CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR THE NINTH CIRCUIT
Burger, Brennan, Stewart, White, Marshall, Blackmun, Powell, Rehnquist, Stevens.
MR. JUSTICE POWELL delivered the opinion of the Court.
These cases involve criminal prosecutions for offenses relating to the transportation of illegal Mexican aliens. Each defendant was arrested at a permanent checkpoint operated by the Border Patrol away from the international border with Mexico, and each sought the exclusion of certain evidence on the ground that the operation of the checkpoint was incompatible with the Fourth Amendment. In each instance whether the Fourth Amendment was violated turns primarily on whether a vehicle may be stopped at a fixed checkpoint for brief questioning of its occupants even though there is no reason to believe the particular vehicle contains illegal aliens. We reserved this question last Term in United States v. Ortiz, 422 U.S. 891, 897 n. 3 (1975). We hold today that such stops are consistent with the Fourth Amendment. We also hold that the operation of a fixed checkpoint need not be authorized in advance by a judicial warrant.
The respondents in No. 74-1560 are defendants in three separate prosecutions resulting from arrests made on three different occasions at the permanent immigration checkpoint on Interstate 5 near San Clemente, Cal. Interstate 5 is the principal highway between San Diego and Los Angeles, and the San Clemente checkpoint is 66 road miles north of the Mexican border. We previously have described the checkpoint as follows: S
"'Approximately one mile south of the checkpoint is a large black on yellow sign with flashing yellow lights over the highway stating "ALL VEHICLES, STOP AHEAD, 1 MILE." Three-quarters of a
mile further north are two black on yellow signs suspended over the highway with flashing lights stating "WATCH FOR BRAKE LIGHTS." At the checkpoint, which is also the location of a State of California weighing station, are two large signs with flashing red lights suspended over the highway. These signs each state "STOP HERE -- U.S. OFFICERS." Placed on the highway are a number of orange traffic cones funneling traffic into two lanes where a Border Patrol agent in full dress uniform, standing behind a white on red "STOP" sign checks traffic. Blocking traffic in the unused lanes are official U.S. Border Patrol vehicles with flashing red lights. In addition, there is a permanent building which houses the Border Patrol office and temporary detention facilities. There are also floodlights for nighttime operation.'" United States v. Ortiz, supra, at 893, quoting United States v. Baca, 368 F. Supp. 398, 410-411 (SD Cal. 1973).I
The "point" agent standing between the two lanes of traffic visually screens all northbound vehicles, which the checkpoint brings to a virtual, if not a complete, halt.*fn1 Most motorists are allowed to resume their progress without any oral inquiry or close visual examination. In a relatively small number of cases the "point" agent will conclude that further inquiry is in order. He directs these cars to a secondary inspection area, where their occupants are asked about their citizenship and immigration status. The Government informs us that at San
Clemente the average length of an investigation in the secondary inspection area is three to five minutes. Brief for United States 53. A direction to stop in the secondary inspection area could be based on something suspicious about a particular car passing through the checkpoint, but the Government concedes that none of the three stops at issue in No. 74-1560 was based on any articulable suspicion. During the period when these stops were made, the checkpoint was operating under a magistrate's "warrant of inspection," which authorized the Border Patrol to conduct a routine-stop operation at the San Clemente location.*fn2
We turn now to the particulars of the stops involved in No. 74-1560, and the procedural history of the case. Respondent Amado Martinez-Fuerte approached the checkpoint driving a vehicle containing two female passengers. The women were illegal Mexican aliens who had entered the United States at the San Ysidro port of entry by using false papers and rendezvoused with Martinez-Fuerte in San Diego to be transported northward. At the checkpoint their car was directed to the secondary inspection area. Martinez-Fuerte produced documents showing him to be a lawful resident alien, but his passengers admitted being present in the country unlawfully. He was charged, inter alia, with two counts of illegally transporting aliens in violation
of 8 U.S.C. § 1324(a)(2). He moved before trial to suppress all evidence stemming from the stop on the ground that the operation of the checkpoint was in violation of the Fourth Amendment.*fn3 The motion to suppress was denied, and he was convicted on both counts after a jury trial.
Respondent Jose Jiminez-Garcia attempted to pass through the checkpoint while driving a car containing one passenger. He had picked the passenger up by prearrangement in San Ysidro after the latter had been smuggled across the border. Questioning at the secondary inspection area revealed the illegal status of the passenger, and Jiminez-Garcia was charged in two counts with illegally transporting an alien, 8 U.S.C. § 1324(a)(2), and conspiring to commit that offense, 18 U.S.C. § 371. His motion to suppress the evidence derived from the stop was granted.
Respondents Raymond Guillen and Fernando Medrano-Barragan approached the checkpoint with Guillen driving and Medrano-Barragan and his wife as passengers. Questioning at the secondary inspection area revealed that Medrano-Barragan and his wife were illegal aliens. A subsequent search of the car uncovered three other illegal aliens in the trunk. Medrano-Barragan had led the other aliens across the border at the beach near Tijuana, Mexico, where they rendezvoused with Guillen, a United States citizen. Guillen and Medrano-Barragan were jointly indicted on four counts of illegally transporting
aliens, 8 U.S.C. § 1324(a)(2), four counts of inducing the illegal entry of aliens, § 1324(a)(4), and one conspiracy count, 18 U.S.C. § 371. The District Court granted the defendants' motion to suppress.
Martinez-Fuerte appealed his conviction, and the Government appealed the granting of the motions to suppress in the respective prosecutions of Jiminez-Garcia and of Guillen and Medrano-Barragan.*fn4 The Court of Appeals for the Ninth Circuit consolidated the three appeals, which presented the common question whether routine stops and interrogations at checkpoints are consistent with the Fourth Amendment.*fn5 The Court of Appeals held, with one judge dissenting, that these stops violated the Fourth Amendment, concluding that a stop for inquiry is constitutional only if the Border Patrol reasonably suspects the presence of illegal aliens on the basis of articulable facts. It reversed Martinez-Fuerte's conviction, and affirmed the orders to suppress in the other cases. 514 F.2d 308 (1975). We reverse and remand.
Petitioner in No. 75-5387, Rodolfo Sifuentes, was arrested at the permanent immigration checkpoint on U.S. Highway 77 near Sarita, Tex. Highway 77 originates in Brownsville, and it is one of the two major highways running north from the lower Rio Grande valley. The Sarita checkpoint is about 90 miles north of Brownsville,
and 65-90 miles from the nearest points of the Mexican border. The physical arrangement of the checkpoint resembles generally that at San Clemente, but the checkpoint is operated differently in that the officers customarily stop all northbound motorists for a brief inquiry. Motorists whom the officers recognize as local inhabitants, however, are waved through the checkpoint without inquiry. Unlike the San Clemente checkpoint the Sarita operation was conducted without a judicial warrant.
Sifuentes drove up to the checkpoint without any visible passengers. When an agent approached the vehicle, however, he observed four passengers, one in the front seat and the other three in the rear, slumped down in the seats. Questioning revealed that each passenger was an illegal alien, although Sifuentes was a United States citizen. The aliens had met Sifuentes in the United States, by prearrangement, after swimming across the Rio Grande.
Sifuentes was indicted on four counts of illegally transporting aliens. 8 U.S.C. § 1324(a)(2). He moved on Fourth Amendment grounds to suppress the evidence derived from the stop. The motion was denied and he was convicted after a jury trial. Sifuentes renewed his Fourth Amendment argument on appeal, contending primarily that stops made without reason to believe a car is transporting aliens illegally are unconstitutional. The United States Court of Appeals for the Fifth Circuit affirmed the conviction, 517 F.2d 1402 (1975), relying on its opinion in United States v. Santibanez, 517 F.2d 922 (1975). There the Court of Appeals had ruled that routine checkpoint stops are consistent with the Fourth Amendment. We affirm.*fn6
The Courts of Appeals for the Ninth and the Fifth Circuits are in conflict on the constitutionality of a law enforcement technique considered important by those charged with policing the Nation's borders. Before turning to the constitutional question, we examine the context in which it arises.
It has been national policy for many years to limit immigration into the United States. Since July 1, 1968, the annual quota for immigrants from all independent countries of the Western Hemisphere, including Mexico, has been 120,000 persons. Act of Oct. 3, 1965, § 21(e), 79 Stat. 921. Many more aliens than can be accommodated under the quota want to live and work in the United States. Consequently, large numbers of aliens seek illegally to enter or to remain in the United States. We noted last Term that "[e]stimates of the number of illegal immigrants [already] in the United States vary widely. A conservative estimate in 1972 produced a figure of about one million, but the Immigration and Naturalization Service now suggests there may be as many as 10 or 12 million aliens illegally in the country." United States v. Brignoni-Ponce, 422 U.S. 873, 878 (1975) (footnote omitted). It is estimated that 85% of the illegal immigrants are from Mexico, drawn by the fact that economic opportunities are significantly greater in the United States than they are in Mexico. United States v. Baca, 368 F. Supp., at 402.
Interdicting the flow of illegal entrants from Mexico poses formidable law enforcement problems. The principal problem arises from surreptitious entries. Id., at 405. The United States shares a border with Mexico that is almost 2,000 miles long, and much of the border area is uninhabited desert or thinly populated arid land. Although the Border Patrol maintains personnel, electronic equipment, and fences along portions of the border, it remains relatively easy for individuals to enter the United States without detection. It also is possible for an alien to enter unlawfully at a port of entry by the use of falsified papers or to enter lawfully but violate restrictions of entry in an effort to remain in the country unlawfully.*fn7 Once within the country, the aliens seek to travel inland to areas where employment is believed to be available, frequently meeting by prearrangement with friends or professional smugglers who transport them in private vehicles. United States v. Brignoni-Ponce, supra, at 879.
The Border Patrol conducts three kinds of inland traffic-checking operations in an effort to minimize illegal immigration. Permanent checkpoints, such as those at San Clemente and Sarita, are maintained at or near intersections of important roads leading away from the border. They operate on a coordinated basis designed to avoid circumvention by smugglers and others who transport the illegal aliens. Temporary checkpoints, which operate like permanent ones, occasionally are established in other strategic locations. Finally, roving patrols are maintained to supplement the checkpoint system. See Almeida-Sanchez v. United Page 553} States, 413 U.S. 266, 268 (1973).*fn8 In fiscal 1973, 175,-511 deportable aliens were apprehended throughout the Nation by "line watch" agents stationed at the border itself. Traffic-checking operations in the interior apprehended approximately 55,300 more deportable aliens.*fn9 Most of the traffic-checking apprehensions were at checkpoints, though precise figures are not available. United States v. Baca, supra, at 405, 407, and n. 2.
We are concerned here with permanent checkpoints, the locations of which are chosen on the basis of a number of factors. The Border Patrol believes that to assure effectiveness, a checkpoint must be (i) distant enough from the border to avoid interference with traffic in populated areas near the border, (ii) close to the confluence of two or more significant roads leading away from the border, (iii) situated in terrain that restricts vehicle passage around the checkpoint, (iv) on a stretch of highway compatible with safe ...