In the

    United States Court of Appeals
                For the Seventh Circuit
                    ____________________
No. 23-1460
UNITED STATES OF AMERICA,
                                                  Plaintiff-Appellee,
                                v.

MARCOS MENDEZ,
                                              Defendant-Appellant.
                    ____________________

        Appeal from the United States District Court for the
          Northern District of Illinois, Eastern Division.
           No. 16-cr-163 — Mary M. Rowland, Judge.
                    ____________________

    ARGUED DECEMBER 5, 2023 — DECIDED JUNE 10, 2024
               ____________________

   Before HAMILTON, BRENNAN, and ST. EVE, Circuit Judges.
    ST. EVE, Circuit Judge. Marcos Mendez was passing
through customs at O’Hare International Airport after a trip
abroad when a customs agent pulled him aside for inspection,
unlocked and scrolled through his cell phone, and found child
pornography in the photo gallery. Customs agents then
seized the phone, downloaded its contents, and discovered
additional illicit images and videos of children.
2                                                     No. 23-1460

    After the district court denied Mendez’s motion to sup-
press this evidence, Mendez pled guilty to producing child
pornography but preserved this appeal of the district court’s
suppression-motion ruling. He now argues that the searches
of his phone, in light of the Supreme Court’s decisions in Riley
v. California, 

 (2014), and Carpenter v. United States,

 (2018), required a warrant, probable cause, or at
least reasonable suspicion.
    The “longstanding recognition that searches at our bor-
ders without probable cause and without a warrant are none-
theless ‘reasonable’ has a history as old as the Fourth Amend-
ment itself.” United States v. Ramsey, 

 (1977).
That history leads us to join the uniform view of our sister
circuits to hold that searches of electronics at the border—like
any other border search—do not require a warrant or proba-
ble cause, and that the kind of routine, manual search of the
phone initially performed here requires no individualized
suspicion. We affirm.
                         I. Background
A. Factual Background
   Just shy of midnight on February 20, 2016, Marcos Mendez
landed at O’Hare International Airport following a trip to Ec-
uador. He was traveling alone. Along with his baggage, Men-
dez carried with him three electronic devices: a personal cell
phone, a work phone, and a work iPad.
    Customs and Border Protection (“CBP”) had issued a
child-pornography-related “lookout” for Mendez based on
his arrest record and prior travel history. Mendez had a 2010
arrest relating to indecent solicitation of a child and child por-
nography, leading to a 2011 conviction for endangering the
No. 23-1460                                                   3

life or health of a child. Additionally, CBP previously had in-
spected Mendez in 2014 after he returned from Mexico. Dur-
ing that inspection, he claimed to have been kidnapped,
robbed of his electronic devices, and told to leave the country.
And on this particular trip, Mendez was returning from Ecua-
dor, which CBP officers classified as a potential child-traffick-
ing source country. Mendez also fit the profile for child-por-
nography offenders: a single adult male traveling alone.
    Together, this information prompted CBP Investigating
Officer Richard Callison to pull Mendez aside for secondary
inspection after his arrival at O’Hare. Within the first thirty
minutes of the inspection, Mendez gave Callison his cell
phone and its passcode. Callison manually unlocked the
phone and navigated to its camera roll. There he found thou-
sands of pornographic images, including what appeared to be
child pornography. Using the phone’s passcode, Callison also
opened a protected application called “iSafe,” where he dis-
covered more illicit images.
    Callison then moved Mendez to a private location, where
he conducted a more extensive, “forensic” examination of
Mendez’s devices. CBP agents used a data extraction technol-
ogy called “DOMEX” (Document and Media Exploitation) to
download a copy of the devices’ photos and videos. The fo-
rensic examination took about two hours and revealed more
child pornography.
    Officers seized Mendez’s cell phone but released Mendez,
who, in the days after his arrest, remotely wiped the contents
of his phone and traveled by car into Mexico with his mother.
Meanwhile, a Homeland Security Investigations (“HSI”) team
extracted the metadata—creation dates, geolocation infor-
mation, and so on—from the files that had earlier been
4                                                 No. 23-1460

downloaded from Mendez’s cell phone. That data revealed
that several of the child pornography images were taken near
Mendez’s residence in Rosemont, Illinois.
B. Procedural Background
    A grand jury indicted Mendez on two counts of producing
child pornography, in violation of 

(a), one
count of transporting child pornography, in violation of 18
U.S.C. § 2252A(a)(1), and one count of possessing child por-
nography, in violation of 18 U.S.C. § 2252A(a)(5)(B). He was
extradited to the United States in January 2020.
    Mendez moved to suppress the evidence found on his cell
phone, arguing the searches violated the Fourth Amendment
because they were unsupported by either a probable-cause
supported warrant or reasonable suspicion. After an eviden-
tiary hearing in which Officer Callison and other investigating
officers testified, the district court denied the motion. Relying
in large part on our decision in United States v. Wanjiku, 

 (7th Cir. 2019), the district court held that the
searches did not violate the Fourth Amendment because cus-
toms agents had reasonable suspicion by the time they began
looking through Mendez’s phone.
   Mendez pled guilty to one count of producing child por-
nography but preserved his right to appeal the district court’s
suppression ruling. He received a 300-month sentence, fol-
lowed by a ten-year term of supervised release. We now con-
sider that preserved issue, reviewing the district court’s find-
ings of fact for clear error and questions of law de novo. See
United States v. Ostrum, 

 (7th Cir. 2024).
No. 23-1460                                                                 5

                               II. Analysis
   The Fourth Amendment commands that searches and sei-
zures be reasonable. U.S. Const. amend. IV. Ordinarily, “[i]n
the absence of a warrant, a search is reasonable only if it falls
within a specific exception to the warrant requirement.” Riley,
573 U.S. at 382.
   One such exception is the border search exception. “Con-
gress, since the beginning of our Government, ‘has granted
the Executive plenary authority to conduct routine searches
and seizures at the border, without probable cause or a war-
rant, in order to regulate the collection of duties and to pre-
vent the introduction of contraband into this country.’” 1
United States v. Flores-Montano, 

 (2004) (quot-
ing United States v. Montoya de Hernandez, 

(1985)). The government’s unquestionable authority to search
persons and effects at the border is rooted in “the long-stand-
ing right of the sovereign to protect itself by stopping and ex-
amining persons and property crossing into this country.”
Ramsey, 

; see also 

 (“Historically such
broad powers have been necessary to prevent smuggling and
to prevent prohibited articles from entry.”); Flores–Montano,

 (noting that the border exception rests on the
government interest in “preventing the entry of unwanted
persons and effects”). The “Fourth Amendment balance be-
tween the interests of the Government and the privacy right


    1 We treat the customs area of O’Hare International Airport as “the

functional equivalent of an international border for the purpose of inspect-
ing persons and articles arriving on international flights.” Wanjiku, 

 (citing United States v. Yang, 

 (7th Cir. 2002));
see also Almeida-Sanchez v. United States, 

 (1973).
6                                                       No. 23-1460

of the individual is … struck much more favorably to the Gov-
ernment at the border.” Montoya de Hernandez, 

.
When the government acts under its “inherent authority to
protect … its territorial integrity,” its interest is “at its zenith.”
Flores-Montano, 541 U.S. at 152–53. In contrast, a traveler’s ex-
pectation of privacy at the border is simply “less.” Montoya de
Hernandez, 

.
    Accordingly, border searches have long been exempted
from warrant and probable cause requirements, and ordinar-
ily “are reasonable simply by virtue of the fact that they occur
at the border.” Flores-Montano, 541 U.S. at 152–53 (quoting
Ramsey, 

). “Routine” searches of people and ef-
fects at the border—which have included examining the con-
tents of a person’s purse, wallet, or pockets, United States v.
Carter, 

 (7th Cir. 1979), opening mail, see Ramsey,

, and disassembling and reassembling a vehi-
cle’s fuel tank, see Flores-Montano, 541 U.S. at 155—are “per se
reasonable” and require no particularized suspicion at all.
Yang, 

 (citing Ramsey, 

); see also
Montoya de Hernandez, 

 (“Routine searches of
the persons and effects of entrants are not subject to any re-
quirement of reasonable suspicion, probable cause, or war-
rant.”); United States v. Johnson, 

 (7th Cir.
1993).
    Even highly intrusive, so-called “non-routine” border
searches need only reasonable suspicion. See Montoya de Her-
nandez, 

. But the Supreme Court has recognized
this “non-routine” category only in searches of a suspect’s
person. It held, for example, that a 16-hour detention for mon-
itored bowel movement of a person suspected of “smuggling
contraband in her alimentary canal” requires reasonable
No. 23-1460                                                   7

suspicion given the personal dignity and privacy interests at
stake. 

. And in this circuit, “we have confronted bor-
der searches and seizures that we characterized as arguably
non-routine”—including pat downs, partial strip searches,
visual body cavity searches, and the dismantling of luggage—
and have applied the reasonable suspicion standard. Wanjiku,
919 F.3d at 482–83 (emphasis added); see also Yang, 

; Kaniff v. United States, 

, 784–85 (7th Cir.
2003); Johnson, 991 F.2d at 1291–94.
    Routine or otherwise, searches at the border “never” re-
quire a warrant or probable cause. Ramsey, 

(“There has never been any additional requirement that the
reasonableness of a border search depended on the existence
of probable cause.”). At most, border searches require reason-
able suspicion. See Wanjiku, 

; United States v.
Molina-Isidoro, 

 (5th Cir. 2018) (“For border
searches both routine and not, no case has required a war-
rant.”). In more than 200 years of border search precedent,
neither the Supreme Court nor we have ever found a border
search unconstitutional.
    Mendez argues that Riley and Carpenter upended that
precedent by recognizing that cell phones fundamentally dif-
fer from other types of personal effects. See Riley, 573 U.S. at
393; Carpenter, 

. Yet our caselaw highlights why
neither case supports altering the long-settled rule exempting
border searches from warrant and probable cause require-
ments: Riley and Carpenter had nothing to do with the border
context. See Wanjiku, 

; United States v. Wood, 

 (7th Cir. 2021) (“Given the context-specific
8                                                              No. 23-1460

nature of the Fourth Amendment, Riley is not readily transfer-
able to scenarios other than the one it addressed.”). 2
     Rather, Riley involved the search incident to arrest excep-
tion and “carefully tailored its analysis to that context.” Wood,

. What is unreasonable after arrest may be per-
fectly reasonable at customs, as Riley itself anticipated. See Ri-
ley, 573 U.S. at 401–02 (“[O]ther case-specific exceptions may
still justify a warrantless search of a particular phone.”); see
also New Jersey v. T.L.O., 

 (1985) (Fourth
Amendment reasonableness “depends on the context within
which a search takes place.”). A border search is


    2 Wanjiku and a later decision, United States v. Skaggs, 

 (7th

Cir. 2022), resolved the identical issue of electronic device searches at cus-
toms under the Fourth Amendment’s good faith exception to the warrant
requirement. “[N]o court,” we observed in Wanjiku, “had ever required
more than reasonable suspicion for any search at the border.” 

. And because we found that law enforcement had reasonable suspi-
cion to search the defendant’s phone, “[g]iven the state of the law at the
time of the[] searches,” we concluded that law enforcement had “an ob-
jectively good faith belief that their conduct did not violate the Fourth
Amendment.” 

 at 485–86. While we left the merits of the Fourth Amend-
ment issues open in those cases, we go on to reach those merits issues here
to provide clarity to law enforcement and the public on the burgeoning
practice of electronic device searches. See Molina-Isidoro, 

(Costa, J., specially concurring) (“Courts should resist the temptation to
frequently rest their Fourth Amendment decisions on the safe haven of the
good-faith exception, lest the courts fail to give law enforcement and the
public the guidance needed to regulate their frequent interactions.”);
United States v. Bosyk, 

, 332 n.10 (4th Cir. 2019) (“[W]hen a
Fourth Amendment case presents a novel question of law whose resolu-
tion is necessary to guide future action by law enforcement officers and
magistrates, there is sufficient reason for [a court] to decide the violation
issue before turning to the good-faith question.” (alterations in original)
(quoting Illinois v. Gates, 

 (1983) (White, J., concurring))).
No. 23-1460                                                                9

fundamentally different from a search incident to arrest, not
least because “the Fourth Amendment’s balance of reasona-
bleness is qualitatively different at the international border,”
where the government’s interest in protecting its territorial in-
tegrity is at its peak and travelers’ expectations of privacy are
diminished. Montoya de Hernandez, 

; cf. United
States v. 12 200-Ft. Reels of Super 8MM. Film, 

(1973) (“Import restrictions and searches of persons or pack-
ages at the national borders rest on different considerations
and different rules of constitutional law from domestic regu-
lations.”). Underlying the Court’s decision in Riley was the
fact that neither of the search incident to arrest exception’s
twin concerns—preventing harm to officers and destruction
of evidence—“ha[d] much force with respect to digital con-
tent on cell phones.” Riley, 573 U.S. at 386. Here, in contrast,
we agree with the First Circuit that “given the volume of trav-
elers passing through our nation’s borders, warrantless elec-
tronic device searches are essential to the border search ex-
ception’s purpose of ensuring that the executive branch can
adequately protect the border.” 3 Alasaad v. Mayorkas, 

, 17 (1st Cir. 2021).
   While Mendez argues that cell phone searches are unteth-
ered to the border search doctrine’s justifications, this case


    3 We have twice declined to extend Riley beyond the search incident

to arrest exception: to parolee searches in Wood, 

, and to
consent searches in United States v. Thurman, 

, 366 n.9 (7th Cir.
2018) (finding in the consent-search context that “Riley d[id] not affect our
holding” because “[a]lthough the Court discussed the unique nature of
modern cell phones as unparalleled repositories for personal information,
it did not address the consent-based exception to the warrant require-
ment”).
10                                                            No. 23-1460

illustrates that cell phones can contain the contraband the bor-
der search doctrine means to intercept: here, digital contra-
band in the form of child pornography. See United States v.
Cano, 

 (9th Cir. 2019) (“The best example
[of digital contraband] is child pornography.”). The govern-
ment’s interest in detecting child pornography at the border
is just as strong as its interest in intercepting firearms, narcot-
ics, or any other prohibited item. 4 See United States v. Touset,

 (11th Cir. 2018) (“‘[Digital]’ child pornog-
raphy poses the same exact ‘risk’ of unlawful entry at the bor-
der as its physical counterpart.”). That digital contraband like
child pornography can pass into the country electronically or
be accessed remotely does little to diminish the government’s
interest in preventing its physical entry into the country. See


     4 Although the scope of a search conducted under an exception to the

warrant requirement must be “commensurate with its purposes,” Arizona
v. Gant, 

 (2009), the Ninth Circuit is the only circuit to
cabin the border search exception to detecting contraband itself. Compare
Cano, 

 (holding that “border officials are limited to search-
ing for contraband only”), with United States v. Levy, 

 (2d
Cir. 2015) (noting that CBP officers “have the authority to search and re-
view a traveler’s documents and other items at the border when they rea-
sonably suspect that the traveler is engaged in criminal activity, even if the
crime falls outside the primary scope of their official duties.”), and United
States v. Xiang, 

 (8th Cir. 2023) (adopting the Second Cir-
cuit’s “more sensibl[e]” position), and Alasaad, 988 F.3d at 20 (“[T]he bor-
der search exception’s purpose is not limited to interdicting contraband;
it serves to bar entry to those ‘who may bring anything harmful into this
country.’” (emphasis in original) (quoting Montoya de Hernandez, 

)), and United States v. Aigbekaen, 

 (4th Cir. 2019)
(finding the purposes of the exception to be “protecting national security,
collecting duties, blocking the entry of unwanted persons, or disrupting
efforts to export or import contraband”).
No. 23-1460                                                    11

 (“If anything, the advent of sophisticated technological
means for concealing contraband only heightens the need of
the government to search property at the border.”); United
States v. Thirty-Seven Photographs, 

 (1971)
(“Customs officers characteristically inspect luggage and
their power to do so is not questioned … ; it is an old practice
and is intimately associated with excluding illegal articles
from the country.”). And although it was not the case here, a
border search of a cell phone could also facilitate the doc-
trine’s goal of “reasonably requiring one entering the country
to identify himself as entitled to come in.” Carroll v. United
States, 

 (1925).
    No circuit court has read Riley to require more than rea-
sonable suspicion to support even the most intrusive electron-
ics search at the border. See United States v. Castillo, 

, 897–98 (5th Cir. 2023) (“[W]hen it comes to manual cell
phone searches at the border, our sister circuits have uni-
formly held that Riley does not require either a warrant or rea-
sonable suspicion.”); Molina-Isidoro, 

 (5th Cir.
2018); Xiang, 

 (8th Cir. 2023) (“Riley involved a
different Fourth Amendment exception, searches incident to
arrest. No Circuit has held that the government must obtain a
warrant to conduct a routine border search of electronic de-
vices.”); Alasaad, 988 F.3d at 17 (1st Cir. 2021) (“Riley does not
command a warrant requirement for border searches of elec-
tronic devices nor does the logic behind Riley compel us to
impose one.”); Cano, 

 (9th Cir. 2019); Touset,

 (11th Cir. 2018) (“Although the Supreme
Court stressed in Riley that the search of a cell phone risks a
significant intrusion on privacy, our [caselaw makes] clear
that Riley, which involved the search-incident-to-arrest excep-
tion, does not apply to searches at the border.”); United States
12                                                   No. 23-1460

v. Vergara, 

, 1312–13 (11th Cir. 2018) (“Border
searches have long been excepted from warrant and probable
cause requirements, and the holding of Riley does not change
this rule.”); United States v. Kolsuz, 

 (4th Cir.
2018). We join our sister circuits to hold that a border search
of a cell phone or other electronic device requires neither a
warrant nor probable cause.
    The question remains whether the agent’s manual search
of Mendez’s phone—scrolling through its photo gallery—was
a routine search permissible without any suspicion or a “non-
routine” search requiring reasonable suspicion. Mendez con-
tends that because electronic devices carry potentially vast
troves of sensitive and personal information, we should treat
all electronic device searches as intrusive border searches re-
quiring at least reasonable suspicion. Riley itself involved a
manual phone search and no doubt indicates that all cell
phone searches are intrusive to some degree, but the privacy
concerns such searches implicate “are nevertheless tempered
by the fact that the searches are taking place at the border.”
Alasaad, 988 F.3d at 18. Moreover, manual electronic searches
at the border are typically “brief procedure[s]”—here, around
thirty minutes—practically limited in intrusiveness by the
fact that the customs agent cannot download and peruse the
phone’s entire contents. Instead, they must physically scroll
through the device, making it less likely for an agent to tap
into the revealing nooks and crannies of the phone’s
metadata, encrypted files, or deleted contents. Flores-Montano,

; compare United States v. Cotterman, 

 (9th Cir. 2013) (en banc) (pre-Riley decision finding
the legitimacy of a suspicion-less “quick look and unintru-
sive” manual laptop search “not in doubt”), with Kolsuz, 

 (requiring reasonable suspicion for a month-long,
No. 23-1460                                                  13

off-site forensic analysis that yielded a nearly 900-page report
cataloguing the phone’s data).
    We therefore agree with the consensus among circuits that
brief, manual searches of a traveler’s electronic device are
“routine” border searches requiring no individualized suspi-
cion. See Castillo, 70 F.4th at 897–98 (“[W]hen it comes to man-
ual cell phone searches at the border, our sister circuits have
uniformly held that Riley does not require either a warrant or
reasonable suspicion.”); Alasaad, 988 F.3d at 19 (“[B]asic bor-
der searches [of electronic devices] are routine searches and
need not be supported by reasonable suspicion.”); Cano, 

 (“[M]anual searches of cell phones at the border
are reasonable without individualized suspicion.”); Touset,

; Kolsuz, 

 n.5 (describing United
States v. Ickes, 

 (4th Cir. 2005), as “treat[ing] a
[basic] search of a computer as a routine border search, requir-
ing no individualized suspicion”).
    The only point of divergence among the circuits is whether
more intrusive, forensic electronic device searches require in-
dividualized suspicion. Compare Touset, 890 F.3d at 1231 (no
suspicion required for forensic electronics search), with Cano,

 (reasonable suspicion required). We need not
resolve this issue today because this case does not require it.
The valid manual search of Mendez’s phone revealed child
pornography. So, even if the extensive forensic searches that
followed required reasonable suspicion, customs agents had
that and more once they found illicit images and videos of
children on Mendez’s phone during the routine search.
                                                      AFFIRMED