HOKIT

In this case the defendant was stopped one evening when she was driving westbound on Highway 80 in a rural area of San Diego County. Border patrol agents had been alerted by a signal from a motion sensor placed along a dirt road, which was a public roadway, leading from some residences near the international border to Highway 80. The agents did not see the car, if any, which tripped the sensor, nor did they see the defendant exit that road onto Highway 80. They concluded, however, from the timing of the signal that the car they saw on the highway was probably the one that tripped the sensor. As they followed the car, they did not observe any significant suspicious behavior, did not believe the defendant was a foreign national, observed no Vehicle Code violations, and the car was properly registered. In short, the agents stopped the car because it was routine practice to stop any car coming from the area of the sensor, located on a public road about one-half mile inside the United States, for an immigration check.

Thus, this appeal presents the question of whether a person who may have driven by a border patrol sensor which has been placed along a public roadway, without…