident. New Jersey's DUI laws, codified under NJSA 39:4-50, do not limit officers to only investigate or arrest the driver who caused the accident. If an officer has reasonable suspicion or probable cause to believe that a driver is intoxicated, they can conduct field sobriety tests, administer a breathalyzer, or take other actions to determine impairment. If a driver is found to be under the influence, they can be arrested and charged with DUI, which carries serious penalties including fines, license suspension, and possible jail time.