United States v. Martinez-Fuerte

Syllabus

No. 74-1560. Argued April 26, 1976-Decided July 6, 1976*

1. The Border Patrol's routine stopping of a vehicle at a

permanent checkpoint located on a major highway away from the Mexican border for brief questioning of the vehicle's occu- pants is consistent with the Fourth Amendment, and the stops and questioning may be made at reasonably located checkpoints in the absence of any individualized suspicion that the particular vehicle contains illegal aliens. Pp. 556-564.

(a) To require that such stops always be based on reason- able suspicion would be impractical because the flow of traffic tends to be too heavy to allow the particularized study of a given car necessary to identify it as a possible carrier of illegal aliens. Such a requirement also would largely eliminate any deterrent to the conduct of well-disguised smuggling operations, even though smugglers are known to use these highways regularly.

Pp. 556-557.

(b) While the need to make routine checkpoint stops is great, the consequent intrusion on Fourth Amendment interests is quite limited, the interference with legitimate traffic being minimal and checkpoint operations involving less discretionary enforcement activity than roving-patrol stops. Pp. 557-560.

(c) Under the circumstances of these checkpoint stops, which do not involve searches, the Government or public interest in making such stops outweighs the constitutionally protected inter- est of the private citizen. Pp. 560-562.

(d) With respect to the checkpoint involved in No. 74-1560, it is constitutional to refer motorists selectively to a secondary inspection area for limited inquiry on the basis of criteria that would not sustain a roving-patrol stop, since the intrusion is sufficiently minimal that no particularized reason need exist to justify it. Pp. 563-564.

2. Operation of a fixed checkpoint need not be authorized in

advance by a judicial warrant. Camara v. Municipal Court, 387 *Together with No. 75-5387, Sifuentes v. United States, on cer-

tiorari to the United States Court of Appeals for the Fifth Circuit.

Syllabus

U. S. 523, distinguished. The visible manifestations of the field

officers' authority at a checkpoint provide assurances to motorists that the officers are acting lawfully. Moreover, the purpose of a warrant in preventing hindsight from coloring the evaluation of the reasonableness of a search or seizure is inapplicable here, since the reasonableness of checkpoint stops turns on factors such as the checkpoint's location and method of operation. These factors are not susceptible of the distortion of hindsight, and will be open to post-stop review notwithstanding the absence of a warrant. Nor is the purpose of a warrant in substituting a magistrate's judgment for that of the searching or seizing officer applicable, since the need for this is reduced when the decision to "seize" is not entirely in the hands of the field officer and deference is to be given to the administrative decisions of higher ranking officials in selecting the checkpoint locations. Pp. 564- 566.

No. 74-1560, 514 F. 2d 308, reversed and remanded; No. 75-5387, affirmed.

POWELL, J., delivered the opinion of the Court, in which BURGER,

JJ., joined. BRENNAN, J., filed a dissenting opinion, in which MAR- SHALL, J., joined, post, p. 567.

Mark L. Evans argued the cause for the United States in both cases. With him on the briefs were Solicitor General Bork, Assistant Attorney General Thornburgh, and Sidney M. Glazer.

Ballard Bennett, by appointment of the Court, 423

U. S. 1030, argued the cause and filed briefs for peti-

tioner in No. 75-5387.

Charles M. Sevilla, by appointment of the Court, 423

U. S. 922, argued the cause for respondents in No. 74-

1560. With him on the brief was Michael J. McCabe.t tMdlvin L. Wulf, Joel M. Gora, Vilma S. Martinez, Sanford J.

Rosen, and Jerome B. Falk, Jr., filed a brief for the American Civil Liberties Union et al. as amici curiae urging affirmance in No. 74-1560.

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court MR. JUSTICE POWELL delivered the opinion of the Court.

In each incompatible with

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 interna- tional border with Mexico, and each sought the exclusion of certain evidence on the ground that the operation of the checkpoint was the Fourth Amendment. 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 immigra- tion 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 pre- viously have described the checkpoint as follows:

"'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

Opinion of the Court

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. OF- FICERS." 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 offi- cial 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).

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.'

Most motorists are allowed to resume their progress with- out 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 oc- cupants are asked about their citizenship and immigra- tion status. The Government informs us that at San

1 The parties disagree as to whether vehicles not referred to the secondary inspection area are brought to a complete halt or merely "roll" slowly through the checkpoint. Resolution of this dispute is not necessary here, as we may assume, arguendo, that all motor- ists passing through the checkpoint are so slowed as to have been "seized."

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

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 second- ary inspection area could be based on something suspi- cious about a particular car passing through the check- point, 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 au- thorized the Border Patrol to conduct a routine-stop operation at the San Clemente location.'

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 pro- duced 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

2The record does not reveal explicitly why a warrant was sought. Shortly before the warrant application, however, the Court of Appeals for the Ninth Circuit had held unconstitutional a rou- tine stop and search conducted at a permanent checkpoint without such a warrant. See United States v. Bowen, 500 F. 2d 960 (1974), aff'd on other grounds, 422 U. S. 916 (1975); United States v.

Juarez-Rodriguez, 498 F. 2d 7 (1974). Soon after the warrant issued, the Court of Appeals also held unconstitutional routine checkpoint stops conducted without a warrant. See United States v. Esquer- Rivera, 500 F. 2d 313 (1974).

See also n. 15, infra.

Opinion of the Court

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.3 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 pre- arrangement in San Ysidro after the latter had been smuggled across the border. Questioning at the second- ary 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 Me- drano-Barragan approached the checkpoint with Guillen driving and Medrano-Barragan and his wife as passen- gers. Questioning at the secondary inspection area re- vealed 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 trans-

3 Each of the defendants in No. 74-1560 and the defendant in No. 75-5387 sought to suppress, among other things, the testimony of one or more illegal aliens. We noted in United States v. Brig- noni-Ponce, 422 U. S. 873, 876 n. 2 (1975), that "[t]here may be room to question whether voluntary testimony of a witness at trial, as opposed to a Government agent's testimony about objects seized or statements overheard, ." The question again is not before us.

is subject to suppression .

.

.

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

porting 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.4 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 con- sistent with the Fourth Amendment.' The Court of Ap- peals 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 ar- rested 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 Browns-

4 The prosecution of Martinez-Fuerte was before a different Dis- trict Judge than were the other cases.

the checkpoint was operating when

5 The principal question before the Court of Appeals was the constitutional significance of the "warrant of inspection" under which the defendants were stopped. See n. 15, infra. The Government, however, preserved the question whether routine checkpoint stops could be made absent a warrant.

Opinion of the Court

the checkpoint is operated differently

ville, and 65-90 miles from the nearest points of the Mexican border. The physical arrangement of the checkpoint resembles generally that at San Clemente, that but the officers customarily stop all northbound motor- ists for a brief inquiry. Motorists whom the officers inhabitants, however, are waved recognize as through the checkpoint without inquiry. Unlike the San Clemente checkpoint the Sarita operation was con- ducted without a judicial warrant.

local in

Sifuentes drove up to the checkpoint without any visible passengers. When an agent approached the ve- hicle, 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 de- nied and he was convicted after a jury trial. Sifuentes renewed his Fourth Amendment argument on appeal, contending primarily that stops made without rea- son 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.

6 We initially granted the Government's petition for a writ of certiorari in No. 74-1560, 423 U. S. 822, and later granted Sifuentes'

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

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 turn- ing to the constitutional question, we examine the con- text 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 accom- modated 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) 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.

(footnote omitted).

petition in No. 75-5387 and directed that the cases be argued in tandem. 423 U. S. 945. Subsequently we granted the motion of the Solicitor General to consolidate the cases for oral argument.

Opinion of the Court

Interdicting the flow of illegal entrants from Mexico poses formidable law enforcement problems. The prin- Id., at cipal problem arises from surreptitious entries.

405. The United States shares a border with Mex-

ico 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 per- sonnel, electronic equipment, and fences along portions of the border, it remains relatively easy for individuals It also is to enter the United States without detection. 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.' Once within the country, the aliens seek to travel inland to areas where employ- ment 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.

in an effort

The Border Patrol conducts three kinds of inland to minimize traffic-checking operations 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 to avoid circumvention by smugglers and designed others who transport the illegal aliens. Temporary checkpoints, which operate like permanent ones, occa- locations. sionally are established Finally, roving patrols are maintained to supplement the See Almeida-Sanchez v. United checkpoint system.

in other strategic

7 The latter occurs particularly where "border passes" are issued interrelated American and Mexican to simplify passage between communities along the border. These passes authorize travel within 25 miles of the border for a 72-hour period. See 8 CFR § 212.6 (1976).

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court States, 413 U. S. 266, 268 (1973).'

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 ap- prehended approximately 55,300 more deportable aliens.'

Most of the traffic-checking apprehensions were at check- points, 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 num- ber of factors. The Border Patrol believes that to as- sure 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 (iv) on a stretch of highway compatible with safe operation, and (v) beyond the 25-mile zone in which "border passes," see n. 7, supra, are valid. United States v. Baca, supra, at 406.

the checkpoint,

1 All these operations are conducted pursuant to statutory author- izations empowering Border Patrol agents to interrogate those be- lieved to be aliens as to their right to be in the United States and to inspect vehicles for aliens. 8 U. S. C. §§ 1357 (a)(1), (a)(3).

Under current regulations the authority conferred by § 1357 (a) (3) may be exercised anywhere within 100 air miles of the border. 8 CFR § 287.1 (a) (1976).

9 As used in these statistics, the term "deportable alien" means "a person who has been found to be deportable by an immigration judge, or who admits his deportability upon questioning by official agents." United States v. Baca, 368 F. Supp. 398, 404 (SD Cal.

1973). Most illegal aliens are simply deported without prosecution.

The Government routinely prosecutes persons thought to be smug- glers, many of whom are lawfully in the United States.

Opinion of the Court

involved the arrests

The record in No. 74-1560 provides a rather complete picture of the effectiveness of the San Clemente check- point. Approximately 10 million cars pass the checkpoint location each year, although the checkpoint actually is in operation only about 70% of the time."° In calendar year 1973, approximately 17,000 illegal aliens were apprehended there. During an eight-day period in 1974 that included in No. 74-1560, roughly 146,000 vehicles passed through the checkpoint during 124% hours of operation. Of these, 820 vehicles were referred to the secondary inspection area, where Border Patrol agents found 725 deportable aliens in 171 vehicles.

In all but two cases, the aliens were discovered without a conventional search of the vehicle. A similar rate of apprehensions throughout the year would have resulted in an annual total of over 33,000, although the illegal aliens pass Government contends through in No. 75-5387 does not provide comparable statistical information regarding the Sarita checkpoint. While it appears that fewer illegal aliens are apprehended there, it may be assumed that fewer pass by undetected, as every motorist is questioned.

that many the checkpoint undetected. The record

The Fourth Amendment imposes limits on search-and- seizure powers in order to prevent arbitrary and oppres- sive interference by enforcement officials with the privacy and personal security of individuals. See United States

v. Brignoni-Ponce, 422 U. S., at 878; United States v.

Ortiz, 422 U. S., at 895; Camara v. Municipal Court,

10 The Sarita checkpoint is operated a comparable proportion of time. "Down" periods are caused by personnel shortages,

the weather conditions, and-at San Clemente-peak traffic loads.

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

In delineating the constitu- tional safeguards applicable in particular contexts, the Court has weighed the public interest against the Fourth Amendment interest of the individual, United States v.

Brignoni-Ponce, supra, at 878; Terry v. Ohio, 392 U. S. 1, 20-21 (1968), a process evident in our previous cases dealing with Border Patrol traffic-checking operations.

In Almeida-Sanchez v. United States, supra, the ques- tion was whether a roving-patrol unit constitutionally could search a vehicle for illegal aliens simply because it was in the general vicinity of the border. We recognized that important law enforcement interests were at stake but held that searches by roving patrols impinged so sig- nificantly on Fourth Amendment privacy interests that a search could be conducted without consent only if there was probable cause to believe that a car contained illegal aliens, at least in the absence of a judicial warrant au- thorizing random searches by roving patrols in a given area. Compare 413 U. S., at 273, with id., at 283-285 (POWELL, J., concurring), and id., at 288 (WHITE, J., dissenting). We held in United States v. Ortiz, supra, that the same limitations applied to vehicle: searches con- ducted at a permanent checkpoint.

In United States v. Brignoni-Ponce, supra, however, we recognized that other traffic-checking practices involve a different balance of public and private interests and appropriately are subject to less stringent constitutional safeguards. The question was under what circumstances a roving patrol could stop motorists in the general area of the border for brief inquiry into their residence status. We found that the interference with Fourth Amendment interests involved in such a stop was "mod- est," 422 U. S., at 880, while the inquiry served signifi- cant law enforcement needs. We therefore held that a roving-patrol stop need not be justified by probable

Opinion of the Court

cause and may be undertaken if the stopping officer is "aware of specific articulable facts, together with ra- tional inferences from those facts, that reasonably war- rant suspicion" that a vehicle contains illegal aliens.

Id., at 884."

It is agreed that checkpoint stops are "seizures" within the meaning of the Fourth Amendment. The defend- ants contend primarily that the routine stopping of ve- hicles at a checkpoint is invalid because Brignoni-Ponce must be read as proscribing any stops in the absence of reasonable suspicion. Sifuentes alternatively contends in No. 75-5387 that routine checkpoint stops are per- missible only when the practice has the advance judicial authorization of a warrant. There was a warrant au- thorizing the stops at San Clemente but none at Sarita.

As we reach the issue of a warrant requirement only if reasonable suspicion is not required, we turn first to whether reasonable suspicion is a prerequisite to a valid stop, a question to be resolved by balancing the interests at stake.

Our previous cases have recognized that maintenance of a traffic-checking program in the interior is necessary because the flow of illegal aliens cannot be controlled effectively at the border. We note here only the sub- stantiality of the public interest in the practice of routine stops for inquiry at permanent checkpoints, a practice which the Government identifies as the most important of the traffic-checking operations. Brief for United States in No. 74-1560, pp. 19-20.12 These checkpoints

1 On the facts of the case, we concluded that the stop was im- permissible because reasonable suspicion was lacking.

12 The defendants argue at length that the public interest in is less than is asserted by the Govern-

maintaining checkpoints

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

are located on important highways; in their absence such highways would offer illegal aliens a quick and safe route into the interior. Routine checkpoint inquiries appre- hend many smugglers and illegal aliens who succumb to the lure of such highways. And the prospect of such in- quiries forces others onto less efficient roads that are less heavily traveled, slowing their movement and making them more vulnerable to detection by roving patrols. Cf.

United States v. Brignoni-Ponce, 422 U. S., at 883-885.

A requirement that stops on major routes inland always be based on reasonable suspicion would be impractical because the flow of traffic tends to be too heavy to allow the particularized study of a given car that would enable it to be identified as a possible carrier of In particular, such a requirement would largely eliminate any deterrent to the conduct of well-disguised smuggling operations, even though smugglers are known to use these highways regularly.

illegal aliens.

While the need to make routine checkpoint stops is great, the consequent intrusion on Fourth Amendment interests is quite limited. The stop does intrude to a limited extent on motorists' right to "free passage with-

ment because the flow of illegal immigrants could be reduced by means other than checkpoint operations. As one alternative they suggest legislation prohibiting the knowing employment of illegal aliens. The logic of such elaborate less-restrictive-alternative argu- ments could raise insuperable barriers to the exercise of virtually all search-and-seizure powers.

In any event, these arguments tend to go to the general proposition that all traffic-checking pro- cedures are impermissible, a premise our previous cases reject. The defendants do not suggest persuasively that the particular law en- forcement needs served by checkpoints could be met without reliance on routine checkpoint stops. Compare United States v. Brignoni- Ponce, 422 U. S., at 883 (effectiveness of roving patrols not defeated by reasonable suspicion requirement), with infra, this page.

Opinion of the Court

out interruption," Carroll v. United States, 267 U. S. 132, 154 (1925), and arguably on their right to personal secu- rity. But it involves only a brief detention of travelers during which

" '[a]ll that is required of the vehicle's occupants is a response to a brief question or two and possibly the production of a document evidencing a right to be in the United States.'" United States v. Brig- noni-Ponce, supra, at 880.

Neither the vehicle nor its occupants are searched, and visual inspection of the vehicle is limited to what can be seen without a search. This objective intrusion-the stop itself, the questioning, and the visual inspection- also existed in roving-patrol stops. But we view check- point stops in a different light because the subjective intrusion-the generating of concern or even fright on the part of lawful travelers-is appreciably less in the case of a checkpoint stop.

"[T] he circumstances surrounding a checkpoint stop and search are far less intrusive than those attend- ing a roving-patrol stop. Roving patrols often operate at night on seldom-traveled roads, and their approach may frighten motorists. At traffic check- points the motorist can see that other vehicles are being stopped, he can see visible signs of the officers' authority, and he is much less likely o be frightened or annoyed by the 422 U. S., at 894-895.

intrusion."

In Brignoni-Ponce, we recognized that Fourth Amend- ment analysis in this context also must take into account the overall degree of interference with legitimate traffic.

422 U. S., at 882-883. We concluded there that random roving-patrol stops could not be tolerated because they "would subject the residents of . . . [border] areas to

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court .

."

legitimate

potentially unlimited interference with their use of the highways, solely at the discretion of Border Patrol offi- cers. . . . [They] could stop motorists at random for questioning, day or night, anywhere within 100 air miles of the 2,000-mile border, on a city street, a busy high- way, or a desert road .

Ibid. There also . was a grave danger that such unreviewable discretion Ibid. would be abused by some officers in the field.

Routine checkpoint stops do not intrude similarly on the motoring public. First, the potential interfer- is minimal. Motorists traffic ence with using these highways are not taken by surprise as they know, or may obtain knowledge of, the location of the checkpoints and will not be stopped elsewhere. Second, checkpoint operations both appear to and actually in- volve less discretionary enforcement activity.

The in which established checkpoints regularized manner are operated to law- are duly au- abiding motorists, thorized and believed inter- to est. The location of a fixed checkpoint is not chosen by officers in the field, but by officials responsible for making overall decisions as to the most effective alloca- tion of limited enforcement resources. We may assume that such officials will be unlikely to locate a checkpoint where it bears arbitrarily or oppressively on motorists as a class. And since field officers may stop only those cars passing the checkpoint, there is less room for abusive or harassing stops of individuals than there was in the case of roving-patrol stops. Moreover, a claim that a par- ticular exercise of discretion in locating or operating a checkpoint is unreasonable is subject to post-stop judi- cial review.' 3

is visible evidence, reassuring the the public stops serve that

"3 The choice of checkpoint locations must be left largely to the discretion of Border Patrol officials, to be exercised in accordance

Opinion of the Court

The defendants arrested at the San Clemente check- point suggest that its operation involves a significant extra element of intrusiveness in that only a small per- centage of cars are referred to the secondary inspection area, thereby "stigmatizing" those diverted and reducing the assurances provided by equal treatment of all motor- ists. We think defendants overstate the consequences.

Referrals are made for the sole purpose of conducting a routine and limited inquiry into residence status that cannot feasibly be made of every motorist where the traffic is heavy. The objective intrusion of the stop and inquiry thus remains minimal. Selective referral may involve some annoyance, but it remains true that the stops should not be frightening or offensive because of their public and relatively routine nature. Moreover, selective referrals-rather than questioning the occupants of every car-tend to advance some Fourth Amendment interests by minimizing the intrusion on the general motoring public.

The defendants note correctly that to accommodate public and private in- dividualized suspicion to a constitutional search or seizure. 14 See Terry v. Ohio, 392

interests some quantum of is usually a prerequisite

with statutes and regulations that may be applicable. See n. 15, infra. Many incidents of checkpoint operation also must be com- mitted to the discretion of such officials. But see infra, at 565-566.

14 Stops for questioning, not dissimilar to those involved here, are used widely at state and local levels to enforce laws regarding drivers' licenses, safety requirements, weight limits, and similar matters. The fact that the purpose of such laws is said to be administrative is of limited relevance in weighing their intrusive- ness on one's right to travel; and the logic of the defendants' posi- tion, if realistically pursued, might prevent enforcement officials from stopping motorists for questioning on these matters in the absence of reasonable suspicion that a law was being violated. As

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Opinion of the Court

U. S., at 21, and n. 18. But the Fourth Amendment

imposes no irreducible requirement of such suspicion.

This is clear from Camara v. Municipal Court, 387 U. S.

See also Almeida-Sanchez v. United States, 523 (1967).

413 U. S., at 283-285 (POWELL, J., concurring) ; id., at 288 J., dissenting); Colonnade Catering Corp.

v. United States, 397 U. S. 72 (1970); United States v.

Biswell, 406 U. S. 311 (1972); Carroll v. United States, In Camara the Court required an 267 U. S., at 154. "area" warrant to support the reasonableness of inspect- ing private residences within a particular area for build- ing code violations, but recognized that "specific knowl- edge of the condition of the particular dwelling" was not required to enter any given residence. 387 U. S., at In so holding, the Court examined the govern- 538. ment interests advanced to justify such routine intru- sions "upon the constitutionally protected interests of the private citizen," id., at 534-535, and concluded that under the circumstances the government interests out- weighed those of the private citizen.

We think the same conclusion is appropriate here, where we deal neither with searches nor with the sanctity of private dwellings, ordinarily afforded the most stringent Fourth Amendment protection.

See, e. g., McDonald v. United States, 335 U. S.

451 (1948). As we have noted earlier, one's expecta- tion of privacy in an automobile and of freedom in its operation are significantly different from the traditional expectation of privacy and freedom in one's residence.

United States v. Ortiz, 422 U. S., at 896 n. 2; see Card- (plurality well v. Lewis, 417 U. S. 583, 590-591 (1974)

such laws are not before us, we intimate no view respecting them this practice of stopping automobiles other than to note that briefly for questioning has a long history evidencing its utility and is accepted by motorists as incident to highway use.

Opinion of the Court

opinion). And the reasonableness of the procedures fol- lowed in making these checkpoint stops makes the re- sulting intrusion on the interests of motorists minimal.

On the other hand, the purpose of the stops is legitimate and in the public interest, and the need for this enforce- ment technique is demonstrated by the records in the cases before us. Accordingly, we hold that the stops and questioning at issue may be made in the absence of located suspicion at any checkpoints.15

individualized reasonably

15 As a judicial warrant authorized the Border Patrol to make rou- tine stops at the San Clemente checkpoint, the principal question addressed by the Court of Appeals for the Ninth Circuit in No. 74- 1560 was whether routine checkpoint stops were constitutional when authorized by warrant. Cf. n. 5, supra. The Court of Appeals held alternatively that a warrant never could authorize such stops, 514

F. 2d 308, 318 (1975), and that it was unreasonable to issue a warrant

authorizing routine stops at the San Clemente location.

Id., at 321-322. the Court of Ap- peals relied on (i) "the [low] frequency with which illegal aliens pass through the San Clemente checkpoint," the distance of the checkpoint from the border, and (iii) the interference with legitimate traffic.

Ibid. We need not address these holdings spe- cifically, as we conclude that no warrant is needed. But we deem the argument by the defendants in No. 74-1560 in support of the latter holding to raise the question whether, even though a warrant is not required, it is unreasonable to locate a checkpoint at San Clemente.

latter conclusion, reaching the (ii) In

We answer this question in the negative. As indicated above, the choice of checkpoint locations is an administrative decision that must be left largely within the discretion of the Border Patrol, see n. 13, supra; cf. Camara v. Municipal Court, 387 U. S. 523, 538 (1967). We think the decision to locate a checkpoint at San Cle- mente was reasonable. The location meets the criteria prescribed by the Border Patrol to assure effectiveness, see supra, at 553, and the evidence supports the view that the needs of law enforcement are furthered by this location. The absolute number of appre- hensions at the checkpoint is high, see supra, at 554, confirming Border Patrol judgment that significant numbers of illegal aliens

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court

We further believe that it is constitutional to refer motorists selectively to the secondary inspection area at the San Clemente checkpoint on the basis of criteria that would not sustain a roving-patrol stop. Thus, even if it be assumed that such referrals are made largely on the basis of apparent Mexican ancestry, 6 we perceive no constitutional violation. Cf. United States v. Brignoni- Ponce, 422 U. S., at 885-887. As the intrusion here is suf- ficiently minimal that no particularized reason need exist to justify it, we think it follows that the Border Patrol

regularly use Interstate 5 at this point. Also, San Clemente was selected as the location where traffic is lightest between San Diego and Los Angeles, thereby minimizing interference with legitimate traffic.

No question has been raised about the reasonableness of the location of the Sarita checkpoint.

16 The Government suggests that trained Border Patrol agents rely on factors in addition to apparent Mexican ancestry when selectively diverting motorists. Brief for United States in No. 75- 5387, p. 9; see United States v. Brignoni-Ponce, 422 U. S., at 884-885.

This assertion finds support in the record. Less than 1% of the motorists passing the checkpoint are stopped for questioning, whereas American citizens of Mexican ancestry and legally resident Mexican citizens constitute a significantly larger proportion of the population of southern California. The 1970 census figures, which may not fully reflect illegal aliens, show the population of California to be .approximately 19,958,000 of whom some 3,102,000, or 16%, are Spanish-speaking or of Spanish surname. The equivalent per- centages for metropolitan San Diego and Los Angeles are 13% and respectively. U. S. Department of Commerce, 1970 Census of 18% Population, vol. 1, pt. 6, Tables 48, 140.

If the statewide population ratio is applied to the approximately 146,000 vehicles passing through the checkpoint during the eight days surrounding the arrests in No. 74-1560, roughly 23,400 would be expected to contain persons of Spanish or Mexican ancestry, yet only 820 were referred to the secondary area. This appears to refute any suggestion that the Border Patrol relies extensively on apparent Mexican ancestry standing alone in referring motorists to the secondary area.

Opinion of the Court

officers must have wide discretion in selecting the motor- ists to be diverted for the brief questioning involved. 7

Sifuentes' alternative argument is that routine stops at a checkpoint are permissible only if a warrant has given judicial authorization to the particular checkpoint location and the practice of routine stops. A warrant requirement in these circumstances draws some support from Camara, where the Court held that, absent consent, an "area" warrant was required to make a building code inspection, even though the search could be conducted absent cause to believe that there were violations in the building searched.'18

We do not think, however, that Camara is an apt

17 Of the 820 vehicles referred to the secondary inspection area dur- ing the eight days surrounding the arrests involved in No. 74-1560, roughly 20% contained illegal aliens. Supra, at 554. Thus, to the extent that the Border Patrol relies on apparent Mexican ancestry at this checkpoint, see n. 16, supra, that reliance clearly is relevant to the law enforcement need to be served. Cf. United States v.

Brignoni-Ponce, supra, at 886-887, where we noted that "[tihe like- lihood that any given person of Mexican ancestry is an alien is high . " enough although we held that apparent Mexican ancestry by itself could not create the reasonable suspicion required for a roving-patrol stop.

Different considerations would arise if, for example, reliance were put on apparent Mexican ancestry at a checkpoint operated near the Canadian border.

to make Mexican appearance a relevant factor .

.

1I There also is some support for a warrant requirement in the concurring and dissenting opinions in Almeida-Sanchez v. United States, 413 U. S. 266 (1973), which commanded the votes of five Justices. See id., at 283-285 (POWELL, J., concurring); id., at 288 (WHITE, J., dissenting). The burden of these opinions, however, was that an "area" warrant could serve as a substitute for the in- dividualized probable cause to search that otherwise was necessary to sustain roving-patrol searches. As particularized suspicion is not necessary here, the warrant function discussed in Almeida- Sanchez is not an issue in these cases.

UNITED STATES v. MARTINEZ-FUERTE 543

Opinion of the Court model.

It involved the search of private residences, for which a warrant traditionally has been required. See,

e. g., McDonald v. United States, 335 U. S. 451 (1948).

As developed more fully above, the strong Fourth Amend- ment interests that justify the warrant requirement in that context are absent here. The degree of intrusion upon privacy that may be occasioned by a search of a house hardly can be compared with the minor interfer- ence with privacy resulting from the mere stop for questioning as to residence. Moreover, the warrant requirement in Camara served specific Fourth Amend- ment interests to which a warrant requirement here would

"[W]hen [an] inspector [without a warrant] de- mands entry, the occupant has no way of knowing whether enforcement of the municipal code in- volved requires inspection of his premises, no way of knowing the lawful limits of the inspector's power to search, and no way of knowing whether the in- spector himself is acting under proper authoriza- tion." 387 U. S., at 532.

A warrant provided assurance to the occupant on these scores. We believe that the visible manifestations of the field officers' authority at a checkpoint provide sub- stantially the same assurances in this case.

the requirement Other purposes

served by of a warrant also are inapplicable here. One such pur- pose is to prevent hindsight from coloring the evaluation of the reasonableness of a search or seizure. Cf. United States v. Watson, 423 U. S. 411, 455-456, n. 22 (1976) J., dissenting). The reasonableness of

checkpoint stops, however, turns on factors such as the location and method of operation of the checkpoint, fac- tors that are not susceptible to the distortion of hindsight, and therefore will be open to post-stop review notwith-

Opinion of the Court

standing the absence of a warrant. Another purpose for a warrant requirement is to substitute the judgment of the magistrate for that of the searching or seizing officer.

United States v. United States District Court, 407 U. S.

297, 316-318 (1972). But the need for this is reduced when the decision to "seize" is not entirely in the hands of the officer in the field, and deference is to be given to the administrative decisions of higher ranking officials.

In summary, we hold that stops for brief questioning routinely conducted at permanent checkpoints are con- sistent with the Fourth Amendment and need not be au- thorized by warrant." The principal protection of Fourth

19 MR. JUSTICE BRENNAN'S dissenting opinion reflects unwarranted concern in suggesting that today's decision marks a radical new intrusion on citizens' rights: It speaks of the "evisceration of Fourth Amendment protections," and states that the Court "virtually empties the Amendment of its reasonableness requirement." Post, at 567, 568. Since 1952, Act of June 27, 1952, 66 Stat. 233, Congress has expressly authorized persons believed to be aliens to be interro- gated as to residence, and vehicles "within a reasonable distance" from the border to be searched for aliens. See n. 8, supra. The San Clemente checkpoint has been operating at or near its present location throughout the intervening 24 years. Our prior cases have limited significantly the reach of this congressional authorization, requiring probable cause for any vehicle search in the interior and reasonable suspicion for inquiry stops by roving patrols. See supra, at 555-556. Our holding today, approving routine stops for brief questioning (a type of stop familiar to all motorists) is confined to permanent checkpoints. We understand, of course, that neither longstanding congressional authorization nor widely prevailing prac- tice justifies a constitutional violation. We do suggest, however, that against this background and in the context of our recent decisions, the rhetoric of the dissent reflects unjustified concern.

"Every American citizen of Mexican ancestry and every Mexican alien lawfully in this country must know after today's decision that

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting

Amendment rights at checkpoints lies in appropriate lim- itations on the scope of the stop. See Terry v. Ohio, 392 U. S., at 24-27; United States v. Brignoni-Ponce, 422 U. S., at 881-882. We have held that checkpoint searches are constitutional only if justified by consent or probable cause to search. United States v. Ortiz, 422

U. S. 891 (1975). And our holding today is limited to

the type of stops described in this opinion. "[A]ny fur- ther detention ... must be based on consent or probable cause." United States v. Brignoni-Ponce, supra, at 882.

None of the defendants in these cases argues that the these limitations. Conse- stopping officers exceeded quently, we affirm the judgment of the Court of Appeals for the Fifth Circuit, which had affirmed the conviction of Sifuentes. We reverse the judgment of the Court of Appeals for the Ninth Circuit and remand the case with directions to affirm the conviction of Martinez-Fuerte and to remand the other cases to the District Court for further proceedings.

It is so ordered.

MR. JUSTICE BRENNAN, with whom MR. JUSTICE MAR- SHALL joins, dissenting.

Today's decision is the ninth this Term marking the continuing evisceration of Fourth Amendment protec- tions against unreasonable searches and seizures. Early in the Term, Texas v. White, 423 U. S. 67 (1975), permit- ted the warrantless search of an automobile in police custody despite the unreasonableness of the custody

he travels the fixed checkpoint highways at [his] risk .... at 572.

For the reason stated in n. 16, supra, this concern is misplaced.

Moreover, upon a proper showing, courts would not be powerless to prevent the misuse of checkpoints to harass those of Mexican ancestry.

" Post,

BRENNAN, J., dissenting

and opportunity to obtain a warrant. United States

v. Watson, 423 U. S. 411 (1976), held that regardless of

whether opportunity exists to obtain a warrant, an ar- rest in a public place for a previously committed felony never requires a warrant, a result certainly not fairly supported by either history or precedent. See id., at 433 (MARSHALL, J., dissenting). United States v. San- tana, 427 U. S. 38 (1976), went further and approved the warrantless arrest for a felony of a person stand- ing on the front porch of her residence. United States v. Miller, 425 U. S. 435 (1976), narrowed the Fourth Amendment's protection of privacy by denying the existence of a protectible interest in the compila- tion of checks, deposit slips, and other records pertaining to an individual's bank account. Stone v. Powell, ante,

p. 465, precluded the assertion of Fourth Amendment

claims in federal collateral relief proceedings. United States v. Janis, ante, p. 433, held that evidence uncon- stitutionally seized by a state officer is admissible in a civil proceeding by or against the United States. South Dakota v. Opperman, ante, p. 364, approved sweeping inventory searches of automobiles in police custody ir- respective of the particular circumstances of the case.

Finally, in Andresen v. Maryland, 427 U. S. 463 (1976), the Court, in practical effect, weakened the Fourth Amendment prohibition against general warrants.

Consistent with

this purpose to debilitate Fourth Amendment protections, the Court's decision today vir- tually empties the Amendment of its reasonableness requirement by holding that law enforcement officials manning fixed checkpoint stations who make standard- less seizures of persons do not violate the Amendment.

This holding cannot be squared with this Court's recent decisions in United States v. Ortiz, 422 U. S. 891 (1975); United States v. Brignoni-Ponce, 422 U. S. 87 (1975);

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting I dissent. the requisite and Almeida-Sanchez v. United States, 413 U. S. 266 (1973).

While justification

for permitting a search or seizure may vary in certain contexts, compare Beck v. Ohio, 379 U. S. 89 (1964), with Terry v. Ohio, 392 U. S. 1 (1968), and Camara v. Municipal Court, 387 U. S. 523 (1967), even in the exceptional situations permitting intrusions on less than probable cause, it has long been settled that justification must be measured by objective standards. Thus in the seminal decision justi- fying intrusions on less-than-probable cause, Terry v.

"The scheme of the Fourth Amendment becomes meaningful only when it is assured that at some point the conduct of those charged with enforcing the laws can be subjected to the more detached, neutral scrutiny of a judge who must evaluate the reasonableness of a particular search or seizure in light of the particular circumstances. And in mak- ing that assessment it is imperative that the facts be judged against an objective standard ....

Any- thing less would invite intrusions upon constitu- tionally guaranteed rights based on nothing more substantial than inarticulate hunches, a result this Court has consistently refused to sanction."

392

U. S., at 21-22 (emphasis added, footnote omitted).

"This demand for specificity in the information upon which police action is predicated is the central teaching of this Court's Fourth Amendment juris- prudence."

392 U. S., at 21 n. 18.

Terry thus made clear what common sense teaches: Con- duct, to be reasonable, must pass muster under objective standards applied to specific facts.

We are told today, however, that motorists without number may be individually stopped, questioned, visu-

BRENNAN, J., dissenting

intrusion by a governmental

ally inspected, and then further detained without even a showing of articulable suspicion, see ante, at 547, let alone the heretofore constitutional minimum of reason- able suspicion, a result that permits search and seizure to rest upon "nothing more substantial than inarticulate hunches." This defacement of Fourth Amendment pro- tections is arrived at by a balancing process that over- whelms the individual's protection against unwarranted official interest said to justify the search and seizure. But that method is only a convenient cover for condoning arbitrary official con- duct, for the governmental interests relied on as warrant- ing intrusion here are the same as those in Almeida- Sanchez and Ortiz, which required a showing of probable cause for roving-patrol and fixed checkpoint searches, and Brignoni-Ponce, which required at least a show- ing of reasonable suspicion based on specific articulable facts to justify roving-patrol stops. Absent some dif- ference in the nature of the intrusion, the same mini- mal requirement should be imposed for checkpoint stops.

The Court assumes, and I certainly agree, that persons stopped at fixed checkpoints, whether or not referred to a secondary detention area, are "seized" within the mean- ing of the Fourth Amendment. Moreover, since the vehicle and its occupants are subjected to a "visual in- spection," the intrusion clearly exceeds mere physical restraint, for officers are able to see more in a stopped vehicle than in vehicles traveling at normal speeds down the highway. As the Court concedes, ante, at 558, the checkpoint stop involves essentially the same intrusions as a roving-patrol stop, yet the Court provides no prin- cipled basis for distinguishing checkpoint stops.

Certainly that basis is not provided in the Court's reasoning that the subjective intrusion here is appre- ciably less than in the (ase of a stop by a roving patrol.

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting

Brignoni-Ponce nowhere bases the requirement of rea- sonable suspicion upon the subjective nature of the in- In any event, the subjective aspects of check- trusion. point stops, even if different from the subjective aspects of roving-patrol stops, just as much require some prin- cipled restraint on law enforcement conduct. The mo- torist whose conduct has been nothing but innocent- and this is overwhelmingly the case-surely resents his own detention and inspection. And checkpoints, unlike roving stops, detain thousands of motorists, a dragnet- like procedure offensive to the sensibilities of free citi- zens. Also, the delay occasioned by stopping hundreds of vehicles on a busy highway is particularly irritating.

In addition to overlooking these dimensions of sub- jective intrusion, the Court, without explanation, also ignores one major source of vexation.

In abandoning any requirement of a minimum of reasonable suspicion, or even articulable suspicion, the Court in every prac- tical sense renders meaningless, as applied to checkpoint stops, the Brignoni-Ponce holding that "standing alone [Mexican appearance] does not justify stopping all to ask if they are aliens." '1 422 Mexican-Americans

"[Mexican ancestry] alone would justify neither a reasonable belief that they were aliens, nor a reasonable belief that the car concealed other aliens who were illegally in the country. Large numbers of native-born and naturalized citizens have the physical character- istics identified with Mexican ancestry, and even in the border area a relatively small proportion of them are aliens. The likelihood that any given person of Mexican ancestry is an alien is high enough to make Mexican appearance a relevant factor, but standing alone it does not justify stopping all Mexican-Americans to ask if they are aliens." 422 U. S., at 886-887 (footnote omitted).

Today we are told that secondary referrals may be based on cri- teria that would not sustain a roving-patrol stop, and specifically that such referrals may be based largely on Mexican ancestry.

Ante, at 563. Even if the difference between Brignoni-Ponce and

BRENNAN, J., dissenting

U. S., at 887. Since the objective is almost entirely the

Mexican illegally in the country, checkpoint officials, un- inhibited by any objective standards and therefore free to stop any or all motorists without explanation or ex- cuse, wholly on whim, will perforce target motorists of Mexican appearance. The process will then inescapably discriminate against citizens of Mexican ancestry and Mexican aliens lawfully in this country for no other rea- son than that they unavoidably possess the same "sus- picious" physical and grooming characteristics of illegal Mexican aliens.

Every American citizen of Mexican ancestry and every Mexican alien lawfully in this country must know after today's decision that he travels the fixed checkpoint high- ways at the risk of being subjected not only to a stop, but also to detention and interrogation, both prolonged and to an extent far more than for non-Mexican appear- ing motorists. To be singled out for referral and to be detained and interrogated must be upsetting to any mo- torist. One wonders what actual experience supports my Brethren's conclusion that referrals "should not be fright- ening or offensive because of their public and relatively routine nature." Ante, at 560.2 In point of fact, refer-

this decision is only a matter of degree, we are not told what justifies the different treatment of Mexican appearance or why greater emphasis is permitted in the less demanding circumstances of a checkpoint. That law in this country should tolerate use of one's ancestry as probative of possible criminal conduct is repugnant under any circumstances.

2 The Court's view that "selective referrals-rather than question- ing the occupants of every car-tend to advance some Fourth Amendment interests by minimizing the intrusion on the general motoring public," ante, at. 560, stands the Fourth Amendment on its head. The starting point of this view is the unannounced assump- tion that intrusions are generally permissible; hence, any minimiza- tion of intrusions serves Fourth Amendment interests. Under the Fourth Amendment, however, the status quo is nonintrusion, for as

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting

rals, viewed in context, are not relatively routine; thou- sands are otherwise permitted to pass. But for the ar- bitrarily selected motorists who must suffer the delay and humiliation of detention and interrogation, the ex- perience can obviously be upsetting.' And that experi- ence is particularly vexing for the motorist of Mexican ancestry who is selectively referred, knowing that the officers' target is the Mexican alien. That deep resent- ment will be stirred by a sense of unfair discrimination is not difficult to foresee.4

a general matter, it is unreasonable to subject the average citizen or his property to search or seizure. Thus, minimization of intrusion only lessens the aggravation to Fourth Amendment interests; it cer- tainly does not further those interests.

3 United States v. Ortiz, 422 U. S. 891 (1975), expressly recognized that such selectivity is a source of embarrassment: "Nor do check- point procedures significantly reduce the likelihood of embarrass- ment. Motorists whose cars are searched, unlike those who are only questioned, may not be reassured by seeing that the Border Patrol searches others cars as well."

Id., at 895.

4Though today's decision would clearly permit detentions to be based solely on Mexican ancestry, the Court takes comfort in what appears to be the Border Patrol practice of not relying on Mexican ancestry standing alone in referring motorists for secondary deten- tions. Ante, at 563 n. 16. See also ante, at 566-567, n. 19. Good faith on the part of law enforcement officials, however, has never sufficed in this tribunal to substitute as a safeguard for personal free- doms or to remit our duty to effectuate constitutional guarantees.

Indeed, with particular regard to the Fourth Amendment, Terry v.

Ohio, 392 U. S. 1, 22 (1968), held that "simple '"good faith on the part of the arresting officer is not enough." . . . If subjective good faith alone were the test, the protections of the Fourth Amendment would evaporate, and the people would be "secure in their persons, houses, papers, and effects," only in the discretion of the police.'

Beck v. Ohio, [379 U. S. 89,] 97 [1964]."

Even if good faith is assumed, the affront to the dignity of Ameri- can citizens of Mexican ancestry and Mexican aliens lawfully within the country is in no way diminished. The fact still remains that people of Mexican ancestry are targeted for examination at

BRENNAN, J., dissenting

In short, if a balancing process is required, the balance should be struck, as in Brignoni-Ponce, to require that Border Patrol officers act upon at least reasonable suspi- cion in making checkpoint stops.

In any event, even if a different balance were struck, the Court cannot, with- out ignoring the Fourth Amendment requirement of rea- sonableness, justify wholly unguided seizures by officials manning the checkpoints. The Court argues, however, that practicalities necessitate otherwise: "A requirement that stops on major routes inland always be based on reasonable suspicion would be impractical because the flow of traffic tends to be too heavy to allow the particu- larized study of a given car that would enable it to be identified as a possible carrier of illegal aliens." Ante, at 557.

As an initial matter, whatever force this argument may have, it cannot apply to the secondary detentions that occurred in No. 74-1560. Once a vehicle has been slowed and observed at a checkpoint, ample opportunity

checkpoints and that the burden of checkpoint intrusions will lie heaviest on them. That, as the Court observes, ante, at 563 n. 16, "[1]ess than 1% of the motorists passing the checkpoint are stopped for questioning," whereas approximately 16% of the population of California is Spanish-speaking or of Spanish surname, has little bearing on this point-or, for that matter, on the integrity of Border Patrol practices. There is no indication how many of the 16% have physical and grooming characteristics identifiable as Mexican. There is no indication what portion of the motoring public in California is of Spanish or Mexican ancestry. Given the socioeconomic status of this portion, it is likely that the figure is significantly less than 16%. Neither is there any indica- tion that those of Mexican ancestry are not subjected to lengthier initial stops than others, even if they are not secondarily detained.

Finally, there is no indication of the ancestral makeup of the 1% who are referred for secondary detention. If, as is quite likely the case, it the sense of discrimination which will be felt is only enhanced.

is overwhelmingly Mexican,

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting

exists to formulate the reasonable suspicion which, if it actually exists, would justify further detention.

Indeed, though permitting roving stops based on reasonable sus- picion, Brignoni-Ponce required that "any further deten- tion or search must be based on [the greater showing of] consent or probable cause."

422 U. S., at 882. The Court today, however, does not impose a requirement of even reasonable suspicion for these secondary stops.

The Court's rationale is also not persuasive because several of the factors upon which officers may rely in establishing reasonable suspicion are readily ascertain- able, regardless of the flow of traffic. For example, with checkpoint stops as with roving-patrol stops, "[a]spects of the vehicle itself may justify suspicion."

Id., at 885. Thus it is relevant that the vehicle is a certain type of station wagon, appears to be heavily loaded, contains an extraordinary number of persons, or contains persons trying to hide. See ibid. If such fac- tors are satisfactory to permit the imposition of a rea- sonable-suspicion requirement in the more demanding circumstances of a roving patrol, where officers initially deal with a vehicle traveling, not at a crawl, but at highway speeds, they clearly should suffice in the cir- cumstances of a checkpoint stop.

Finally, the Court's argument fails for more basic reasons. There is no principle in the jurisprudence of fundamental rights which permits constitutional limita- tions to be dispensed with merely because they cannot be conveniently satisfied. Dispensing with reasonable suspicion as a prerequisite to stopping and inspecting motorists because the inconvenience of such a require- ment would make it impossible to identify a given car as a possible carrier of aliens is no more justifiable than dispensing with probable cause as prerequisite to the search of an individual because the inconvenience of

BRENNAN, J., dissenting

such a requirement would make it impossible to identify a given person in a high-crime area as a possible carrier of concealed weapons.

"The needs of law enforcement stand in constant tension with the Constitution's protec- tions of the individual against certain exercises of official power.

It is precisely the predictability of these pres- sures that counsels a resolute loyalty to constitutional safeguards."

Almeida-Sanchez v. United States, 413

U. S., at 273.

The Court also attempts to justify its approval of standardless conduct on the ground that checkpoint stops "involve less discretionary enforcement activity" than roving stops. Ante, at 559. This view is at odds with its later more revealing statement that "officers must have wide discretion in selecting the motorists to be diverted for the brief questioning involved." Ante, at 564. Simi- larly unpersuasive is the statement that "since field offi- cers may stop only those cars passing the checkpoint, there is less room for abusive or harassing stops of in- dividuals than there was in the case of roving-patrol stops." Ante, at 559.5 The Fourth Amendment stand-

this observation 5 As an empirical proposition,

is hardly self- evident. No small number of vehicles pass through a checkpoint.

Indeed, better than 1,000 pass through the San Clemente check- point during each hour of operation. Ante, at 554. Thus there is clearly abundant opportunity for abuse and harassment at check- points through lengthier detention and questioning of some individ- uals or arbitrary secondary detentions. Such practices need not be confined to those of Mexican ancestry. And given that it is easier to deal with a vehicle which has already been slowed than it is to observe and then chase and apprehend a vehicle travelling at highway speeds, if anything, there is more, not less, room for abuse or harassment at checkpoints.

Indeed, in Ortiz, the Court was "not persuaded that the checkpoint limits to any meaningful extent the officer's discretion to select cars for search." 422 U. S., at 895. A fortiori, discretion can be no more limited simply because the ac- tivity is detention or questioning rather than searching.

UNITED STATES v. MARTINEZ-FUERTE 543

BRENNAN, J., dissenting

ard of reasonableness admits of neither intrusion at the discretion of law enforcement personnel nor abusive or harassing stops, however infrequent. Action based merely on whatever may pique the curiosity of a par- ticular officer is the antithesis of the objective standards requisite to reasonable conduct and to avoiding abuse and harassment. Such action, which the Court now permits, has expressly been condemned as contrary to basic Fourth Amendment principles. Certainly today's holding is far removed from the proposition emphati- cally affirmed in United States v. United States District Court, 407 U. S. 297, 317 (1972), that "those charged with ... investigative and prosecutorial duty should not be the sole judges of when to utilize constitutionally sensitive means in pursuing their tasks. The historical judgment, which the Fourth Amendment accepts, is that unreviewed executive discretion may yield too readily to pressures to obtain incriminating evidence and overlook potential invasions of privacy . .

. ." Indeed, it is far removed from the even more recent affirmation that "the central concern of the Fourth Amendment is to protect liberty and privacy from arbitrary and oppressive inter- ference by government officials." United States v. Ortiz, 422 U. S., at 895.6

6 Camara v. Municipal Court, 387 U. S. 523 (1967), does not

support the Court's result. Contrary to the Court's characteriza- tion, ante, at 561, the searches condoned there were not "routine intrusions." The Court required that administrative searches pro- to reasonable standards satisfied with respect to ceed according each particular dwelling searched. 387 U. S., at 538. The search of any dwelling at the whim of administrative personnel was not permitted. The Court, however, imposes no such standards today.

Instead, any vehicle and its passengers are subject to detention at a fixed checkpoint, and "no particularized reason need exist to justify" the detention. Ante, at 563. To paraphrase an apposite observation by the Court in Almeida-Sanchez v. United States, 413 thus embodied precisely the

U. S. 266, 270 (1973), "[checkpoints]

BRENNAN, J., dissenting

The cornerstone of this society, indeed of any free society, is orderly procedure. The Constitution, as originally adopted, was therefore, in great measure, a procedural document. For the same reasons the drafters of the Bill of Rights largely placed their faith in proce- dural limitations on government action. The Fourth Amendment's requirement that searches and seizures be reasonable enforces this fundamental understanding in erecting its buffer against the arbitrary treatment of cit- izens by government. But to permit, as the Court does today, police discretion to supplant the objectivity of rea- son and, thereby, expediency to reign in the place of order, is to undermine Fourth Amendment safeguards and threaten erosion of the cornerstone of our system of a government, for, as Mr. Justice Frankfurter re- minded us, "[t]he history of American freedom is, in no small measure, the history of procedure." Malinski v.

New York, 324 U. S. 401,414 (1945).

evil the Court saw in Camara when it insisted that the 'discretion of the official in the field' be circumscribed . ..."