United States v. Brignoni-Ponce, 442 U.S. 873 (1975).

Facts: Officers were observing northbound traffic at the San Diego border and they stopped Brignoni-Ponce (“Respondent”) because, according to the officers, Respondent and his two passengers looked like Mexicans. After the stop, the officers discovered the two passengers were illegals and Respondent was convicted with two counts of transporting illegal immigrants.

Issue: Can an officer at the border stop a vehicle solely because of the foreign appearance of the occupants?

Holding: No.

Rationale: The Court noted that “[w]e are unwilling to let the Border Patrol dispense entirely with the requirement that officers must have a reasonable suspicion to justify roving-patrol stops. In the context of border area stops, the reasonableness requirement of the Fourth Amendment demands something more than the broad and unlimited discretion sought by the Government. Roads near the border carry not only aliens seeking to enter the country illegally, but a large volume of legitimate traffic as well.” According to the Court, “[t]o approve roving-patrol stops of all vehicles in the border area, without any suspicion that a particular vehicle is carrying illegal immigrants, would subject the residents of these and other areas to potentially unlimited interference.”

Thus, the Court held that “when an officer’s observation lead him reasonably to suspect that a particular vehicle may contain aliens who are illegally in the country, he may stop the car briefly and investigate the circumstances that provoke suspicion. As in Terry, the stop and inquiry must be ‘reasonably related in scope to the justification for their investigation.’” In this case, the Court observed that “the officers relied on a single factor to justify stopping Respondent’s car: the apparent Mexican ancestry of the occupants. We cannot conclude that this furnished reasonable grounds to believe that the three occupants were aliens. This factor alone would justify neither a reasonable belief that they were aliens, nor a reasonable belief that the car concealed other aliens.”