Beauvois v. State
In Beauvois v. State 837 P.2d 1118 (Alaska App. 1992), the Court recognized the authority of the police to "approach and stop a person for the purpose of investigating a crime even though the officer has no reason to believe that the person stopped has committed the crime which is being investigated." However, the police are justified in stopping witnesses "only where exigent circumstances are present".
The facts of Beauvois provide an illustration of the exigency required to support an investigative stop of a witness.
In Beauvois, the police officer knew that a robbery had just occurred in the vicinity of a campground and that the robber had fled on foot toward the campground:
The time was three o'clock in the morning, when most people are asleep. The streets leading to the campground were deserted. The officer saw only one vehicle moving: the Corvette leaving the campground. It was reasonable to suspect that the occupants of the Corvette had been awake in the campground when the robber came through, and that they might have seen something. Under these circumstances, and especially given the recency and the seriousness of the crime, prompt investigative efforts were justified. Even though the officer had no other information to link the Corvette or its occupants to the robbery, he could validly stop the car and ask its occupants if they knew anything or had seen anything that might aid the officer's investigation of the crime that had just been committed. (Beauvois, 837 P.2d at 1121.)