Protecting the U.S. Perimeter: Border Searches
Under the Fourth Amendment
Yule Kim
Legislative Attorney
June 29, 2009
Congressional Research Service
7-5700
www.crs.gov
RL31826
CRS Report for Congress
P
repared for Members and Committees of Congress

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Protecting the U.S. Perimeter: Border Searches Under the Fourth Amendment

Summary
The Fourth Amendment requires that a search or seizure conducted by a governmental agent be
reasonable and supported by probable cause. The Supreme Court has interpreted the Fourth
Amendment to include a presumptive warrant requirement on all searches and seizures conducted
by the government. Any violation of these requirements could result in the suppression of any
information derived therefrom. The Supreme Court, however, has also recognized situations that
render obtaining a warrant impractical or against the public’s interest and has accordingly crafted
various exceptions to the warrant and probable cause requirements of the Fourth Amendment.
Few exceptions to the presumptive warrant and probable cause requirements are more firmly
rooted than the “border search” exception. Derived from the sovereign right to stop and examine
persons and property crossing into the country, border searches allow customs officials the
flexibility to inspect incoming individuals and their belongings and to interdict incoming
contraband without having to inform a magistrate before the search.
Border searches can also occur in places other than the actual physical border. Two different legal
concepts authorize such searches: (1) searches at the functional equivalent of the border; and (2)
extended border searches. These concepts allow federal officers to conduct border searches even
in situations when it is not feasible to conduct the search at the actual point of entry (e.g.,
examining a person upon arrival at a U.S. airport rather than during a mid-flight crossing into the
country).
Courts have determined that border searches usually fall into two categories—routine and non-
routine—though this analysis may no longer apply to searches of vehicles or personal property.
Generally, the distinction between “routine” and “non-routine” turns on the level of intrusiveness.
Routine border searches are reasonable simply by virtue of the fact that they occur at the border
and consist of only a limited intrusion, while non-routine searches generally require “reasonable
suspicion” and vary in technique and intrusiveness.
This report first outlines the statutes authorizing certain federal officers to conduct warrantless
searches: 19 U.S.C. § 482 for customs officials and Immigration and Nationality Act (INA) § 287
(codified in 8 U.S.C. § 1357) for immigration officers. It then addresses the scope of the
government’s constitutional authority to search and seize persons and property at the border. It
also describes the varying levels of suspicion generally required for each type of border search as
interpreted by the courts. Finally, this report lists several bills before the 111th Congress that
address border searches: two of which, H.R. 239 (the Securing our Borders and our Data Act of
2009) and H.R. 1726 (the Border Security Search Accountability Act of 2009), address border
searches of laptops and other electronic storage devices. H.R. 1900 would provide emergency
deployments of federal officers to the border and would authorize funds to local law enforcement
to stem the illegal trafficking of firearms into Mexico. S. 205, H.R. 495, and H.R. 1448 would
also authorize funds for Bureau of Alcohol, Tobacco, Firearms, and Explosives agents to interdict
the illegal trafficking of firearms to Mexico.
This report does not address interior searches and seizures performed by immigration personnel
since they are not traditional “border searches.”

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Protecting the U.S. Perimeter: Border Searches Under the Fourth Amendment

Contents
Introduction ................................................................................................................................ 1
Statutory Authorization to Conduct Border Searches ................................................................... 2
Customs Officials.................................................................................................................. 2
Immigration Officers............................................................................................................. 3
The Fourth Amendment .............................................................................................................. 4
Searches................................................................................................................................ 5
Seizures ................................................................................................................................ 5
Reasonableness ..................................................................................................................... 6
The Definition of “Border” ......................................................................................................... 6
Functional Equivalent of the Border ...................................................................................... 7
Extended Border Search........................................................................................................ 8
The Distinction between the Functional Equivalent of a Border and the Extended
Border Search Doctrines .................................................................................................... 8
Types of Searches and Seizures at the Border .............................................................................. 9
Searches and Seizures of People............................................................................................ 9
Routine Searches............................................................................................................. 9
Non-Routine Searches................................................................................................... 10
Searches and Seizures of Vehicles ....................................................................................... 15
Searches of Electronic Storage Devices ............................................................................... 16
Searches of Expressive Materials ........................................................................................ 18
Legislative Action on Border Security ....................................................................................... 19

Contacts
Author Contact Information ...................................................................................................... 21
Acknowledgments .................................................................................................................... 21

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Protecting the U.S. Perimeter: Border Searches Under the Fourth Amendment

Introduction
The United States’ border policy seeks to balance the promotion of legitimate cross-border
commerce and travel with its sovereign right to protect itself from terrorist activities, unlawful
migration, and contraband. When formulating security initiatives regarding the border, officials
must ensure that their search and seizure policies comply with the Fourth Amendment, which
states: “The right of the people to be secure in their persons, houses, papers, and effects, against
unreasonable searches and seizures, shall not be violated, and no Warrants shall issue but upon
probable cause….” The Supreme Court has construed this language to impose a presumptive
warrant requirement on all searches and seizures conducted by governmental authority. However,
the Court has also recognized exceptions to the Fourth Amendment’s warrant and probable cause
requirements. One such exception is the “border search” exception. Based on the inherent
authority of a sovereign nation to regulate who and what comes within it borders, this exception
renders border searches per se reasonable under the Fourth Amendment simply because they
occur at the border. Because they are considered per se reasonable, border searches can usually be
conducted without a warrant or probable cause.
Federal courts have grouped border searches into two categories: routine and non-routine.
Routine searches usually intrude into an individual’s privacy in very limited ways. They generally
consist of document checks, patdowns, or the emptying of pockets, and do not need to be justified
by any suspicion of wrongdoing. Similarly, a government agent generally does not need suspicion
of criminal activity before he may conduct limited inspections of cars and personal property at the
border.
On the other hand, government officials may conduct certain “non-routine” searches at the border
only if they have at least a “reasonable suspicion” that the searched individual is smuggling
contraband or conducting other illegal activities. “Reasonable suspicion” means an officer has a
particularized and objective basis for suspecting the searched individual of wrongdoing.1 Certain
non-routine search procedures are perceived to intrude and have the potential to be embarrassing
or destructive. In order to prevent their excessive use, courts have held that border agents must
have at least a “reasonable suspicion” of wrongdoing before they may conduct destructive
searches of inanimate objects, prolonged detentions, strip searches, body cavity searches, X-ray
searches, and the like. Whether reasonable suspicion is required is a fact-intensive totality of the
circumstances test determined on a case-by-case basis.
Although there was some federal circuit precedent to require more than reasonable suspicion to
justify some acutely intrusive forms of non-routine border searches, the Supreme Court has since
warned against developing further gradations of suspicion beyond reasonable suspicion.2 Thus,
federal courts generally appear to apply only the reasonable suspicion standard when reviewing a
non-routine border search.
The Ninth Circuit appears to have refocused the border search analysis to presume that searches
at the border do not require reasonable suspicion. Thus, the fact-intensive analysis used to
determine whether reasonable suspicion is required may no longer be a central consideration in

1 The reasonable suspicion standard requires less suspicion of wrongdoing than probable cause, the normal standard
required for a Fourth Amendment search or seizure. See Terry v. Ohio, 392 U.S. 1, 21 (1968).
2 See infra “Non-Routine Searches.”
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analyzing border searches. Rather, the Ninth Circuit, at least, begins with the presumption that
most border searches do not require any suspicion of wrongdoing to be justified. If, however, the
case at issue involves (1) an intrusive search of the body, (2) a particularly destructive search of
property, or (3) a search conducted in a particularly offensive manner, the presumption would be
rebutted and “reasonable suspicion” would be required.
Statutory Authorization to Conduct Border Searches
Two statutory provisions confer border search powers on agents of the United States: 19 U.S.C. §
482, which allows customs officials to conduct searches of persons, vehicles, and mail at the
border; and Immigration and Nationality Act (INA) § 287, which gives immigration officers
broad powers to interrogate, detain, and search individuals and vehicles. Both statutes have been
interpreted such that these agents may conduct searches and arrests at the border without warrant
or probable cause. However, the exercise of these powers still must comport with the
requirements of the Fourth Amendment.3
Customs Officials
Section 482 of Title 19 of the U.S. Code authorizes customs officials to conduct searches for
unlawfully imported materials.4 This provision specifically confers upon those customs officials
who are authorized to board and search sea vessels the additional power to search “any vehicle,
beast, or person” where they suspect they will discover goods subject to U.S. duties or goods
whose importation is outlawed by the United States.5 Federal courts have interpreted this to mean
that customs officials are empowered to search vehicles for aliens, as well as contraband.6 A
customs official who exercises this authority to conduct a border search need not have a warrant
or probable cause.7 However, border searches must still be “reasonable” in light of the
circumstances.8
Furthermore, customs officials may also search “any trunk or envelope, wherever found,” in
which they have “reasonable cause to suspect”9 there is merchandise imported contrary to law.10
The U.S. Supreme Court has interpreted “any trunk or envelope” to include all international mail

3 Many of the nation’s border security agencies or functions have been transferred to the Department of Homeland
Security. See P.L. 107-296. When discussing case law, this report uses agency names as used in the case law, even if
the agency may no longer have responsibilities at the border.
4 Act of July 18, 1866, ch. 201, § 3, 14 Stat. 178; R.S. § 3061 (codified at 19 U.S.C. § 482).
5 19 U.S.C. § 482.
6 United States v. Rivera, 595 F.2d 1095 (5th Cir. 1979); United States v. Bilir, 592 F.2d 735 (4th Cir. 1979).
7 United States v. Glaziou, 402 F.2d 8 (2d Cir. 1968); United States v. Berard, 281 F. Supp. 328 (D. Mass. 1968).
8 United States v. Montoya de Hernandez, 473 U.S. 53, 539 (1985) (“Having presented herself at the border for
admission, and having subjected herself to the criminal enforcement powers of the Federal Government, respondent
was entitled to be free from unreasonable search and seizure.”). See also United States v. Bilir, 592 F.2d 735 (4th Cir.
1979); United States v. Bowman, 502 F.2d 1215 (1974).
9 Normally, reasonable cause is synonymous with probable cause. See Black’s Law Dictionary 1219 (7th Ed. 1999).
However, the Supreme Court interpreted “reasonable cause to suspect” to be a less stringent requirement than probable
cause. United States v. Ramsey, 431 U.S. 606, 612-13 (1977). Thus, in this context, “reasonable cause to suspect” is
more likely equivalent to “reasonable suspicion.”
10 19 U.S.C. § 482(a).
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entering the United States.11 This means customs officials need not have probable cause, nor must
they procure a warrant, to commence a search of a piece of international mail.12 However, even
though a customs official may conduct a border search of incoming international mail, the search
is still “subject to the substantive limitations imposed by the Constitution,” which is to say the
Fourth Amendment’s reasonableness requirement.13
Immigration Officers
Section 287 of the Immigration and Nationality Act (INA) expressly confers upon immigration
officers14 broad powers to question and detain individuals without warrant either at the border or
in the interior of the United States. For example, immigration officers may, without warrant,
interrogate aliens about their right to be within the United States.15
They may also conduct some searches without a warrant. The INA expressly authorizes
immigration officers, within “a reasonable distance” from the external boundary of the United
States, to search any land-based vehicle or conveyance, and any vessel within U.S. territorial
waters.16 Immigration officers can also access without warrant any private lands located within 25
miles of the U.S. border, but not dwellings, for the purpose of patrolling for aliens illegally
entering the United States.17 Moreover, the statute authorizes immigration officers to search,
without warrant, a person and the personal effects in his possession, if the person seeks admission
to the United States and the officer has reasonable cause to suspect that a search would disclose
grounds for denying admission.18
Furthermore, immigration officers may arrest without warrant:
• any alien who, in the presence of the officer, is attempting to enter the United
States in violation of the federal immigration laws;19

11 Ramsey, 431 U.S. 606.
12 Id. at 612-13.
13 Id. at 619.
14 Although the statute speaks of “immigration officers,” the Department of Homeland Security (DHS) designates by
regulation those classes of DHS agents who actually wield these powers. See 8 C.F.R. § 287.5 for a list of officers who
are authorized to wield the powers described in this section. Typically, both Border Patrol agents and Immigration and
Customs Enforcement agents are empowered to wield all of these powers.
15 INA § 287(a)(1), 8 U.S.C. § 1357(a)(1) (authorizing any officer or employee “to interrogate any alien or person
believed to be an alien as to his right to be or remain in the United States” without obtaining a warrant). See also 8
C.F.R. § 287.5 (authorizing all immigration officers to exercise this power).
16 INA § 287(a)(3), 8 U.S.C. § 1357(a)(3). This statute also authorizes searches without warrant “within a reasonable
distance from any external boundary of the United States.” Reasonable distance is defined by 8 C.F.R. § 287.1(a)(2) to
mean “within 100 air miles from any external boundary of the United States or any shorter distance which may be fixed
by the chief patrol agent of CBP, or the special agent in charge of ICE.” External boundary is defined by 8 C.F.R. §
287.1(a)(1) to mean “the land boundaries and the territorial sea of the United States extending 12 nautical miles from
the baselines of the United States determined in accordance with international law.”
17 Id.
18 INA § 287(c), 8 U.S.C. § 1357(c).
19 INA § 287(a)(2), 8 U.S.C. § 1357(a)(2) (authorizing any officer or employee “to arrest any alien who in [the
officer’s] presence or view is entering or attempting to enter the United States in violation of any law or regulation
made in pursuance of law regulating the admission, exclusion, expulsion, or removal of aliens” or “arrest any alien in
the United States, if [the officer] has reason to believe that the alien so arrested is in the United States in violation of
any such law or regulation and is likely to escape before a warrant can be obtained for his arrest”).
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• any alien who the officer has a reason to believe is an alien currently within the
United States in violation of the federal immigration laws;20
• any person for any felony regulating the admission or removal of aliens;21
• any person for any offense against the United States committed in the presence of
the officer;22 or
• any person for any felony if the officer has reasonable grounds to believe the
person committed the felony, the arrest was made while the officer was
performing duties relating to the enforcement of the federal immigration laws,
there is a likelihood that the suspect would escape before a warrant can be
obtained, and the officer is properly certified to make those types of arrests.23
Section 287 does not impose any specific limitations on any of the immigration officer’s powers
to search, interrogate, or arrest aliens without warrant.24 Nonetheless, an immigration officer’s
powers to search, interrogate, or arrest aliens without warrant are still subject to constitutional
constraints, including the Fourth Amendment requirement that all searches and seizures (i.e.,
interrogations and arrests) be reasonable.25 As discussed below, the “reasonableness” of a search,
interrogation, or arrest varies depending on the circumstances, which include the justifications for
the search, the scope, place, and manner of the search, and whether an appropriate exception to
the Fourth Amendment applies.
The Fourth Amendment
The Fourth Amendment mandates that a search or seizure conducted by a government agent must
be reasonable and that probable cause must support a warrant.26 Although the Supreme Court has
interpreted this to mean that a warrant is presumptively required along with a need for

20 Id.
21 INA § 287(a)(4), 8 U.S.C. § 1357(a)(4) (authorizing any officer or employee “to make arrests for felonies which
have been committed and which are cognizable under any law of the United States regulating the admission, exclusion,
expulsion or removal of aliens, if he has reason to believe that the person so arrested is guilty of such felony and if
there is likelihood of the person escaping before a warrant can be obtained for his arrest”).
22 INA § 287(a)(5)(A), 8 U.S.C. § 1357(a)(5)(A).
23 INA § 287(a)(5)(B), 8 U.S.C. § 1357(a)(5)(B). See also 8 C.F.R. § 287.5(c)(4).
24 See Zepeda v. INS, 753 F.2d. 719, 725-26 (9th Cir. 1983) (agreeing with the government’s argument that § 287
authorized the interrogation of aliens under the fullest extent permissible under the Fourth Amendment). See also
Babula v. INS, 665 F.2d 293 (3d Cir. 1981).
25 United States v. Brignoni-Ponce, 422 U.S. 873 (1975). See also United States v. Rogers, 436 F. Supp. 1 (E.D. Mich.
1976) (holding that the Fourth Amendment prohibits identification stops by roving patrols that are not based on
articulable suspicion of illegal activity); Illinois Migrant Council v. Pilliod, 531 F. Supp. 1011 (N.D. Ill. 1982) (holding
that the Fourth Amendment prohibits INS from conducting investigatory seizures based only on reasonable suspicion
that a person seized is an alien).
26 U.S. Const., Amend. IV.
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individualized suspicion of wrongdoing,27 the Court has also recognized “specifically established
exceptions” to the warrant and probable cause requirements of the Fourth Amendment.28
However, before taking these exceptions into consideration, a Fourth Amendment analysis begins
with this inquiry: (1) whether the government action was sufficiently intrusive to constitute a
“search” or “seizure” and (2) whether the intrusion was “reasonable” in light of the
circumstances.29
Searches
A search triggers Fourth Amendment protections when (1) the individual personally held an
expectation of privacy in the searched object or place and (2) society is willing to recognize that
expectation as reasonable.30 In order for the expectation of privacy to be deemed reasonable, there
must be some property law or social norm that signifies that the searched object or place is closed
from public intrusion.31 For example, where the government uses a remote surveillance device not
generally available for public use to explore physical activities within a “constitutionally
protected area” (e.g., a home), and that area would have been otherwise undetectable without
some sort of physical intrusion, the surveillance is a “search” and is presumptively unreasonable
without a warrant.32
Seizures
Property or individuals may be seized. The Supreme Court has described a seizure of property as
“some meaningful interference with an individual’s possessory interests in that property.”33 An
individual is “seized” when, in light of all the circumstances surrounding the incident, a
government official makes a person reasonably believe that he is not at liberty to leave the
official’s presence.34 A seizure of a person, therefore, can include full arrests, investigatory
detentions, checkpoint stops for citizenship inquiries, and detentions of a person against his will.
However, if a person consents to be interviewed by an officer, that interview is not a “seizure.”35
Detaining a suspect after a consensual interview does not violate the Fourth Amendment if,
during the course of the interview, the officer finds sufficient cause to suspect that the person

27 Katz v. United States, 389 U.S. 347, 357 (1967) (“[S]earches conducted outside the judicial process without prior
approval by judge or magistrate are per se unreasonable under the Fourth Amendment—subject only to a few
specifically established and well delineated exceptions.”).
28 Camara v. Municipal Court, 387 U.S. 523, 539-540 (1967).
29 See Walter v. United States, 447 U.S. 649, 656 (1980) (noting that a wrongful search or seizure conducted by a
private party does not violate the Fourth Amendment).
30 Katz, 389 U.S. at 361 (Harlan, J., concurring). See also Oliver v. United States, 466 U.S. 170, 177-78 (1984).
31 Minnesota v. Carter, 525 U.S. 83, 88 (1998).
32 Kyllo v. United States, 533 U.S. 27, 40 (2001).
33 Sodal v. Cook County, 506 U.S. 56, 61 (1992) quoting United States v. Jacobsen, 466 U.S. 109, 113 (1984).
34 Florida v. Bostick, 501 U.S. 429, 437 (1991) citing Michigan v. Chesternut, 486 U.S. 567, 573 (1988). See also
United States v. Mendenhall, 446 U.S. 544 (1980); Brendlin v. California, 551 U.S. 249 (2007).
35 INS v. Delgado, 466 U.S. 210, 216 (1984). See also Florida v. Royer, 460 U.S. 491 (1983) (“Interrogation relating to
one’s identity or a request for identification by the police does not, by itself, constitute a Fourth Amendment seizure.”).
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committed wrongdoing. But an officer cannot construe a person’s refusal to be interviewed as
sufficient cause to suspect wrongdoing.36
An immigration officer’s questioning of an individual illustrates how an encounter which may
appear to be a seizure is in fact not. Merely questioning an individual about his identity,
regardless of whether he is aware he can leave the officer or refuse to cooperate by not answering,
is not a seizure.37 Therefore, such questioning need not be predicated on reasonable suspicion that
the individual is an alien.38 Nonetheless, if “the circumstances are so intimidating as to
demonstrate that a reasonable person would have believed he was not free to leave if he had not
responded,” then the encounter may be deemed a seizure.39 When the interview becomes a
seizure, either through a formal arrest or when the circumstances are such that a reasonable
person would understand he could not leave, the officer must, at a minimum, have “a reasonable
suspicion, based on articulable facts, that the person being questioned is, or is attempting to be,
engaged in an offense against the United States or is an alien illegally in the United States.”40
Reasonableness
Determining whether a government action is “reasonable” requires balancing the governmental
interest justifying the intrusion against a person’s legitimate expectation of privacy. When the
government interest fails to justify its intrusion of a legitimate expectation of privacy, a violation
of the Fourth Amendment occurs. This violation may result in any evidence derived from the
unlawful search to be suppressed and excluded from a judicial proceeding. However, this
“exclusionary rule” does not generally apply in proceedings involving the removal of aliens from
the United States.41
The Definition of “Border”
Warrantless searches are per se unreasonable under the Fourth Amendment, unless an established
exception applies. The border search is a well-recognized and long established exception to the
Fourth Amendment’s probable cause and warrant requirements. In general, the border is the point
where entry into the United States is first made by land from the neighboring countries of Mexico
or Canada, at the place where a ship docks in the United States after having been to a foreign

36 Delgado, 466 U.S. at 216.
37 Id.; United States v. Rodriguez-Franco, 749 F.2d 1555, 1560 (11th Cir. 1985). See also 8 C.F.R. § 287.8(b)(1) (“An
immigration officer, like any other person, has the right to ask questions of anyone as long as the immigration officer
does not restrain the freedom of an individual, not under arrest, to walk away.”).
38 Zepeda, 753 F.2d at 731. See also Cuevas-Ortega v. INS, 588 F.2d 1274 (9th Cir. 1979); Cordon de Ruano v. INS,
588 F.2d 1274 (9th Cir. 1977).
39 Delgado, 466 U.S. at 216. See also Zepeda, 753 F.2d at 730.
40 8 C.F.R. § 287.8(b)(2).
41 INS v. Lopez-Mendoza, 468 U.S. 1032, 1046 (1984). See also Mapp v. Ohio, 367 U.S. 643, 648 (1961)
(exclusionary rule in general). But see Almeida-Amaral v. Gonzales, 461 F.3d 231, 234 (2d Cir. 2006) (“The [Supreme]
Court qualified [Lopez-Mendoza]’s ruling in two significant ways. First, it stated that its ‘conclusions concerning the
exclusionary rule’s value might change, if there developed good reason to believe that Fourth Amendment violations
by [immigration] officers were widespread.’ And, second, it explained that its holding did not necessarily pertain to
circumstances involving ‘egregious violations of Fourth Amendment or other liberties that might transgress notions of
fundamental fairness and undermine the probative value of the evidence obtained.’”).
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port, and at any airport in the country where international flights first land. Authorities at these
locations may search a person entering or leaving the country, an individual’s automobile,
baggage, or goods, and materials imported to and exported from the country.42 Authorized by the
First Congress,43 the border search exception has a history older than the Fourth Amendment and
derives from Congress’s inherent authority to regulate commerce with foreign nations and to
enforce immigration laws.44 The Fourth Amendment does not require warrants or probable cause
for most stops and searches at the border because the power to control who or what comes within
a nation’s borders is an inherent attribute of national sovereignty.45
Although border searches may generally be conducted without a warrant or probable cause, they
must still be reasonable.46 Federal courts have determined that border searches usually fall into
two categories—routine and non-routine, the distinction generally turning on the intrusiveness of
the search. Routine border searches are reasonable simply by virtue of the fact that they occur at
the border and consist of only a limited intrusion, while non-routine searches generally require
reasonable suspicion and vary in technique and intrusiveness. It should be noted, however, that
the Supreme Court has arguably suggested that the routine/non-routine analysis may no longer be
appropriate for searches of vehicles and personal property.47
Functional Equivalent of the Border
The border search exception extends to those searches conducted at the “functional equivalent” of
the border. The “functional equivalent” of a border is generally the first practical detention point
after a border crossing or the final port-of-entry.48 Places such as international airports within the
country and ports within the country’s territorial waters or stations at the intersection of two or
more roads extending from the border exemplify such functional equivalents.49
This doctrine addresses the problem posed by the impossibility of stopping an individual for
inspection who is in mid-transit when crossing the physical border. By permitting searches at the
functional equivalent of the border, the doctrine permits a search to be effected at the first
practicable location, namely the port-of-entry. The reasoning is that the port-of-entry is, much like
a border checkpoint, the place where an individual first enters the country, and thus a search for
contraband at a port-of-entry is as effective as a search at the border.50
A search at the border’s functional equivalent is constitutionally valid when: (1) a reasonable
certainty exists that the person or thing crossed the border; (2) a reasonable certainty exists that
there was no change in the object of the search since it crossed the border; and (3) the search was
conducted as soon as practicable after the border crossing.51 In general, when applying this test,

42 See supra “Statutory Authorization to Conduct Border Searches.”
43 Act of July 31, 1789, ch.5 §§ 23-24, 1 Stat. 29, 43 (current version at 19 U.S.C. §§ 482, 1582).
44 United States v. Ramsey, 431 U.S. 606, 619 (1977) (citing U.S. Const., Art. I, § 8, cl. 3).
45 See Ramsey, 431 U.S. at 616.
46 Marsh v. United States, 344 F.2d 317, 324 (5th Cir. 1965).
47 United States v. Flores-Montano, 541 U.S. 149 (2004). See infra “Searches and Seizures of Vehicles.”
48 Thirty-First Annual Review of Criminal Procedure; Border Searches, 90 Geo. L.J. 1087, 1190 (2002) (9th Cir. 1973).
49 Almeida-Sanchez v. United States, 413 U.S. 266, 272-73 (1973).
50 See United States v. Hill, 939 F.2d 934, 936 (11th Cir. 1991).
51 Id. at 937.
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courts have given the “border” a geographically flexible reading because people can enter the
country at points other than the actual border.52
Extended Border Search
The border search exception may also allow warrantless searches beyond the border or its
functional equivalent. Under the “extended border search” doctrine, government officials may
conduct a warrantless search beyond the border or its functional equivalent if (1) the government
officials have a reasonable certainty53 that a border was crossed or there exists a “high degree of
probability” that a border was crossed; (2) they also have reasonable certainty that no change in
the object of the search has occurred between the time of the border crossing and the search; and
(3) they have “reasonable suspicion” that criminal activity was occurring.54 This three-part test
ensures that a significant temporal nexus still exists between the search and the suspect’s border
crossing.55
The extended border search doctrine has gained wide acceptance among the federal courts
because they deem that it strikes a sensible balance between the legitimate privacy interests of the
individual and the societal interests in the enforcement of border security laws.56
The Distinction between the Functional Equivalent of a Border and
the Extended Border Search Doctrines
Although a search at the border’s functional equivalent and an extended border search require
similar elements, the extended border search entails a potentially greater intrusion on a legitimate
expectation of privacy. Thus, an extended border search always requires a showing of “reasonable
suspicion” of criminal activity, while a search at the functional equivalent of the border may not
require any degree of suspicion whatsoever.
Another difference is that an extended border search takes place after the first point in time when
an individual might have been stopped within the country.57 For example, in United States v. Teng
Yang, the Seventh Circuit upheld an extended border search that occurred at an international
airport but after the defendant had already undergone an initial inspection at the designated U.S.
border inspection site.58 The court determined that “[i]t is the enforcement of the customs laws

52 Id. at 936 (“Because people can enter the country at points other than along the actual border, courts look to whether
the point of entry is the functional equivalent of the border. Places such as international airports within the country and
ports within the country’s territorial waters exemplify such functional equivalents.”).
53 Reasonable certainty, in the context of this test, has been defined as a standard which requires more than probable
cause, but less than proof beyond a reasonable doubt. United States v. Cardenas, 9 F.3d 1139, 1148 (5th Cir. 1993).
54 See, e.g., United States v. Delgado 810 F.2d 480, 482 (5th Cir. 1987). In Delgado, smugglers used a foot-bridge to
transfer narcotics to delivery trucks on a farm near El Paso, Texas. The court upheld an extended border search
conducted on a farm road near and leading from the border, but not at the official border checkpoint.
55 United States v. Teng Yang, 286 F.3d. 940, 946 (7th Cir. 2002).
56 See, e.g., Teng Yang, 286 F.3d. 940; United States v. Sahanaja, 430 F.3d 1049 (9th Cir. 2005); United States v.
Espinoza-Seanez, 862 F.2d 526 (5th Cir. 1989); United States v. Caicedo-Guarnizo, 723 F.2d 1420 (9th Cir. 1984);
United States v. Garcia, 672 F.2d 1349 (11th Cir. 1982); United States v. Bilir, 592 F.2d 735 (4th Cir. 1979).
57 United States v. Niver, 689 F.2d 520, 526 (5th Cir. 1982).
58 286 F.3d. 940 (7th Cir. 2002).
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combined with the mandate of protecting the border of the United States that permits the
extension of the search rights of border authorities to allow non-routine searches in areas near our
nation’s borders.”59
Types of Searches and Seizures at the Border
Courts have historically analyzed border searches based on whether they are “routine” or “non-
routine.” However, this type of division may no longer be appropriate for vehicular searches. And
at least one court appears to have extended this analysis to searches of electronic storage devices
and other containers.
The following sections examine how federal courts generally analyze border searches of persons,
vehicles, and electronic storage devices.
Searches and Seizures of People
Routine Searches
In order to regulate the collection of duties and to prevent the introduction of illegal aliens and
contraband into this country, Congress has granted the authority to conduct routine searches of
persons and their personal belongings at the border without reasonable suspicion, probable cause,
or a warrant.60 A routine border search is a search that does not pose a serious invasion of privacy
or offend the average traveler.61 For example, a routine border search may consist of limited
searches for contraband or weapons through a pat-down;62 the removal of outer garments such as
jackets, hats, or shoes, the emptying of pockets, wallets, or purses;63 the use of a drug-sniffing
dog;64 the examination of outbound materials;65 and the inspection of luggage.66

59 Id. at 947.
60 See, e.g., 8 U.S.C. § 1357(c) (authorizing immigration officials to search without a warrant persons entering the
country for evidence which may lead to the individual’s exclusion); 19 U.S.C. § 1496 (authorizing customs officials to
search the baggage of person entering the country); 19 U.S.C. § 1582 (authorizing customs officials to detain and
search all persons coming into the United States from foreign countries). See also United States v. Montoya de
Hernandez, 473 U.S. 531, 538 (1985).
61 United States v. Johnson, 991 F.2d 1287, 1291 (7th Cir. 1993).
62 See, e.g., United States v. Beras, 183 F.3d 22, 24 (1st Cir. 1999) (holding that a patdown of an international traveler’s
legs was not intrusive enough to qualify as non-routine).
63 United States v. Sandler, 644 F.2d 1163, 1169 (5th Cir. 1981).
64 United States v. Kelly, 302 F.3d 291, 294-95 (5th Cir. 2002) (sniff by a dog of a person at the border upheld as a
routine border search); cf. United States v. Garcia-Garcia, 319 F.3d 726, 730 (5th Cir. 2003) (dog sniff of a person on a
bus at an immigration checkpoint upheld and seen as analogous to a pat down).
65 United States v. Kolawole Odutayo, 406 F.3d 386, 392 (5th Cir. 2005) (joining sister circuits in holding that the
border search exception applies for all outgoing searches at the border).
66 United States v. Okafor, 285 F.3d 842 (9th Cir. 2002) (finding an X-ray examination and subsequent probe of luggage
a routine search because it requires no force, poses no risk to the bag’s owner or to the public, causes no psychological
fear, and does not harm the baggage); United States v. Lawson, 461 F.3d 697, 701 (6th Cir. 2006) (accepting the
“commonsense conclusion that customs officers may x-ray an airline passenger’s luggage at the border without
reasonable suspicion”).
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It has long been established that border crossers’ reasonable expectation of privacy is lower at the
border because they generally expect border guards to search persons and property for
contraband. Because this is common knowledge, border crossers are put on notice when
approaching a border that a search may be imminent, and thus their privacy is “less invaded by
[border] searches” when they occur.67 Thus, routine searches do not violate the Fourth
Amendment simply because they occur at the border.68 Moreover, courts consider routine border
searches to be permissible because they are administered to a class of people (international
travelers) and are not used to target individuals.69
There is no established test that determines whether a particular search procedure is routine.
However, the degree of intrusiveness or invasiveness associated with the particular technique is
especially indicative of whether a search is routine. The First Circuit, for example, compiled a
nonexhaustive list of six factors to be considered: (1) whether the search required the suspect to
disrobe or expose any intimate body parts; (2) whether physical contact was made with the
suspect during the search; (3) whether force was used; (4) whether the type of search exposed the
suspect to pain or danger; (5) the overall manner in which the search was conducted; and (6)
whether the suspect’s reasonable expectations of privacy, if any, were abrogated by the search.70
Non-Routine Searches
Once a search of a person’s body goes beyond a limited intrusion, a court may determine that a
non-routine search has occurred. Non-routine border searches may include prolonged detentions,
strip searches, body cavity searches, and some X-ray examinations.71 Destructive searches of
property can also qualify as non-routine.
At the very least, it appears courts require a government official to have a “reasonable suspicion”
of illegal activity to conduct a non-routine border search.72 The reasonable suspicion standard
generally requires an officer at the border to have “a particularized and objective basis for

67 Gary N. Jacobs, Note, Border Searches and the Fourth Amendment, 77 Yale L.J. 1007, 1012 (1968). It should also
be noted that the “reasonable person” test presupposes an innocent person who has nothing to conceal from customs.
Bostick, 501 U.S. at 437.
68 United States v. Odland, 502 F.2d 148 (7th Cir. 1974) citing Carroll v. United States, 267 U.S. 132, 153 (1925). Some
courts have indicated a need for “mere suspicion” to conduct a routine border search, which usually requires at least
some knowledge identifying an individual as a suspect. See, e.g., Rodriguez-Gonzalez v. United States, 378 F.2d 256
(9th Cir. 1967) (also using the term unsupported suspicion). This standard, however, is an inaccurate articulation of the
general rule that no suspicion is required. See Odland, 502 F.2d at 151 (“Any person or thing coming into the United
States is subject to search by that fact alone, whether or not there be any suspicion of illegality directed to the particular
person or thing to be searched.”); Bradley v. United States, 299 F.3d 197, n.7 (3d Cir. 2002) (stating “mere suspicion”
standard effectively overruled by Montoya de Hernandez).
69 77 Yale L.J. 1007, 1012 (1968).
70 United States v. Braks, 842 F.2d 509, 511-12 (1st Cir. 1988). The Braks court concluded that only strip searches and
body cavity searches are consistently non-routine.
71 See, e.g., United States v. Reyes, 821 F.2d 168, 170-71 (2d Cir. 1987) (strip search); United States v. Oyekan, 786
F.2d 832, 837 (8th Cir. 1986) (strip search); United States v. Adekunle, 2 F.3d 559, 562 (5th Cir. 1993) (continued
detention and X-ray examination of alimentary canal); United States v. Rivas, 157 F.3d 364, 367 (5th Cir. 1998)
(drilling of hole into body of automobile).
72 Montoya de Hernandez, 473 U.S. at 541; United States v. Garcia-Garcia, 319 F.3d 726, 730 (5th Cir. 2003) (an alert
by a drug sniffing dog provided reasonable suspicion to detain a bus long enough to investigate the reason for the dog’s
response).
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suspecting the particular person” of wrongdoing.73 For example, in United States v. Forbicetta,
the court found reasonable suspicion to exist where Customs officials acted on the following
objective facts: the suspect (1) arrived from Bogota, Colombia, (2) was traveling alone, (3) had
only one suitcase and no items requiring Customs inspection, (4) was young, clean-looking, and
attractive, and (5) was wearing a loose-fitting dress.74 These factors taken together matched the
“smuggling profile” for narcotic carriers in that area, and thus, the court concluded there was a
sufficient basis to conduct the search.
The Supreme Court has not enumerated the factors that should be considered when determining
whether a border search is routine or non-routine.75 This task has generally been left to lower
federal courts. However, in United States v. Montoya de Hernandez, the Supreme Court
concluded that one such standard, a “clear indication” of suspicion (i.e., a suggestion that is free
from doubt), was not required by the Fourth Amendment to justify a prolonged detention in an
airport.76 The Court determined that the use of the term “clear indication” in its past jurisprudence
was only meant to indicate the necessity for particularized suspicion, “rather than as enunciating a
third Fourth Amendment threshold between ‘reasonable suspicion’ and ‘probable cause.’”77
Federal courts now view the Montoya de Hernandez reasoning as both a warning against using
suspicion standards other than reasonable suspicion for non-routine border searches and a specific
disavowal of the use of the “clear indication” standard when analyzing a border search.78
Although some courts had previously required a “clear indication” to justify especially intrusive
border searches other than prolonged detentions,79 courts generally construe the disavowal of this
standard in Montoya de Hernandez to apply to other invasive border searches. “Reasonable
suspicion” is the standard used to justify non-routine searches.
Prolonged Detentions
Prolonged detentions may be conducted in order to verify or dispel an agent’s suspicion that a
traveler has committed wrongdoing. In Montoya de Hernandez, someone from Bogota,
Columbia, suspected of smuggling drugs in her alimentary canal, refused to consent to an X-ray
examination. In an attempt to verify or dispel their suspicions that she was engaged in criminal
activity, Customs officers detained Ms. Montoya de Hernandez for over 16 hours and told her she
could not leave until she eliminated the contents of her alimentary canal into a wastebasket.

73 See Montoya de Hernandez, 473 U.S. at 541 citing Terry, 392 U.S. at 21 (“And in justifying the particular intrusion
the police officer must be able to point to specific and articulable facts which, taken together with rational inferences
from those facts, reasonably warrant that intrusion.”).
74 484 F.2d 645 (5th Cir. 1973). But see Reid v. Georgia, 448 U.S. 438, 441(1980) (rejecting the argument that arrival
from a source location could, by itself, provide reasonable suspicion).
75 See Montoya de Hernandez, 473 U.S. at 541 n.4.
76 Id. at 541.
77 Id. at 540.
78 See, e.g., United States v. Charleus, 871 F.2d 265, 268 n.2 (2d Cir. 1989); United States v. Oyekan, 786 F.2d 832,
837-39 (8th Cir. 1986); Bradley v. United States, 299 F.3d 197, 202-04 (3d Cir. 2002). United States v. Aguebor, 1999
U.S. App. Lexis 25, at *9 (4th Cir. January 4, 1999) (This unpublished opinion is cited merely as an example and is not
intended to have precedential value.).
79 See, e.g., United States v. Ramos-Saenz, 36 F.3d 59, 61 (9th Cir. 1994) (requiring the higher “clear indication”
standard for a body cavity search); United States v. Ek, 676 F.2d 379, 382 (9th Cir. 1982) (requiring a “clear indication”
for X-ray search).
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The Court determined “that the detention of a traveler at the border, beyond the scope of a routine
Customs search and inspection, is justified at its inception if Customs agents, considering all the
facts surrounding the traveler and her trip, reasonably suspect that the traveler is smuggling
contraband in her alimentary canal.”80 The Court concluded that it was reasonable to detain Ms.
Montoya de Hernandez for the period of time necessary to verify or dispel the suspicion of the
agents in these circumstances. 81 Courts have reasoned that “an otherwise permissible border
detention does not run afoul of the Fourth Amendment simply because a detainee’s intestinal
fortitude leads to an unexpectedly long period of detention.”82 However, the Fifth Circuit in
United States v. Adekunle concluded that the government must, within a reasonable time
(generally within 48 hours), seek a judicial determination that reasonable suspicion exists to
detain a suspect for an extended period of time.83
There appear to be no “hard-and-fast time limits” that automatically transform what would
otherwise be a routine search into a non-routine search, nor render a non-routine search
conducted under the reasonable suspicion standard unconstitutional.84 Rather, courts consider
“whether the detention of [the traveler] was reasonably related in scope to the circumstances
which justified it initially.”85 In order to provide perspective, the 16-hour detention in Montoya de
Hernandez was considered a non-routine search (justifiable by reasonable suspicions),86 while a
one-hour vehicular search did not require reasonable suspicion.87 The Second Circuit has
characterized four- to six-hour-long detentions of individuals suspected of having terrorist ties as
routine.88
Strip Searches
A strip search involves the removal of all or part of a suspect’s clothing in order to effect a search.
Because of the perceived offensiveness of the procedure due to the embarrassment it may inflict
on the individual, reviewing courts generally require reasonable suspicion that the person is
concealing contraband under his clothing before such a search is justified.89 Often, in the course
of a routine search, reasonable suspicion may arise to justify a subsequent strip search. For

80 Montoya de Hernandez, 473 U.S. at 541. See also United States v. Esieke, 940 F.2d 29 (2d Cir. 1991) (court upheld a
detention of one and half days before first bowel movement and another two and half days until all balloons were
expelled); United States v. Yakubu, 936 F.2d 936 (7th Cir. 1991) (16-hour detention upheld after refusal to be X-rayed).
81 Montoya de Hernandez does not stand for a “detention until defecation” proposition. The court narrowly decided that
the particular detention “was not unreasonably long” under “these circumstances.” In fact, the agents expected Ms.
Montoya de Hernandez to produce a bowel movement without extended delay because she had just disembarked from a
10-hour flight. 4 Wayne R. LaFave, Search and Seizure, A Treatise on the Fourth Amendment §10.5(b), 546 (3d ed.
1996 & Supp. 2003).
82 Esieke, 940 F.2d at 35.
83 2 F.3d 559, 562 (5th Cir. 1993). The court opined that a formal determination is not necessary; rather, an informal
presentation of the evidence supporting the government’s suspicion before a neutral and detached judicial officer
satisfies this requirement. Furthermore, the court concluded that the failure to obtain such a judicial determination
within 48 hours shifts the burden to the government to demonstrate a bona fide emergency justifying the extended
detainment.
84 See Tabbaa v. Chertoff, 509 F.3d 89, 99 (2d Cir. 2007) (quoting Montoya de Hernandez, 473 U.S. at 543).
85 Tabbaa, 509 F.3d at 99.
86 Montoya de Hernandez, 473 U.S. at 535.
87 Flores-Montano, 541 U.S. at 151.
88 Tabbaa, 509 F.3d at 99.
89 United States v. Chase, 503 F.2d 571 (9th Cir. 1974).
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instance, in United States v. Flores, upon discovering 600 small undeclared emerald stones in the
defendant’s pockets during a routine search, Customs agents conducted a strip search and
discovered an envelope of narcotics.90 The court held that the prior discovery of the undeclared
emeralds was sufficient to heighten suspicion to the level necessary to conduct the strip search.91
Body Cavity Searches
Narcotics and other contraband have often been smuggled in the body cavities of travelers, and
searches into such cavities have become more commonplace. Body cavity searches may include
inspections of the vagina or rectum, or the use of emetics.92 Because of the extreme medical risks
internal drug smuggling poses to the smuggler, courts have determined that body cavity searches
and extraction of the drugs do not require the advance procurement of a search warrant from a
magistrate.93 Nevertheless, a border official must have reasonable suspicion that an individual is
attempting to smuggle contraband inside his body for a court to uphold a warrantless body cavity
search.94
Additionally, the manner in which the body cavity search is conducted must also be reasonable in
light of the circumstances. Generally, conduct that “shocks the conscience” is inherently
unreasonable.95 Such conduct has included use of a stomach pump96 and could potentially include
medical procedures performed by nonmedical personnel.97
X-Ray Searches
X-ray searches of the body have also been used at the border. They raise Fourth Amendment
concerns because individuals normally have a heightened expectation of privacy with respect to

90 477 F.2d 608 (1st Cir. 1973).
91 Id.
92 See, e.g., United States v. Ogberaha, 771 F.2d 655, 657 (2d Cir. 1985) (vagina); United States v. Pino, 729 F.2d 1357,
1358 (11th Cir. 1984) (rectum); United States v. Briones, 423 F.2d 742, 743 (5th Cir. 1970) (emetics).
93 See, e.g., United States v. Sosa, 469 F.2d 271 (9th Cir. 1972) (no warrant for rectal probe); United States v. Mason,
480 F.2d 563 (9th Cir. 1973) (no warrant for vaginal probe); United States v. Briones, 423 F.2d 742 (5th Cir. 1970) (no
warrant for administration of an emetic). But see United States v. Holtz, 479 F.2d 89 (9th Cir. 1973) (Ely, J.,
dissenting); Blefare v. United States, 362 F.2d 870 (9th Cir. 1966) (Ely, J., dissenting).
94 See, e.g., United States v. Ogberaha, 771 F.2d 658 (2d Cir. 1985); Swain v. Spinney, 117 F.3d 1, 7 (1st Cir. 1997)
(only required reasonable suspicion for visual body cavity search); United States v. Gonzalez-Ricon, 36 F.3d 859, 864
(9th Cir. 1984) (noting in dictum that a body cavity search must be supported by reasonable suspicion). Due to the
intrusiveness of alimentary canal searches, some courts had required a “clear indication” (a suggestion that is free from
doubt) of alimentary canal smuggling to justify the search. See, e.g., United States v. Ramos-Saenz, 36 F.3d 59, 61 (9th
Cir. 1994) (affirming clear indication standard). But since the Supreme Court expressed its disapproval of suspicion
standards other than “reasonable suspicion” in Montoya de Hernandez, courts have been unwilling to adopt the “clear
indication” standard for body cavity searches. See, e.g., United States v. Ogberaha, 771 F.2d 658 (2d Cir. 1985); Swain
v. Spinney, 117 F.3d 1, 7 (1st Cir. 1997) (only required reasonable suspicion for visual body cavity search); United
States v. Bravo, 295 F.3d 1002 (9th Cir. 2002) (noting in dictum that a body cavity search must be supported by
reasonable suspicion).
95 Rochin v. California, 342 U.S. 165 (1952).
96 Id.
97 Rectal searches have been upheld when conducted by medical personnel using accepted and customary medical
techniques in medical surroundings. See, e.g., Rivas v. United States, 368 F.2d 703 (9th Cir. 1966) (upholding rectal
search by a doctor at doctor’s office).
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their person.98 Because these searches do not constitute an actual physical invasion, however, the
question becomes to what degree do X-ray searches intrude on this privacy?
The answer seems to turn, in large part, on whether an involuntary X-ray search is more akin to a
strip search and thus only requires a “reasonable suspicion” for its application, or whether the
intrusion is so great that it could potentially require a greater level of suspicion. In examining this
issue, the Eleventh Circuit in United States v. Vega-Barvo determined that an X-ray search
imposes only minimally on a person’s dignity, less so than a strip search.99 In reaching this
conclusion, the Vega-Barvo court examined (1) the physical contact between the searcher and the
person searched, (2) the exposure of intimate body parts, and (3) the use of force.100 These factors
helped the court examine the level of intrusiveness endured by the defendant and to conclude that
the government agents, acting under a reasonable suspicion of illegal activity, properly detained
and X-rayed the smuggler. The court reasoned that X-rays do not require physical contact or
usually expose intimate body parts. The court also determined that “an x-ray is one of the more
dignified ways of searching the intestinal cavity.”101 In general, other courts appear to agree with
the Eleventh Circuit, likening X-ray searches to strip searches, and thus concluding that
“reasonable suspicion” is the level of suspicion necessary to conduct an X-ray examination.102
Cumulative Effect of Multiple Routine Searches
Some have argued that subjecting an individual at the border to multiple routine searches during a
period of detention can rise to the level of a non-routine search. This argument was raised in
Tabbaa v. Chertoff, where the plaintiffs alleged that they were subjected to intrusive questioning,
pat-down searches, the forcible spreading of their feet, and being fingerprinted and photographed,
all in the course of a four- to six-hour period of detention at the border.103 The Second Circuit first
noted that, based on prior case law, “each of the individual elements of the searches was
routine.”104 However, even though the court did “leave open the possibility that in some
circumstances the cumulative effect of several routine search methods could render an overall
search non-routine,” the court did not find this particular sequence of search methods to be non-
routine.105 The decisive factor in determining whether a search is non-routine, said the court, is
“the invasiveness of privacy” the search caused to the traveler, rather than the level of
inconvenience. In this particular case, even taken collectively, the court found that the searches
“were routine in the border context, albeit near the outer limits of what is permissible absent

98 United States v. Vega-Barvo, 729 F.2d 1341, 1345-46 (11th Cir. 1984).
99 Id.
100 Id. at 1346.
101 Id. at 1348.
102 See supra “Non-Routine Searches.” Although some courts had previously required the more stringent “clear
indication” standard for X-ray searches, ever since the Supreme Court denounced “clear indication” in Montoya de
Hernandez, courts now generally analogize X-rays with strip searches and only require reasonable suspicion. Compare
United States v. Ek, 676 F.2d 379, 382 (9th Cir. 1982) (determining that while an X-ray search may not be as
humiliating as a strip search, “it is more intrusive since the search is potentially harmful to the health of the suspect”)
with United States v. Oyekan, 786 F.2d 832, 837 (8th Cir. 1986) (requiring reasonable suspicion for X-ray search);
United States v. Pino, 729 F.2d 1357, 1359 (11th Cir. 1984) (X-ray search equal to strip search).
103 509 F.3d 89, 99 (2d Cir. 2007).
104 Id.
105 Id.
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reasonable suspicion.”106 Thus, while in this particular circumstance, the series of searches was
found to be routine, the Second Circuit left open the possibility that “the cumulative effect of
several routine searches” could rise to the level of a non-routine search.107
Searches and Seizures of Vehicles
Although federal courts had initially analyzed vehicular border searches by evaluating whether
they were routine or non-routine, a 2004 decision by the Supreme Court appears to have placed
this practice into question. In United States v. Flores-Montano, the Supreme Court found that the
dignity and privacy interests that require reasonable suspicion for highly intrusive searches of the
person do not apply to vehicles being examined at the border.108
Prior to Flores-Montano, federal courts had concluded that border searches of personal property
involving the use of “force” could be considered “non-routine,” thus requiring reasonable
suspicion in order to be justified under the Fourth Amendment.109 In this vein, courts found that
drilling a hole into personal property, such as a container or a vehicle, to explore its interior made
the searches non-routine.110
However, the Supreme Court in Flores-Montano held that a border search involving the
dismantling, removal, and reassembly of a vehicle’s fuel tank did not require reasonable
suspicion. The Court, in its reasoning, relied on what it characterized as the United States’
longstanding right as a sovereign “to protect itself by stopping and examining persons and
property crossing into [the] country….”111 In light of the government’s need to stem the flow of
drugs smuggled across the United States’ border, the Court determined that the “inherent
authority to protect, and a paramount interest in protecting, its territorial integrity” amply justified
the search of the vehicle.112
Furthermore, in upholding the suspicionless search, the Court noted that the search at issue
resulted in the vehicle ultimately being reassembled, which differs significantly from a potentially
destructive search that involves drilling.113 The Court concluded that “while it may be true that
some searches of property are so destructive as to require a different result, this was not one of
them.”114 The Court, however, left open the question of “whether, and under what circumstances,

106 Id.
107 Id.
108 United States v. Flores-Montano, 541 U.S. 149, 152 (2004) (“Complex balancing tests to determine what is a
‘routine’ search of a vehicle, as opposed to a more ‘intrusive’ search of a person, have no place in border searches of
vehicles.”).
109 See, e.g., United States v. Robles, 45 F.3d 1, 5 (1st Cir. 1995).
110 Id. (drilling a hole into a metal cylinder transported to an airport on an international flight was a non-routine search);
United States v. Rivas, 157 F.3d 364, 367 (5th Cir. 1998) (drilling a hole into a tractor-trailer’s frame was a non-routine
search); United States v. Carreon, 872 F.2d 1436, 1440-41 (10th Cir. 1989) (implicitly requiring that drilling a hole into
a camper wall in order to effect a search of its interior required reasonable suspicion to be justified).
111 Id. at 152-53 quoting Ramsey, 431 U.S. at 616.
112 Id. at 153.
113 Id. at 155, n.2 (citing Rivas, 157 F.3d 364 (5th Cir. 1998) (drilling into body of trailer required reasonable suspicion);
United States v. Robles, 45 F.3d 1 (1st Cir. 1995) (drilling into machine part required reasonable suspicion); United
States v. Carreon, 872 F.2d 1436 (10th Cir. 1989) (drilling into camper required reasonable suspicion).
114 Flores-Montano, 541 U.S. at 155-156.
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a border search might be deemed ‘unreasonable’ because of the particularly offensive manner [in
which] it is carried out.”115 Thus, reasonable suspicion may not be presumptively required to
justify invasive vehicle searches because they do not implicate the same privacy interest as
invasive searches of the human body; however, especially destructive searches of vehicles, and
perhaps other forms of personal property, may require reasonable suspicion.116
Subsequently, federal courts have determined that the use of the routine/non-routine analysis for
vehicular border searches has been “specifically refuted” by Flores-Montano.117 These courts
now rely on the reasoning of Flores-Montano to permit an array of search techniques on vehicles
without requiring reasonable suspicion.118 In United States v. Cortez-Rocha, for example, the
Ninth Circuit held that reasonable suspicion was not required to justify the slashing of a vehicle’s
spare tire in order to search its interior.119 The court examined (1) the degree of damage inflicted
on the vehicle and (2) any potential effect on the safety or security of the vehicle or its
passengers. It then concluded that the “disabling of a spare tire does not undermine the immediate
safety of the vehicle or threaten the security of the vehicle’s driver or passengers.”120 Other Ninth
Circuit border search cases have upheld the drilling of a single 5/16-inch hole in the bed of a
pickup truck,121 the use of a radioactive density meter called a “Buster” to search the inside of a
spare tire,122 and the removal of an interior door panel.123 In all of these cases, the court concluded
that because safety was not compromised by the limited amount of damage inflicted on the
vehicles, reasonable suspicion was not required. Concurring opinions, however, questioned
whether the government needed a broad “suspicionless” search argument to prevail in these cases
when the results could have been sustained on the grounds that there was reasonable suspicion to
support the searches.124
Searches of Electronic Storage Devices
A developing issue is whether, at the border, the Fourth Amendment permits warrantless searches
of the contents of laptop computers and other electronic storage devices, and if it does, whether

115 Id. at 155, n.2.
116 Flores-Montano, 541 U.S. at 155-156; United States v. Bennett, 363 F.3d 947, 951 (9th Cir. 2004). Cf. Okafor, 285
F.3d at 846 (qualifying its holding by stating that a suspicionless X-ray search of luggage may be done at the border
“[s]o long as the means of examination are not personally intrusive, do not significantly harm the objects scrutinized,
and do not unduly delay transit”).
117 United States v. Cortez-Rocha, 394 F.3d 1115, 1119 (9th Cir. 2005).
118 Flores-Montano, 424 F.3d at 1049, n.6 (This case dealt with the same defendant as the Supreme Court case but
posed a different legal question.). See also Cortez-Rocha, 394 F.3d at 1119; United States v. Chaudhry, 424 F.3d 1051,
1054 (9th Cir. 2005).
119 Cortez-Rocha, 394 F.3d 1115.
120 Id. at 1119-1120.
121 United States v. Chaudhry, 424 F.3d 1051, 1053 (9th Cir. 2005).
122 United States v. Camacho, 368 F.3d 1182 (9th Cir. 2004). The Ninth Circuit in this case distinguished prior
precedent (Ek, 676 F.2d 379) requiring a heightened level of suspicion for X-ray searches of persons because such
searches were potentially harmful to the health of the suspect, whereas the “Buster” search was not harmful to
motorists.
123 United States v. Hernandez, 424 F.3d 1056 (9th Cir. 2005).
124 Chaudhry, 424 F.3d at 1054-1055 (Fletcher, J., concurring) (“In each case, the government chose to create a dispute
where none existed, rather than to prove up its officers’ valid suspicions.”); (Fisher, J. concurring) (“I am troubled by
the government’s evident decision in this and other cases to eschew reliance on dog alerts or other evidence supporting
reasonable suspicion.”) Id. at 1055.
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these searches are routine or non-routine.125 The U.S. Supreme Court has yet to address this
matter. Some lower federal courts, however, have held that searches of laptops and other forms of
electronic storage devices fall under the border search exception.126 Yet, these courts have also
been far more reticent in determining whether these types of searches are routine or non-routine.
Instead, they have found that reasonable suspicion supported the searches, and, thus, they did not
reach the question.127 Even when a court has held that searches of electronic storage devices were
routine, there has usually been an accompanying finding of reasonable suspicion to support the
searches.128 The one exception is the Ninth Circuit, which has expressly held that reasonable
suspicion is not required to support a border search of an electronic storage device.129
In United States v. Arnold, the Ninth Circuit, while disregarding the traditional routine/non-
routine analysis following the Supreme Court’s apparent rejection of such an analysis with
respect to border searches of property, expressly held that reasonable suspicion was not required
to support a border search of an electronic storage device.130 Rather than evaluate the
circumstances of the search and consider the particular characteristics of electronic storage
devices, the court described the search as that of a “closed container.”131 Applying a “closed
container” analysis, the court concluded that there was no material difference between a search of
an electronic storage device and the search of a briefcase, purse, pocket, or pictures and film, and
thus, like any border search of any “closed container,” reasonable suspicion was not required.132
According to the Ninth Circuit, the only two types of border searches of closed containers that
would require reasonable suspicion are searches that involve “exceptional damage of property” or
searches conducted in a “particularly offensive manner.”133 The court, in its holding, expressly
concluded that nothing about an electronic storage device, such as its large storage capacity or its
ability to contain personal information, renders a search of its contents inherently offensive.134
Thus, the court held, border search at issue in Arnold did not require reasonable suspicion.135

125 See CRS Report RL34404, Border Searches of Laptop Computers and Other Electronic Storage Devices, by Yule
Kim, Border Searches of Laptop Computers and Other Electronic Storage Devices, by Yule Kim for an in-depth
analysis of this issue.
126 See, e.g., United States v. Ickes, 393 F.3d 501, 505 (4th Cir. 2005); United States v. Romm, 455 F.3d 990, 997 (9th
Cir. 2006); United States v. Irving, 452 F.3d 110, 123 (2d Cir. 2006); United States v. Furukawa, No. 06-145, slip op.
(D. Minn., November 16, 2006), 2006 U.S. Dist. LEXIS 83767; United States v. Hampe, No. 07-3-B-W, slip op. (D.
Me., April 18, 2007), 2007 U.S. Dist. LEXIS 29218.
127 See, e.g., Irving, 452 F.3d at 124 (“Because these searches were supported by reasonable suspicion, we need not
determine whether they were routine or non-routine.”); Furukawa, supra (“[T]he court need not determine whether a
border search of a laptop is ‘routine’ for purposes of the Fourth Amendment because, regardless, the magistrate judge
correctly found the customs official had a reasonable suspicion in this case.”).
128 Ickes, 393 F.3d at 507 (noting that the computer search did not begin until the custom agents found marijuana
paraphernalia and child pornography which raised a reasonable suspicion); Hampe, supra (holding that even though the
laptop search did not implicate any of the serious concerns that would characterize a search as non-routine, that the
peculiar facts of the case gave rise to reasonable suspicions).
129 United States v. Arnold, 533 F.3d 1003 (9th Cir. 2008).
130 Id. at 1008.
131 Id. at 1007.
132 Id.
133 Id. at 1007-08.
134 Id. at 1009-10.
135 As a side note, even though these cases usually arise in child pornography prosecutions, there are national security
implications involved as well. For example, one of the justifications given for not requiring probable cause to conduct a
laptop search is that to do so would enable terrorists to smuggle potentially incriminating information on electronic
media without fear of it being searched. Ickes, 393 F.3d at 506. Another potential issue that might arise is the
(continued...)
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Searches of Expressive Materials
Some have argued that border searches of letters, documents, and other forms of expressive
content should require some form of individualized suspicion. This argument was raised before
the Fourth Circuit in Ickes, where the defendant claimed that the suspicionless border search of
his laptop was invalid because the First Amendment protects expressive content from at-will
government perusal.136 The Fourth Circuit rejected this argument for three reasons: (1)
recognizing an expressive content exception to the border search doctrine would insulate terrorist
and criminal communications from search, (2) applying such an exception in the field would be
impractical for border officers who would have to determine, “on their feet,” whether the
expressive content they wish to search is protected by the First Amendment, and (3) a First
Amendment exception for border searches would create inconsistencies with Supreme Court
precedent which states that a higher standard than probable cause is not needed for ordinary
searches of expressive content.137 This reasoning was later endorsed by the Ninth Circuit in
Arnold, which expressly adopted the Fourth Circuit reasoning.138
Thereafter, the Ninth Circuit, en banc, reaffirmed this holding in United States v. Seljan, which
upheld the suspicionless border search of a letter which solicited sex from a child residing in the
Philippines. 139 This search was found constitutionally sound even though the scope of the statute
authorizing the search of the package containing the letter was limited to the interdiction of
undeclared currency transported across the United States’ border.140 Indeed, the Seljan majority
specifically cited Ramsey, arguably the seminal case concerning the border search doctrine, in
holding that “[a]n envelope containing personal correspondence is not uniquely protected from
search at the border.”141 Moreover, the court found additional justification for the search by
concluding that it was not unreasonable under the circumstances because the customs official did
not “read” the contents of the letter. Rather, he merely “scanned” it with his eyes, which then
gave rise to the reasonable suspicion of unlawful conduct that justified a more exacting
examination of the letter’s contents.142
Although most federal circuits addressing this issue have held that expressive materials are not
exempt from the border search exception, forceful countervailing arguments have been made. For
example, in his dissent in Seljan, Judge Alex Kozinski argued that the Fourth Amendment
provides heightened protections for expressive materials at the border.143 He made two arguments
to support this proposition. The first is based on the Fourth Amendment’s text, which contains a
specific prohibition against the unreasonable search and seizure of “papers.” Judge Kozinski

(...continued)
possibility that the search power could be abused if an officer does not need to provide an articulable reason for his
search.
136 Id. at 507-08.
137 Id. at 506-07 citing New York v. P.J. Video, 475 U.S. 868, 874 (1986). See also United States v. 37 Photographs,
402 U.S. 363, 376 (1974) (finding that particularized suspicion not required for searches of pictures, films and other
graphic materials); United States v. 12,200 Feet Reels of Super 8mm Film, 413 U.S. 128, 124-25 (1973).
138 Arnold, 533 F.3d at 1010.
139 547 F.3d 993, 996 (9th Cir. 2008).
140 Id. at 996 (citing 31 U.S.C. § 5317(b)).
141 Id. at 1003.
142 Id. at 1004.
143 Id. at 1014 (Kozinski, J., dissenting).
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argued that this specific prohibition signals the Framers’ desire to insulate expressive content, and
the personal thoughts contained therein, from unnecessary government search.144 In support of
this interpretation, Judge Kozinski provided an analysis where he cited Entick v. Carrington, an
important English common law case familiar to the Framers, which rejected “the government’s
claim of unrestrained power to search personal papers” and held that the searches and seizures of
documents violated English common law.145 According to his analysis, the prevailing view at the
time of Entick was that a search of private papers was every bit as intrusive as a body search,
which, if accurate, would indicate that the Framers intended individualized suspicion to support a
search of papers even at the border.146 Second, Judge Kozinski also distinguished Seljan from past
Supreme Court precedent by characterizing the border search exception as a means to facilitate
the interdiction of smuggled contraband.147 Thus, according to Judge Kozinski, the border search
exception should be limited to the search of “containers,” primarily for the purpose of uncovering
contraband, and should not be applied to facilitate the search of expressive materials.148
Legislative Action on Border Security
There are several bills before the 111th Congress that deal with border security. These bills follow
several that were enacted in earlier Congresses and which significantly affected border security
policy as recommended by the 9/11 Commission. The 9/11 Commission made several
recommendations and observations in its Report for changes to U.S. border security operations.
Most of these proposed changes involve enhancing the detection of travelers who would pose the
United States harm and promoting cooperation between U.S. federal agencies and with foreign
governments. The 9/11 Report emphasizes the importance of constraining and intercepting
terrorist travel by using better technology and training to detect falsified documents.149 To
accomplish this end, the Commission recommended: (1) creating a strategy to combine terrorist
intelligence, operations and law enforcement; (2) integrating the U.S. border security system into
a larger network of screening points; (3) implementing a biometric entry-exit screening system;
and (4) enhancing international cooperation, particularly with Canada and Mexico, to raise global
border security standards.150 Some of these recommendations, and others, were implemented by
the 108th Congress in the 9/11 Intelligence Reform and Terrorism Prevention Act of 2004 (P.L.
108-458)—a compromise piece of legislation drawn from H.R. 10, the 9/11 Recommendations
Implementation Act and S. 2845, the National Intelligence Reform Act of 2004 during
conference.
Subsequently, the 109th Congress passed the 9/11 Intelligence Reform law and the FY2005
Emergency Supplemental Appropriation Act for Defense, the Global War on Terror, and Tsunami
Relief (P.L. 109-13), which calls on DHS to study the technology, equipment, and personnel
needed to address security vulnerabilities near the U.S. borders and to develop a pilot program to

144 Id. at 1017-19 (Kozinski, J., dissenting).
145 Id. at 1017 (Kozinksi, J., dissenting) (citing Entick v. Harrington, 19 Howell’s State Trials 1029, 95 Eng. Rep. 807
(1765)).
146 Id. (Kozinski, J., dissenting).
147 Id. at 1016. (Kozinski, J., dissenting).
148 Id. at 1014-15 (Kozinski, J., dissenting).
149 The 9/11 Commission Report: Final Report on the National Commission on Terrorist Attacks Upon the United
States, p. 385 (Official Gov’t Ed. 2004).
150 Id. at 385-390.
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utilize or increase the use of ground surveillance technologies (e.g., video cameras, sensor
technology, motion detectors) on both the northern and southern borders. The 109th Congress also
passed the Secure Fence Act of 2006 (P.L. 109-367), which requires the Secretary of DHS to take
all actions the Secretary determines necessary to achieve and maintain operational control over
the entire international land and maritime borders of the United States. The Secretary is to use
systematic surveillance and physical infrastructure enhancements, including fencing, to achieve
control of the border.
The 110th Congress continued to address border security issues covered by the 9/11 Commission
in the Implementing Recommendations of the 9/11 Commission Act of 2007.151 This law attempts
to modernize and strengthen the visa waiver program in INA § 217 by enhancing program
security requirements through an electronic travel authorization system to collect biographical
information about passengers, and extending visa-free travel privileges to nationals of countries
that are cooperating with the United States in its anti-terrorism campaign. The law also
authorizes: (1) a Terrorist Travel Program to monitor terrorists and prevent their entry into the
United States, (2) the creation of a “model” port-of-entry program to help provide a more
efficient and welcoming international arrival process at ports-of-entry, and (3) a pilot program to
develop, with states, a machine-readable and tamper-proof driver’s license that can be used for
admission into the United States from either the Canadian or Mexican border.
In the current Congress, several additional proposals relate to border security and may have the
potential to implicate Fourth Amendment concerns. These include the following:
• H.R. 1900 was introduced to provide emergency deployments of CBP, DEA, and
ATF agents to the border and to authorize funds to local law enforcement to stem
the illegal trafficking of firearms into Mexico. S. 205, H.R. 495, and H.R. 1448
would also authorize funds for ATF agents to interdict the illegal trafficking of
firearms to Mexico.
• H.R. 239, the Securing our Borders and our Data Act of 2009, would prohibit
searches of digital media devices based solely on the border search authority.
Rather, border agents could only conduct searches of digital devices if they have
reasonable suspicions of unlawful conduct. Border agents also would be
prohibited from seizing digital devices based solely on their border search
authority; some other undescribed constitutional authority would be required.
• H.R. 1726, the Border Security Search Accountability Act of 2009, would
mandate that the Commissioner of Customs and Border Protection promulgate a
rule with respect to the scope of and procedural and recordkeeping requirements
associated with border security searches of electronic devices. The rule would
require that (1) commercial information be handled in a manner consistent with
all laws and regulations governing such information, (2) electronic searches be
conducted in front of a supervisor, (3) the number of days commercial
information could be retained without probable cause be determined, (4) the
individual whose information was seized be notified if the information is entered
into an electronic database, (5) an individual receive a receipt if his device is
seized during a border search, (6) an individual subject to a border search of an
electronic device receive notice as to how he can report any abuses or concerns

151 Implementing Recommendations of 9/11 Commission Act of 2007, P.L. 110-53, 121 Stat. 266.
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related to the search, (7) the rights of individuals with regard to border searches
be posted at all ports of entry, (8) that a privacy impact assessment of the rule be
made, and (9) a civil rights impact assessment of the rule be made.

Author Contact Information

Yule Kim

Legislative Attorney
ykim@crs.loc.gov, 7-9138


Acknowledgments
This report was originally prepared by Stephen R. Viña. Yule Kim has rewritten and updated the report and
is available to answer questions about these issues.



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