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SUPREME COURT OF THE UNITED STATES
_________________
Nos. 13–132 and 13–212
_________________
DAVID LEON RILEY, PETITIONER
13–132 v.
CALIFORNIA
on writ of certiorari to the court of appeal
of cali-fornia, fourth appellate district, division one
UNITED STATES, PETITIONER
13–212 v.
BRIMA WURIE
on writ of certiorari to the united states
court of appeals for the first circuit
[June 25, 2014]
Chief Justice Roberts
delivered the opinion of the Court.
These two cases raise a
common question: whether the police may, without a warrant, search
digital information on a cell phone seized from an individual who
has been arrested.
I
A
In the first case,
petitioner David Riley was stopped by a police officer for driving
with expired registration tags. In the course of the stop, the
officer also learned that Riley’s license had been suspended.
The officer impounded Riley’s car, pursuant to department
policy, and another officer conducted an inventory search of the
car. Riley was arrested for possession of concealed and loaded
firearms when that search turned up two handguns under the
car’s hood. See Cal. Penal Code Ann. §§12025(a)(1),
12031(a)(1) (West 2009).
An officer searched
Riley incident to the arrest and found items associated with the
“Bloods” street gang. He also seized a cell phone from
Riley’s pants pocket. According to Riley’s
uncontradicted assertion, the phone was a “smart
phone,” a cell phone with a broad range of other functions
based on advanced computing capability, large storage capacity, and
Internet connectivity. The officer accessed information on the
phone and noticed that some words (presumably in text messages or a
contacts list) were preceded by the letters
“CK”—a label that, he believed, stood for
“Crip Killers,” a slang term for members of the Bloods
gang.
At the police station
about two hours after the arrest, a detective specializing in gangs
further examined the contents of the phone. The detective testified
that he “went through” Riley’s phone
“looking for evidence, because . . . gang members
will often video themselves with guns or take pictures of
themselves with the guns.” App. in No. 13–132, p. 20.
Although there was “a lot of stuff” on the phone,
particular files that “caught [the detective’s]
eye” included videos of young men sparring while someone
yelled encouragement using the moniker “Blood.” Id., at
11–13. The police also found photographs of Riley standing in
front of a car they suspected had been involved in a shooting a few
weeks earlier.
Riley was ultimately
charged, in connection with that earlier shooting, with firing at
an occupied vehicle, assault with a semiautomatic firearm, and
attempted murder. The State alleged that Riley had committed those
crimes for the benefit of a criminal street gang, an aggravating
factor that carries an enhanced sentence. Compare Cal. Penal Code
Ann. §246 (2008) with §186.22(b)(4)(B) (2014). Prior to
trial, Riley moved to suppress all evidence that the police had
obtained from his cell phone. He contended that the searches of his
phone violated the Fourth Amendment, because they had been
performed without a warrant and were not otherwise justified by
exigent circumstances. The trial court rejected that argument. App.
in No. 13–132, at 24, 26. At Riley’s trial, police
officers testified about the photographs and videos found on the
phone, and some of the photographs were admitted into evidence.
Riley was convicted on all three counts and received an enhanced
sentence of 15 years to life in prison.
The California Court of
Appeal affirmed. No. D059840 (Cal. App., Feb. 8, 2013), App. to
Pet. for Cert. in No. 13–132, pp. 1a–23a. The court
relied on the California Supreme Court’s decision in People
v. Diaz, 51 Cal. 4th 84, 244 P. 3d 501 (2011), which held that the
Fourth Amendment permits a warrantless search of cell phone data
incident to an arrest, so long as the cell phone was immediately
associated with the arrestee’s person. See id., at 93, 244 P.
3d, at 505–506.
The California Supreme
Court denied Riley’s petition for review, App. to Pet. for
Cert. in No. 13–132, at 24a, and we granted certiorari, 571
U. S. ___ (2014).
B
In the second case, a
police officer performing routine surveillance observed respondent
Brima Wurie make an apparent drug sale from a car. Officers
subsequently arrested Wurie and took him to the police station. At
the station, the officers seized two cell phones from Wurie’s
person. The one at issue here was a “flip phone,” a
kind of phone that is flipped open for use and that generally has a
smaller range of features than a smart phone. Five to ten minutes
after arriving at the station, the officers noticed that the phone
was repeatedly receiving calls from a source identified as
“my house” on the phone’s external screen. A few
minutes later, they opened the phone and saw a photograph of a
woman and a baby set as the phone’s wallpaper. They pressed
one button on the phone to access its call log, then another button
to determine the phone number associated with the “my
house” label. They next used an online phone directory to
trace that phone number to an apartment building.
When the officers went
to the building, they saw Wurie’s name on a mailbox and
observed through a window a woman who resembled the woman in the
photograph on Wurie’s phone. They secured the apartment while
obtaining a search warrant and, upon later executing the warrant,
found and seized 215 grams of crack cocaine, mari-juana, drug
paraphernalia, a firearm and ammunition, and cash.
Wurie was charged with
distributing crack cocaine, possessing crack cocaine with intent to
distribute, and being a felon in possession of a firearm and
ammunition. See 18 U. S. C. §922(g); 21
U. S. C. §841(a). He moved to suppress the evidence
obtained from the search of the apartment, arguing that it was the
fruit of an unconstitutional search of his cell phone. The District
Court denied the motion. 612 F. Supp. 2d 104 (Mass. 2009).
Wurie was convicted on all three counts and sentenced to 262 months
in prison.
A divided panel of the
First Circuit reversed the denial of Wurie’s motion to
suppress and vacated Wurie’s convictions for possession with
intent to distribute and possession of a firearm as a felon. 728
F. 3d 1 (2013). The court held that cell phones are distinct
from other physical possessions that may be searched incident to
arrest without a warrant, because of the amount of personal data
cell phones contain and the negligible threat they pose to law
enforcement interests. See id., at 8–11.
We granted certiorari.
571 U. S. ___ (2014).
II
The Fourth Amendment
provides:
“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,
supported by Oath or affirmation, and particularly describing the
place to be searched, and the persons or things to be
seized.”
As the text makes
clear, “the ultimate touchstone of the Fourth Amendment is
‘reasonableness.’ ” Brigham City v. Stuart,
547 U. S. 398, 403 (2006) . Our cases have determined that
“[w]here a search is undertaken by law enforcement officials
to discover evidence of criminal wrongdoing, . . .
reasonableness generally requires the obtaining of a judicial
warrant.” Vernonia School Dist. 47J v. Acton, 515 U. S.
646, 653 (1995) . Such a warrant ensures that the inferences to
support a search are “drawn by a neutral and detached
magistrate instead of being judged by the officer engaged in the
often competitive enterprise of ferreting out crime.” Johnson
v. United States, 333 U. S. 10, 14 (1948) . In the absence of
a warrant, a search is reasonable only if it falls within a
specific exception to the warrant requirement. See Kentucky v.
King, 563 U. S. ___, ___ (2011) (slip op., at 5–6).
The two cases before us
concern the reasonableness of a warrantless search incident to a
lawful arrest. In 1914, this Court first acknowledged in dictum
“the right on the part of the Government, always recognized
under English and American law, to search the person of the accused
when legally arrested to discover and seize the fruits or evidences
of crime.” Weeks v. United States, 232 U. S. 383 . Since
that time, it has been well accepted that such a search constitutes
an exception to the warrant requirement. Indeed, the label
“exception” is something of a misnomer in this context,
as warrantless searches incident to arrest occur with far greater
frequency than searches conducted pursuant to a warrant. See 3 W.
LaFave, Search and Seizure §5.2(b), p. 132, and n. 15 (5th ed.
2012).
Although the existence
of the exception for such searches has been recognized for a
century, its scope has been de-bated for nearly as long. See
Arizona v. Gant, 556 U. S. 332, 350 (2009) (noting the
exception’s “checkered his-tory”). That debate
has focused on the extent to which officers may search property
found on or near the arrestee. Three related precedents set forth
the rules governing such searches:
The first, Chimel v.
California, 395 U. S. 752 (1969) , laid the groundwork for
most of the existing search incident to arrest doctrine. Police
officers in that case arrested Chimel inside his home and proceeded
to search his entire three-bedroom house, including the attic and
garage. In particular rooms, they also looked through the contents
of drawers. Id., at 753–754.
The Court crafted the
following rule for assessing the reasonableness of a search
incident to arrest:
“When an arrest is made, it is
reasonable for the arresting officer to search the person arrested
in order to remove any weapons that the latter might seek to use in
order to resist arrest or effect his escape. Otherwise, the
officer’s safety might well be endangered, and the arrest
itself frustrated. In addition, it is entirely reasonable for the
arresting officer to search for and seize any evidence on the
arrestee’s person in order to prevent its concealment or
destruction. . . . There is ample justification,
therefore, for a search of the arrestee’s person and the area
‘within his immediate control’—construing that
phrase to mean the area from within which he might gain possession
of a weapon or destructible evidence.” Id., at
762–763.
The extensive warrantless search of
Chimel’s home did not fit within this exception, because it
was not needed to protect officer safety or to preserve evidence.
Id., at 763, 768.
Four years later, in
United States v. Robinson, 414 U. S. 218 (1973) , the Court
applied the Chimel analysis in the context of a search of the
arrestee’s person. A police officer had arrested Robinson for
driving with a revoked license. The officer conducted a patdown
search and felt an object that he could not identify in
Robinson’s coat pocket. He removed the object, which turned
out to be a crumpled cigarette package, and opened it. Inside were
14 capsules of heroin. Id., at 220, 223.
The Court of Appeals
concluded that the search was unreasonable because Robinson was
unlikely to have evidence of the crime of arrest on his person, and
because it believed that extracting the cigarette package and
opening it could not be justified as part of a protective search
for weapons. This Court reversed, rejecting the notion that
“case-by-case adjudication” was required to determine
“whether or not there was present one of the reasons
supporting the authority for a search of the person incident to a
lawful arrest.” Id., at 235. As the Court explained,
“[t]he authority to search the person incident to a lawful
custodial arrest, while based upon the need to disarm and to
discover evidence, does not depend on what a court may later decide
was the probability in a particular arrest situation that weapons
or evidence would in fact be found upon the person of the
suspect.” Ibid. Instead, a “custodial arrest of a
suspect based on probable cause is a reasonable intrusion under the
Fourth Amendment; that intrusion being lawful, a search incident to
the arrest requires no additional justification.” Ibid.
The Court thus
concluded that the search of Robinson was reasonable even though
there was no concern about the loss of evidence, and the arresting
officer had no specific concern that Robinson might be armed. Id.,
at 236. In doing so, the Court did not draw a line between a search
of Robinson’s person and a further examination of the
cigarette pack found during that search. It merely noted that,
“[h]aving in the course of a lawful search come upon the
crumpled package of cigarettes, [the officer] was entitled to
inspect it.” Ibid. A few years later, the Court clarified
that this exception was limited to “personal property
. . . immediately associated with the person of the
arrestee.” United States v. Chadwick, 433 U. S. 1, 15 (1977)
(200-pound, locked footlocker could not be searched incident to
arrest), abrogated on other grounds by California v. Acevedo, 500
U. S. 565 (1991) .
The search incident to
arrest trilogy concludes with Gant, which analyzed searches of an
arrestee’s vehicle. Gant, like Robinson, recognized that the
Chimel concerns for officer safety and evidence preservation
underlie the search incident to arrest exception. See 556
U. S., at 338. As a result, the Court concluded that Chimel
could authorize police to search a vehicle “only when the
arrestee is unsecured and within reaching distance of the passenger
compartment at the time of the search.” 556 U. S., at
343. Gant added, however, an independent exception for a
warrantless search of a vehicle’s passenger compartment
“when it is ‘reasonable to believe evidence relevant to
the crime of arrest might be found in the
vehicle.’ ” Ibid. (quoting Thornton v. United
States, 541 U. S. 615, 632 (2004) (Scalia, J., concurring in
judgment)). That exception stems not from Chimel, the Court
explained, but from “circumstances unique to the vehicle
context.” 556 U. S., at 343.
III
These cases require
us to decide how the search incident to arrest doctrine applies to
modern cell phones, which are now such a pervasive and insistent
part of daily life that the proverbial visitor from Mars might
conclude they were an important feature of human anatomy. A smart
phone of the sort taken from Riley was unheard of ten years ago; a
significant majority of American adults now own such phones. See A.
Smith, Pew Research Center, Smartphone Ownership—2013 Update
(June 5, 2013). Even less sophisticated phones like Wurie’s,
which have already faded in popularity since Wurie was arrested in
2007, have been around for less than 15 years. Both phones are
based on technology nearly inconceivable just a few decades ago,
when Chimel and Robinson were decided.
Absent more precise
guidance from the founding era, we generally determine whether to
exempt a given type of search from the warrant requirement
“by assessing, on the one hand, the degree to which it
intrudes upon an individual’s privacy and, on the other, the
degree to which it is needed for the promotion of legitimate
governmental interests.” Wyoming v. Houghton, 526 U. S.
295, 300 (1999) . Such a balancing of interests supported the
search incident to arrest exception in Robinson, and a mechanical
application of Robinson might well support the warrantless searches
at issue here.
But while
Robinson’s categorical rule strikes the appropriate balance
in the context of physical objects, neither of its rationales has
much force with respect to digital content on cell phones. On the
government interest side, Robinson concluded that the two risks
identified in Chimel—harm to officers and destruction of
evidence—are present in all custodial arrests. There are no
comparable risks when the search is of digital data. In addition,
Robinson regarded any privacy interests retained by an individual
after arrest as significantly diminished by the fact of the arrest
itself. Cell phones, however, place vast quantities of personal
information literally in the hands of individuals. A search of the
information on a cell phone bears little resemblance to the type of
brief physical search considered in Robinson.
We therefore decline to
extend Robinson to searches of data on cell phones, and hold
instead that officers must generally secure a warrant before
conducting such a search.
A
We first consider
each Chimel concern in turn. In doing so, we do not overlook
Robinson’s admonition that searches of a person incident to
arrest, “while based upon theneed to disarm and to discover
evidence,” are reasonable regardless of “the
probability in a particular arrest situation that weapons or
evidence would in fact be found.” 414 U. S., at 235. Rather
than requiring the “case-by-case adjudication” that
Robinson rejected, ibid., we ask instead whether application of the
search incident to arrest doctrine to this particular category of
effects would “untether the rule from the justifications
underlying the Chimel exception,” Gant, supra, at 343. See
also Knowles v. Iowa, 525 U. S. 113, 119 (1998) (declining to
extend Robinson to the issuance of citations, “a situation
where the concern for officer safety is not present to the same
extent and the concern for destruction or loss of evidence is not
present at all”).
1
Digital data stored
on a cell phone cannot itself be used as a weapon to harm an
arresting officer or to effectuate the arrestee’s escape. Law
enforcement officers remain free to examine the physical aspects of
a phone to ensure that it will not be used as a weapon—say,
to determine whether there is a razor blade hidden between the
phone and its case. Once an officer has secured a phone and
eliminated any potential physical threats, however, data on the
phone can endanger no one.
Perhaps the same might
have been said of the cigarette pack seized from Robinson’s
pocket. Once an officer gained control of the pack, it was unlikely
that Robinson could have accessed the pack’s contents. But
unknown physical objects may always pose risks, no matter how
slight, during the tense atmosphere of a custodial arrest. The
officer in Robinson testified that he could not identify the
objects in the cigarette pack but knew they were not cigarettes.
See 414 U. S., at 223, 236, n. 7. Given that, a further search
was a reasonable protective measure. No such unknowns exist with
respect to digital data. As the First Circuit explained, the
officers who searched Wurie’s cell phone “knew exactly
what they would find therein: data. They also knew that the data
could not harm them.” 728 F. 3d, at 10.
The United States and
California both suggest that a search of cell phone data might help
ensure officer safety in more indirect ways, for example by
alerting officers that confederates of the arrestee are headed to
the scene. There is undoubtedly a strong government interest in
warning officers about such possibilities, but neither the United
States nor California offers evidence to suggest that their
concerns are based on actual experience. The proposed consideration
would also represent a broadening of Chimel’s concern that an
arrestee himself might grab a weapon and use it against an officer
“to resist arrest or effect his escape.” 395
U. S., at 763. And any such threats from outside the arrest
scene do not “lurk[ ] in all custodial arrests.”
Chadwick, 433 U. S., at 14–15. Accordingly, the interest
in protecting officer safety does not justify dispensing with the
warrant requirement across the board. To the extent dangers to
arresting officers may be implicated in a particular way in a
particular case, they are better addressed through consideration of
case-specific exceptions to the warrant requirement, such as the
one for exigent circumstances. See, e.g., Warden, Md. Penitentiary
v. Hayden, 387 U. S. 294 –299 (1967) (“The Fourth
Amendment does not require police officers to delay in the course
of an investigation if to do so would gravely endanger their lives
or the lives of others.”).
2
The United States and
California focus primarily on the second Chimel rationale:
preventing the destruction of evidence.
Both Riley and Wurie
concede that officers could have seized and secured their cell
phones to prevent destruction of evidence while seeking a warrant.
See Brief for Petitioner in No. 13–132, p. 20; Brief for
Respondent in No. 13–212, p. 41. That is a sensible
concession. See Illinois v. McArthur, 531 U. S. 326 –333
(2001); Chadwick, supra, at 13, and n. 8. And once law enforcement
officers have secured a cell phone, there is no longer any risk
that the arrestee himself will be able to delete incriminating data
from the phone.
The United States and
California argue that information on a cell phone may nevertheless
be vulnerable to two types of evidence destruction unique to
digital data—remote wiping and data encryption. Remote wiping
occurs when a phone, connected to a wireless network, receives a
signal that erases stored data. This can happen when a third party
sends a remote signal or when a phone is preprogrammed to delete
data upon entering or leaving certain geographic areas (so-called
“geofencing”). See Dept. of Commerce, National
Institute of Standards and Technology, R. Ayers, S. Brothers, &
W. Jansen, Guidelines on Mobile Device Forensics (Draft) 29, 31 (SP
800–101 Rev. 1, Sept. 2013) (hereinafter Ayers). Encryption
is a security feature that some modern cell phones use in addition
to password protection. When such phones lock, data becomes
protected by sophisticated encryption that renders a phone all but
“unbreakable” unless police know the password. Brief
for United States as Amicus Curiae in No. 13–132, p. 11.
As an initial matter,
these broader concerns about the loss of evidence are distinct from
Chimel’s focus on a defendant who responds to arrest by
trying to conceal or destroy evidence within his reach. See 395
U. S., at 763–764. With respect to remote wiping, the
Government’s primary concern turns on the actions of third
parties who are not present at the scene of arrest. And data
encryption is even further afield. There, the Government focuses on
the ordinary operation of a phone’s security features, apart
from any active attempt by a defendant or his associates to conceal
or destroy evidence upon arrest.
We have also been given
little reason to believe that either problem is prevalent. The
briefing reveals only a couple of anecdotal examples of remote
wiping triggered by an arrest. See Brief for Association of State
Criminal Investigative Agencies et al. as Amici Curiae in No.
13–132, pp. 9–10; see also Tr. of Oral Arg. in No.
13–132,p. 48. Similarly, the opportunities for officers to
search a password-protected phone before data becomes encrypted are
quite limited. Law enforcement officers are very unlikely to come
upon such a phone in an unlocked state because most phones lock at
the touch of a button or, as a default, after some very short
period of inactivity. See, e.g., iPhone User Guide for iOS 7.1
Software 10 (2014) (default lock after about one minute). This may
explain why the encryption argument was not made until the merits
stage in this Court, and has never been considered by the Courts of
Appeals.
Moreover, in situations
in which an arrest might trigger a remote-wipe attempt or an
officer discovers an unlocked phone, it is not clear that the
ability to conduct a warrantless search would make much of a
difference. The need to effect the arrest, secure the scene, and
tend to other press-ing matters means that law enforcement officers
may well not be able to turn their attention to a cell phone right
away. See Tr. of Oral Arg. in No. 13–132, at 50; see also
Brief for United States as Amicus Curiae in No. 13–132, at
19. Cell phone data would be vulnerable to remote wiping from the
time an individual anticipates arrest to the time any eventual
search of the phone is completed, which might be at the station
house hours later. Likewise, an officer who seizes a phone in an
unlocked state might not be able to begin his search in the short
time remaining before the phone locks and data becomes
encrypted.
In any event, as to
remote wiping, law enforcement is not without specific means to
address the threat. Remote wiping can be fully prevented by
disconnecting a phone from the network. There are at least two
simple ways to do this: First, law enforcement officers can turn
the phone off or remove its battery. Second, if they are concerned
about encryption or other potential problems, they can leave a
phone powered on and place it in an enclosure that isolates the
phone from radio waves. See Ayers 30–31. Such devices are
commonly called “Faraday bags,” after the English
scientist Michael Faraday. They are essentially sandwich bags made
of aluminum foil: cheap, lightweight, and easy to use. See Brief
for Criminal Law Professors as Amici Curiae 9. They may not be a
complete answer to the problem, see Ayers 32, but at least for now
they provide a reasonable response. In fact, a number of law
enforcement agencies around the country already encourage the use
of Faraday bags. See, e.g., Dept. of Justice, National Institute of
Justice, Electronic Crime Scene Investigation: A Guide for First
Responders 14, 32 (2d ed. Apr. 2008); Brief for Criminal Law
Professors as Amici Curiae 4–6.
To the extent that law
enforcement still has specific concerns about the potential loss of
evidence in a particular case, there remain more targeted ways to
address those concerns. If “the police are truly confronted
with a ‘now or never’ situation,”—for
example, circumstances suggesting that a defendant’s phone
will be the target of an imminent remote-wipe attempt—they
may be able to rely on exigent circumstances to search the phone
immediately. Missouri v. McNeely, 569 U. S. ___, ___ (2013)
(slip op., at 10) (quoting Roaden v. Kentucky, 413 U. S. 496,
505 (1973) ; some internal quotation marks omitted). Or, if
officers happen to seize a phone in an unlocked state, they may be
able to disable a phone’s automatic-lock feature in order to
prevent the phone from locking and encrypting data. See App. to
Reply Brief in No. 13–132, p. 3a (diagramming the few
necessary steps). Such a preventive measure could be analyzed under
the principles set forth in our decision in McArthur, 531
U. S. 326 , which approved officers’ reasonable steps to
secure a scene to preserve evidence while they awaited a warrant.
See id., at 331–333.
B
The search incident
to arrest exception rests not only on the heightened government
interests at stake in a volatile arrest situation, but also on an
arrestee’s reduced privacy interests upon being taken into
police custody. Robinson focused primarily on the first of those
rationales. But it also quoted with approval then-Judge
Cardozo’s account of the historical basis for the search
incident to arrest exception: “Search of the person becomes
lawful when grounds for arrest and accusation have been discovered,
and the law is in the act of subjecting the body of the accused to
its physical dominion.” 414 U. S., at 232 (quoting
People v. Chiagles, 237 N. Y. 193, 197, 142 N. E. 583,
584 (1923)); see also 414 U. S., at 237 (Powell, J.,
concurring) (“an individual lawfully subjected to a custodial
arrest retains no significant Fourth Amendment interest in the
privacy of his person”). Put simply, a patdown of
Robinson’s cloth-ing and an inspection of the cigarette pack
found in his pocket constituted only minor additional intrusions
compared to the substantial government authority exercised in
taking Robinson into custody. See Chadwick, 433 U. S., at 16,
n. 10 (searches of a person are justified in part by
“reduced expectations of privacy caused by the
arrest”).
The fact that an
arrestee has diminished privacy interests does not mean that the
Fourth Amendment falls out of the picture entirely. Not every
search “is acceptable solely because a person is in
custody.” Maryland v. King, 569 U. S. ___, ___ (2013)
(slip op., at 26). To the contrary, when “privacy-related
concerns are weighty enough” a “search may require a
warrant, notwithstanding the diminished expectations of privacy of
the arrestee.” Ibid. One such example, of course, is Chimel.
Chimel refused to “characteriz[e] the invasion of privacy
that results from a top-to-bottom search of a man’s house as
‘minor.’ ” 395 U. S., at 766–767,
n. 12. Because a search of the arrestee’s entire house was a
substantial invasion beyond the arrest itself, the Court concluded
that a warrant was required.
Robinson is the only
decision from this Court applying Chimel to a search of the
contents of an item found on an arrestee’s person. In an
earlier case, this Court had approved a search of a zipper bag
carried by an arrestee, but the Court analyzed only the validity of
the arrest itself. See Draper v. United States, 358 U. S. 307
–311 (1959). Lower courts applying Robinson and Chimel,
however, have approved searches of a variety of personal items
carried by an arrestee. See, e.g., United States v. Carrion, 809
F. 2d 1120, 1123, 1128 (CA5 1987) (billfold and address book);
United States v. Watson, 669 F. 2d 1374, 1383–1384 (CA11
1982) (wallet); United States v. Lee, 501 F. 2d 890, 892 (CADC
1974) (purse).
The United States
asserts that a search of all data stored on a cell phone is
“materially indistinguishable” from searches of these
sorts of physical items. Brief for United States in No.
13–212, p. 26. That is like saying a ride on horseback is
materially indistinguishable from a flight to the moon. Both are
ways of getting from point A to point B, but little else justifies
lumping them together. Modern cell phones, as a category, implicate
privacy concerns far beyond those implicated by the search of a
cigarette pack, a wallet, or a purse. A conclusion that inspecting
the contents of an arrestee’s pockets works no substantial
additional intrusion on privacy beyond the arrest itself may make
sense as applied to physical items, but any extension of that
reasoning to digital data has to rest on its own bottom.
1
Cell phones differ in
both a quantitative and a qualitative sense from other objects that
might be kept on an arrestee’s person. The term “cell
phone” is itself misleading shorthand; many of these devices
are in fact minicomputers that also happen to have the capacity to
be used as a telephone. They could just as easily be called
cameras, video players, rolodexes, calendars, tape recorders,
libraries, diaries, albums, televisions, maps, or newspapers.
One of the most notable
distinguishing features of modern cell phones is their immense
storage capacity. Before cell phones, a search of a person was
limited by physical realities and tended as a general matter to
constitute only a narrow intrusion on privacy. See Kerr, Foreword:
Accounting for Technological Change, 36 Harv. J. L. & Pub.
Pol’y 403, 404–405 (2013). Most people cannot lug
around every piece of mail they have received for the past several
months, every picture they have taken, or every book or article
they have read—nor would they have any reason to attempt to
do so. And if they did, they would have to drag behind them a trunk
of the sort held to require a search warrant in Chadwick, supra,
rather than a container the size of the cigarette package in
Robinson.
But the possible
intrusion on privacy is not physically limited in the same way when
it comes to cell phones. The current top-selling smart phone has a
standard capacity of 16 gigabytes (and is available with up to 64
gigabytes). Sixteen gigabytes translates to millions of pages of
text, thousands of pictures, or hundreds of videos. See Kerr,
supra, at 404; Brief for Center for Democracy & Technol-ogy
et al. as Amici Curiae 7–8. Cell phones couple that
capacity with the ability to store many different types of
information: Even the most basic phones that sell for less than $20
might hold photographs, picture messages, text messages, Internet
browsing history, a calendar, a thousand-entry phone book, and so
on. See id., at 30; United States v. Flores-Lopez, 670 F. 3d
803, 806 (CA7 2012). We expect that the gulf between physical
practicability and digital capacity will only continue to widen in
the future.
The storage capacity of
cell phones has several interrelated consequences for privacy.
First, a cell phone collects in one place many distinct types of
information—an address, a note, a prescription, a bank
statement, a video—that reveal much more in combination than
any isolated record. Second, a cell phone’s capacity allows
even just one type of information to convey far more than
previously possible. The sum of an individual’s private life
can be reconstructed through a thousand photographs labeled with
dates, locations, and descriptions; the same cannot be said of a
photograph or two of loved ones tucked into a wallet. Third, the
data on a phone can date back to the purchase of the phone, or even
earlier. A person might carry in his pocket a slip of paper
reminding him to call Mr. Jones; he would not carry a record of all
his communications with Mr. Jones for the past several months, as
would routinely be kept on a phone.[
1]
Finally, there is an
element of pervasiveness that characterizes cell phones but not
physical records. Prior to the digital age, people did not
typically carry a cache of sensitive personal information with them
as they went about their day. Now it is the person who is not
carrying a cell phone, with all that it contains, who is the
exception. According to one poll, nearly three-quarters of smart
phone users report being within five feet of their phones most of
the time, with 12% admitting that they even use their phones in the
shower. See Harris Interactive, 2013 Mobile Consumer Habits Study
(June 2013). A decade ago police officers searching an arrestee
might have occasionally stumbled across a highly personal item such
as a diary. See, e.g., United States v. Frankenberry, 387
F. 2d 337 (CA2 1967) (per curiam). But those discoveries were
likely to be few and far between. Today, by contrast, it is no
exaggeration to say that many of the more than 90% of American
adults who own a cell phone keep on their person a digital record
of nearly every aspect of their lives—from the mundane to the
intimate. See Ontario v. Quon, 560 U. S. 746, 760 (2010) .
Allowing the police to scrutinize such records on a routine basis
is quite different from allowing them to search a personal item or
two in the occasional case.
Although the data
stored on a cell phone is distinguished from physical records by
quantity alone, certain types of data are also qualitatively
different. An Internet search and browsing history, for example,
can be found on an Internet-enabled phone and could reveal an
individual’s private interests or concerns—perhaps a
search for certain symptoms of disease, coupled with frequent
visits to WebMD. Data on a cell phone can also reveal where a
person has been. Historic location information is a stand-ard
feature on many smart phones and can reconstruct someone’s
specific movements down to the minute, not only around town but
also within a particular building. See United States v. Jones, 565
U. S. ___, ___ (2012) (Sotomayor, J., concurring) (slip op.,
at 3) (“GPS monitoring generates a precise, comprehensive
record of a person’s public movements that reflects a wealth
of detail about her familial, political, professional, religious,
and sexual associations.”).
Mobile application
software on a cell phone, or “apps,” offer a range of
tools for managing detailed information about all aspects of a
person’s life. There are apps for Democratic Party news and
Republican Party news; apps for alcohol, drug, and gambling
addictions; apps for sharing prayer requests; apps for tracking
pregnancy symptoms; apps for planning your budget; apps for every
conceivable hobby or pastime; apps for improving your romantic
life. There are popular apps for buying or selling just about
anything, and the records of such transactions may be accessible on
the phone indefinitely. There are over a million apps available in
each of the two major app stores; the phrase “there’s
an app for that” is now part of the popular lexicon. The
average smart phone user has installed 33 apps, which together can
form a revealing montage of the user’s life. See Brief for
Electronic Privacy Information Center as Amicus Curiae in No.
13–132, p. 9.
In 1926, Learned Hand
observed (in an opinion later quoted in Chimel) that it is “a
totally different thing to search a man’s pockets and use
against him what they contain, from ransacking his house for
everything which may incriminate him.” United States v.
Kirschenblatt, 16 F. 2d 202, 203 (CA2). If his pockets contain
a cell phone, however, that is no longer true. Indeed, a cell phone
search would typically expose to the government far more than the
most exhaustive search of a house: A phone not only contains in
digital form many sensitive records previ-ously found in the home;
it also contains a broad array of private information never found
in a home in any form—unless the phone is.
2
To further complicate
the scope of the privacy interests at stake, the data a user views
on many modern cell phones may not in fact be stored on the device
itself. Treating a cell phone as a container whose contents may be
searched incident to an arrest is a bit strained as an initial
matter. See New York v. Belton, 453 U. S. 454, 460, n. 4
(1981) (describing a “container” as “any object
capable of holding another object”). But the analogy crumbles
entirely when a cell phone is used to access data located
elsewhere, at the tap of a screen. That is what cell phones, with
increasing frequency, are designed to do by taking advantage of
“cloud computing.” Cloud computing is the capacity of
Internet-connected devices to display data stored on remote servers
rather than on the device itself. Cell phone users often may not
know whether particular information is stored on the device or in
the cloud, and it generally makes little difference. See Brief for
Electronic Privacy Information Center in No. 13–132, at
12–14, 20. Moreover, the same type of data may be stored
locally on the device for one user and in the cloud for
another.
The United States
concedes that the search incident to arrest exception may not be
stretched to cover a search of files accessed remotely—that
is, a search of files stored in the cloud. See Brief for United
States in No. 13–212, at 43–44. Such a search would be
like finding a key in a suspect’s pocket and arguing that it
allowed law enforcement to unlock and search a house. But officers
searching a phone’s data would not typically know whether the
information they are viewing was stored locally at the time of the
arrest or has been pulled from the cloud.
Although the Government
recognizes the problem, its proposed solutions are unclear. It
suggests that officers could disconnect a phone from the network
before searching the device—the very solution whose
feasibility it contested with respect to the threat of remote
wiping. Compare Tr. of Oral Arg. in No. 13–132, at
50–51, with Tr. of Oral Arg. in No. 13–212, pp.
13–14. Alternatively, the Government proposes that law
enforcement agencies “develop protocols to address”
concerns raised by cloud computing. Reply Brief in No.
13–212, pp. 14–15. Probably a good idea, but the
Founders did not fight a revolution to gain the right to government
agency protocols. The possibility that a search might extend well
beyond papers and effects in the physical proximity of an arrestee
is yet another reason that the privacy interests here dwarf those
in Robinson.
C
Apart from their
arguments for a direct extension of Robinson, the United States and
California offer various fallback options for permitting
warrantless cell phone searches under certain circumstances. Each
of the proposals is flawed and contravenes our general preference
to provide clear guidance to law enforcement through categorical
rules. “[I]f police are to have workable rules, the balancing
of the competing interests . . . ‘must in large
part be done on a categorical basis—not in an ad hoc,
case-by-case fashion by individual police
officers.’ ” Michigan v. Summers, 452 U. S.
692, 705, n. 19 (1981) (quoting Dunaway v. New York, 442 U. S.
200 –220 (1979) (White, J., concurring)).
The United States first
proposes that the Gant standard be imported from the vehicle
context, allowing a warrantless search of an arrestee’s cell
phone whenever it is reasonable to believe that the phone contains
evidence of the crime of arrest. But Gant relied on
“circumstances unique to the vehicle context” to
endorse a search solely for the purpose of gathering evidence. 556
U. S., at 343. Justice Scalia’s Thornton opinion, on
which Gant was based, explained that those unique circumstances are
“a reduced expectation of privacy” and
“heightened law enforcement needs” when it comes to
motor vehicles. 541 U. S., at 631; see also Wyoming v.
Houghton, 526 U. S., at 303–304. For reasons that we
have explained, cell phone searches bear neither of those
characteristics.
At any rate, a Gant
standard would prove no practical limit at all when it comes to
cell phone searches. In the vehicle context, Gant generally
protects against searches for evidence of past crimes. See 3 W.
LaFave, Search and Seizure §7.1(d), at 709, and n. 191. In the
cell phone context, however, it is reasonable to expect that
incriminating information will be found on a phone regardless of
when the crime occurred. Similarly, in the vehicle context Gant
restricts broad searches resulting from minor crimes such as
traffic violations. See id., §7.1(d), at 713, and n. 204. That
would not necessarily be true for cell phones. It would be a
particularly inexperienced or unimaginative law enforcement officer
who could not come up with sev-eral reasons to suppose evidence of
just about any crime could be found on a cell phone. Even an
individual pulled over for something as basic as speeding might
well have locational data dispositive of guilt on his phone. An
individual pulled over for reckless driving might have evidence on
the phone that shows whether he was texting while driving. The
sources of potential pertinent information are virtually unlimited,
so applying the Gant standard to cell phones would in effect give
“police officers unbridled discretion to rummage at will
among a person’s private effects.” 556 U. S., at
345.
The United States also
proposes a rule that would restrict the scope of a cell phone
search to those areas of the phone where an officer reasonably
believes that infor-mation relevant to the crime, the
arrestee’s identity, or officer safety will be discovered.
See Brief for United States in No. 13–212, at 51–53.
This approach would again impose few meaningful constraints on
officers. The proposed categories would sweep in a great deal of
information, and officers would not always be able to discern in
advance what information would be found where.
We also reject the
United States’ final suggestion that officers should always
be able to search a phone’s call log, as they did in
Wurie’s case. The Government relies on Smith v. Maryland, 442
U. S. 735 (1979) , which held that no warrant was required to
use a pen register at telephone company premises to identify
numbers dialed by a particular caller. The Court in that case,
however, concluded that the use of a pen register was not a
“search” at all under the Fourth Amendment. See id., at
745–746. There is no dispute here that the officers engaged
in a search of Wurie’s cell phone. Moreover, call logs
typically contain more than just phone numbers; they include any
identifying information that an individual might add, such as the
label “my house” in Wurie’s case.
Finally, at oral
argument California suggested a different limiting principle, under
which officers could search cell phone data if they could have
obtained the same information from a pre-digital counterpart. See
Tr. of Oral Arg. in No. 13–132, at 38–43; see also
Flores-Lopez, 670 F. 3d, at 807 (“If police are entitled
to open a pocket diary to copy the owner’s address, they
should be entitled to turn on a cell phone to learn its
number.”). But the fact that a search in the pre-digital era
could have turned up a photograph or two in a wallet does not
justify a search of thousands of photos in a digital gallery. The
fact that someone could have tucked a paper bank statement in a
pocket does not justify a search of every bank statement from the
last five years. And to make matters worse, such an analogue test
would allow law enforcement to search a range of items contained on
a phone, even though people would be unlikely to carry such a
variety of information in physical form. In Riley’s case, for
example, it is implausible that he would have strolled around with
video tapes, photo albums, and an address book all crammed into his
pockets. But because each of those items has a pre-digital
analogue, police under California’s proposal would be able to
search a phone for all of those items—a significant
diminution of privacy.
In addition, an
analogue test would launch courts on a difficult line-drawing
expedition to determine which digital files are comparable to
physical records. Is an e-mail equivalent to a letter? Is a
voicemail equivalent to a phone message slip? It is not clear how
officers could make these kinds of decisions before conducting a
search, or how courts would apply the proposed rule after the fact.
An analogue test would “keep defendants and judges guessing
for years to come.” Sykes v. United States, 564 U. S. 1
, ___ (2011) (Scalia, J., dissenting) (slip op., at 7) (discussing
the Court’s analogue test under the Armed Career Criminal
Act).
IV
We cannot deny that
our decision today will have an impact on the ability of law
enforcement to combat crime. Cell phones have become important
tools in facilitating coordination and communication among members
of criminal enterprises, and can provide valuable incriminating
information about dangerous criminals. Privacy comes at a cost.
Our holding, of course,
is not that the information on a cell phone is immune from search;
it is instead that a warrant is generally required before such a
search, even when a cell phone is seized incident to arrest. Our
cases have historically recognized that the warrant requirement is
“an important working part of our machinery of
gov-ernment,” not merely “an inconvenience to be
somehow ‘weighed’ against the claims of police
efficiency.” Coolidge v. New Hampshire, 403 U. S. 443,
481 (1971) . Recent technological advances similar to those
discussed here have, in addition, made the process of obtaining a
warrant itself more efficient. See McNeely, 569 U. S., at ___
(slip op., at 11–12); id., at ___ (Roberts, C. J.,
concurring in part and dissenting in part) (slip op., at 8)
(describing jurisdiction where “police officers can e-mail
warrant requests to judges’ iPads [and] judges have signed
such warrants and e-mailed them back to officers in less than 15
minutes”).
Moreover, even though
the search incident to arrest exception does not apply to cell
phones, other case-specific exceptions may still justify a
warrantless search of a particular phone. “One
well-recognized exception applies when ‘ “the
exigencies of the situation” make the needs of law
enforcement so compelling that [a] warrantless search is
objectively reasonable under the Fourth
Amendment.’ ” Kentucky v. King, 563 U. S., at
___ (slip op., at 6) (quoting Mincey v. Arizona, 437 U. S.
385, 394 (1978) ). Such exigencies could include the need to
prevent the imminent destruction of evidence in individual cases,
to pursue a fleeing suspect, and to assist persons who are
seriously injured or are threatened with imminent injury. 563
U. S., at ___. In Chadwick, for example, the Court held that
the exception for searches incident to arrest did not justify a
search of the trunk at issue, but noted that “if officers
have reason to believe that luggage contains some immediately
dangerous instrumentality, such as explosives, it would be
foolhardy to transport it to the station house without opening the
luggage.” 433 U. S., at 15, n. 9.
In light of the
availability of the exigent circumstances exception, there is no
reason to believe that law enforcement officers will not be able to
address some of the more extreme hypotheticals that have been
suggested: a suspect texting an accomplice who, it is feared, is
preparing to detonate a bomb, or a child abductor who may have
information about the child’s location on his cell phone. The
defendants here recognize—indeed, they stress—that such
fact-specific threats may justify a warrantless search of cell
phone data. See Reply Brief in No. 13–132, at 8–9;
Brief for Respondent in No. 13–212, at 30, 41. The critical
point is that, unlike the search incident to arrest exception, the
exigent circumstances exception requires a court to examine whether
an emergency justified a warrantless search in each particular
case. See McNeely, supra, at ___ (slip op., at 6).[
2]
* * *
Our cases have
recognized that the Fourth Amendment was the founding
generation’s response to the reviled “general
warrants” and “writs of assistance” of the
colonial era, which allowed British officers to rummage through
homes in an unrestrained search for evidence of criminal activity.
Opposition to such searches was in fact one of the driving forces
behind the Revolution itself. In 1761, the patriot James Otis
delivered a speech in Boston denouncing the use of writs of
assistance. A young John Adams was there, and he would later write
that “[e]very man of a crowded audience appeared to me to go
away, as I did, ready to take arms against writs of
assistance.” 10 Works of John Adams 247–248 (C. Adams
ed. 1856). According to Adams, Otis’s speech was “the
first scene of the first act of opposition to the arbitrary claims
of Great Britain. Then and there the child Independence was
born.” Id., at 248 (quoted in Boyd v. United States, 116
U. S. 616, 625 (1886) ).
Modern cell phones are
not just another technological convenience. With all they contain
and all they may reveal, they hold for many Americans “the
privacies of life,” Boyd, supra, at 630. The fact that
technology now allows an individual to carry such information in
his hand does not make the information any less worthy of the
protection for which the Founders fought. Our answer to the
question of what police must do before searching a cell phone
seized incident to an arrest is accordingly simple—get a
warrant.
We reverse the judgment
of the California Court of Appeal in No. 13–132 and remand
the case for further proceedings not inconsistent with this
opinion. We affirm the judgment of the First Circuit in No.
13–212.
It is so ordered.
