United States v. Arvizu

A Border Patrol Agent received information that a vehicle sensor had been triggered in a remote area. The agent suspected that the vehicle could be attempted to evade a checkpoint as the timing corresponded with a shift change, leaving the area unpatrolled. The agent located the vehicle, a minivan. He obtained a visual vantage point by pulling off to the side of the road at an angle so he could see the oncoming vehicle as it passed by. The agent observed (1) the vehicle slow considerably as it approached his position, (2) the driver appear stiff and rigid, (3) the driver seemed to pretend the agent was not there, (3) the knees of the passengers (children) in the very back seat were unusually high (as if their feet were elevated by something on the floor). The agent followed the vehicle for a short distance and observed (4) the children, while facing forward, wave at the agent in an abnormal fashion, (5) the strange waving continued intermittently for four to five minutes, (6) the driver signaled for a turn, turned the signal off, then suddenly signaled and turned the vehicle, (7) the turn was the last that would allow the vehicle to avoid the checkpoint, (8) the road is rough and usually utilized by four-wheel-drive vehicles, (9) the vehicle did not appear to be part of the local traffic and (10) there were no recreation areas associated with this road. The agent requested vehicle registration information via the radio and learned that (11) the vehicle was registered to an address four blocks north of the border in an area known for alien and narcotics smuggling.