United States v. Martinez-Fuerte

Supreme Court of the United States · 1976 · Criminal Procedure

428 U.S. 543 (1976)

Updated July 27, 2026

Criminal ProcedureFourth AmendmentBorder checkpointsImmigration enforcementseizurepermanent checkpointBorder Patrolreasonable suspicion

Facts

Each defendant was stopped at a permanent Border Patrol checkpoint located away from the Mexican border and challenged evidence obtained after the stop on Fourth Amendment grounds. At the San Clemente checkpoint, all northbound vehicles were visually screened and some were referred to a secondary inspection area for brief questioning; the government conceded the three challenged referrals there were not based on articulable suspicion, though the checkpoint was operating under a magistrate's warrant. At the Sarita checkpoint, officers customarily stopped all northbound motorists briefly, except recognized local residents, and no warrant authorized the operation. Questioning at secondary inspection or initial contact revealed illegal aliens in each vehicle, leading to prosecutions for transporting aliens.

Issue

May Border Patrol officers at a fixed, permanent immigration checkpoint stop vehicles for brief questioning of occupants without any individualized reasonable suspicion that the particular vehicle contains illegal aliens? If so, must such checkpoint operations be authorized in advance by a judicial warrant?

Rule

Stops for brief questioning routinely conducted at reasonably located permanent immigration checkpoints are consistent with the Fourth Amendment even absent individualized suspicion, and such checkpoint operations need not be authorized by warrant. Any further detention must rest on consent or probable cause, and checkpoint searches remain permissible only with consent or probable cause.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

On Interstate 25 north of Las Cruces, Border Patrol operates a fixed checkpoint marked by warning signs, cones, floodlights, and a permanent inspection booth. Every passing car is slowed and briefly asked where the occupants live and whether they are lawfully in the United States, even when agents have no individualized suspicion about a particular vehicle.

If a driver moves to suppress statements made during this brief stop solely because the agents lacked reasonable suspicion, how should the court rule?

Explanation. The majority held that routine stops for brief questioning at reasonably located permanent immigration checkpoints are reasonable under the Fourth Amendment even without individualized suspicion. The result rests on balancing the strong public interest in immigration control against the limited intrusion of a brief, visible, regularized checkpoint stop.