(Slip Opinion)
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` OCTOBER TERM, 2011
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`Syllabus
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`1
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` NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
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` being done in connection with this case, at the time the opinion is issued.
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`
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` The syllabus constitutes no part of the opinion of the Court but has been
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` prepared by the Reporter of Decisions for the convenience of the reader.
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` See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
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`SUPREME COURT OF THE UNITED STATES
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`
` Syllabus
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` UNITED STATES v. JONES
`
`CERTIORARI TO THE UNITED STATES COURT OF APPEALS FOR
`
`THE DISTRICT OF COLUMBIA CIRCUIT
` No. 10–1259. Argued November 8, 2011—Decided January 23, 2012
`
`The Government obtained a search warrant permitting it to install a
`Global-Positioning-System (GPS) tracking device on a vehicle regis-
`tered to respondent Jones’s wife. The warrant authorized installa-
`tion in the District of Columbia and within 10 days, but agents in-
`stalled the device on the 11th day and in Maryland. The Government
`then tracked the vehicle’s movements for 28 days. It subsequently
`secured an indictment of Jones and others on drug trafficking con-
`spiracy charges. The District Court suppressed the GPS data ob-
`tained while the vehicle was parked at Jones’s residence, but held the
`remaining data admissible because Jones had no reasonable expecta-
`tion of privacy when the vehicle was on public streets. Jones was
`convicted. The D. C. Circuit reversed, concluding that admission of
`the evidence obtained by warrantless use of the GPS device violated
`the Fourth Amendment.
`Held: The Government’s attachment of the GPS device to the vehicle,
`and its use of that device to monitor the vehicle’s movements, consti-
`tutes a search under the Fourth Amendment. Pp. 3–12.
`
`
`(a) The Fourth Amendment protects the “right of the people to be
`secure in their persons, houses, papers, and effects, against unrea-
`sonable searches and seizures.” Here, the Government’s physical in-
`trusion on an “effect” for the purpose of obtaining information consti-
`
`tutes a “search.” This type of encroachment on an area enumerated
`in the Amendment would have been considered a search within the
`meaning of the Amendment at the time it was adopted. Pp. 3–4.
`
`(b) This conclusion is consistent with this Court’s Fourth Amend-
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`ment jurisprudence, which until the latter half of the 20th century
`
`was tied to common-law trespass. Later cases, which have deviated
`from that exclusively property-based approach, have applied the
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`UNITED STATES v. JONES
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`Syllabus
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`analysis of Justice Harlan’s concurrence in Katz v. United States, 389
`
`U. S. 347, which said that the Fourth Amendment protects a person’s
`“reasonable expectation of privacy,” id., at 360. Here, the Court need
`not address the Government’s contention that Jones had no “reason-
`
`able expectation of privacy,” because Jones’s Fourth Amendment
`rights do not rise or fall with the Katz formulation. At bottom, the
`Court must “assur[e] preservation of that degree of privacy against
`government that existed when the Fourth Amendment was adopted.”
`Kyllo v. United States, 533 U. S. 27, 34. Katz did not repudiate the
`understanding that the Fourth Amendment embodies a particular
`concern for government trespass upon the areas it enumerates. The
`Katz reasonable-expectation-of-privacy test has been added to, but
`not substituted for, the common-law trespassory test. See Alderman
`v. United States, 394 U. S. 165, 176; Soldal v. Cook County, 506 U. S.
`56, 64. United States v. Knotts, 460 U. S. 276, and United States v.
`
`
`Karo, 468 U. S. 705—post-Katz cases rejecting Fourth Amendment
`challenges to “beepers,” electronic tracking devices representing an-
`other form of electronic monitoring—do not foreclose the conclusion
`that a search occurred here. New York v. Class, 475 U. S. 106, and
`
`
`Oliver v. United States, 466 U. S. 170, also do not support the Gov-
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`ernment’s position. Pp. 4–12.
`(c) The Government’s alternative argument—that if the attach-
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`ment and use of the device was a search, it was a reasonable one—is
`forfeited because it was not raised below. P. 12.
`615 F. 3d 544, affirmed.
`SCALIA, J., delivered the opinion of the Court, in which ROBERTS,
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`C. J., and KENNEDY, THOMAS, and SOTOMAYOR, JJ., joined. SOTOMAYOR,
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`J., filed a concurring opinion. ALITO, J., filed an opinion concurring in
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` the judgment, in which GINSBURG, BREYER, and KAGAN, JJ., joined.
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`Cite as: 565 U. S. ____ (2012)
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`Opinion of the Court
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`1
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` NOTICE: This opinion is subject to formal revision before publication in the
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` preliminary print of the United States Reports. Readers are requested to
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` notify the Reporter of Decisions, Supreme Court of the United States, Wash-
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` ington, D. C. 20543, of any typographical or other formal errors, in order
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` that corrections may be made before the preliminary print goes to press.
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`SUPREME COURT OF THE UNITED STATES
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`_________________
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` No. 10–1259
`_________________
`UNITED STATES, PETITIONER v. ANTOINE JONES
`ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
`
`
`
` APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT
`
`
`
`
`[January 23, 2012]
`
` JUSTICE SCALIA delivered the opinion of the Court.
`We decide whether the attachment of a Global-
`
`Positioning-System (GPS) tracking device to an individu-
`al’s vehicle, and subsequent use of that device to monitor
`the vehicle’s movements on public streets, constitutes a
`search or seizure within the meaning of the Fourth
`Amendment.
`
`
`
`I
`In 2004 respondent Antoine Jones, owner and operator
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`of a nightclub in the District of Columbia, came under
`suspicion of trafficking in narcotics and was made the
`target of an investigation by a joint FBI and Metropolitan
`Police Department task force. Officers employed various
`investigative techniques, including visual surveillance of
`the nightclub, installation of a camera focused on the front
`door of the club, and a pen register and wiretap covering
`Jones’s cellular phone.
`
`Based in part on information gathered from these
`
`sources, in 2005 the Government applied to the United
`States District Court for the District of Columbia for a
`warrant authorizing the use of an electronic tracking
`device on the Jeep Grand Cherokee registered to Jones’s
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`UNITED STATES v. JONES
`
`Opinion of the Court
` wife. A warrant issued, authorizing installation of the de-
`vice in the District of Columbia and within 10 days.
`On the 11th day, and not in the District of Columbia but
`
`in Maryland,1 agents installed a GPS tracking device on
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`the undercarriage of the Jeep while it was parked in a
`public parking lot. Over the next 28 days, the Govern-
`ment used the device to track the vehicle’s movements,
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`and once had to replace the device’s battery when the
`vehicle was parked in a different public lot in Maryland.
`
`By means of signals from multiple satellites, the device
`established the vehicle’s location within 50 to 100 feet, and
`communicated that location by cellular phone to a Gov-
`ernment computer. It relayed more than 2,000 pages of
`data over the 4-week period.
`
`The Government ultimately obtained a multiple-count
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`indictment charging Jones and several alleged co-
`conspirators with, as relevant here, conspiracy to distrib-
`
`ute and possess with intent to distribute five kilograms or
`more of cocaine and 50 grams or more of cocaine base, in
`
`violation of 21 U. S. C. §§841 and 846. Before trial, Jones
`filed a motion to suppress evidence obtained through the
`GPS device. The District Court granted the motion only in
`part, suppressing the data obtained while the vehicle was
`
`parked in the garage adjoining Jones’s residence. 451
`F. Supp. 2d 71, 88 (2006). It held the remaining data
`admissible, because “‘[a] person traveling in an automo-
`
`bile on public thoroughfares has no reasonable expectation
`of privacy in his movements from one place to another.’ ”
`Ibid. (quoting United States v. Knotts, 460 U. S. 276, 281
`(1983)). Jones’s trial in October 2006 produced a hung
`jury on the conspiracy count.
`
`In March 2007, a grand jury returned another indict-
`——————
`1In this litigation, the Government has conceded noncompliance with
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`the warrant and has argued only that a warrant was not required.
`United States v. Maynard, 615 F. 3d 544, 566, n. (CADC 2010).
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`2
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`3
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` Cite as: 565 U. S. ____ (2012)
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`Opinion of the Court
`ment, charging Jones and others with the same conspir-
`acy. The Government introduced at trial the same GPS-
`derived locational data admitted in the first trial, which
`connected Jones to the alleged conspirators’ stash house
`that contained $850,000 in cash, 97 kilograms of cocaine,
`and 1 kilogram of cocaine base. The jury returned a guilty
`verdict, and the District Court sentenced Jones to life
`imprisonment.
`The United States Court of Appeals for the District of
`
`Columbia Circuit reversed the conviction because of ad-
`mission of the evidence obtained by warrantless use of
`the GPS device which, it said, violated the Fourth Amend-
`ment. United States v. Maynard, 615 F. 3d 544 (2010).
`
`The D. C. Circuit denied the Government’s petition for
`rehearing en banc, with four judges dissenting. 625 F. 3d
`
`766 (2010). We granted certiorari, 564 U. S. ___ (2011).
`
`II
`
`
`
`
`A
`
`The Fourth Amendment provides in relevant part that
`
`“[t]he right of the people to be secure in their persons,
`houses, papers, and effects, against unreasonable searches
`
`and seizures, shall not be violated.” It is beyond dispute
`that a vehicle is an “effect” as that term is used in the
`Amendment. United States v. Chadwick, 433 U. S. 1, 12
`
`(1977). We hold that the Government’s installation of a
`GPS device on a target’s vehicle,2 and its use of that device
`to monitor the vehicle’s movements, constitutes a “search.”
`
`——————
`2As we have noted, the Jeep was registered to Jones’s wife. The Gov-
`ernment acknowledged, however, that Jones was “the exclusive driver.”
`
` Id., at 555, n. (internal quotation marks omitted). If Jones was not the
`owner he had at least the property rights of a bailee. The Court of
`Appeals concluded that the vehicle’s registration did not affect his
`ability to make a Fourth Amendment objection, ibid., and the Govern-
`ment has not challenged that determination here. We therefore do not
`
`consider the Fourth Amendment significance of Jones’s status.
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`4
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`UNITED STATES v. JONES
`
`Opinion of the Court
`It is important to be clear about what occurred in this
`
`case: The Government physically occupied private proper-
`ty for the purpose of obtaining information. We have no
`doubt that such a physical intrusion would have been
`considered a “search” within the meaning of the Fourth
`
`
`Amendment when it was adopted. Entick v. Carrington,
`95 Eng. Rep. 807 (C. P. 1765), is a “case we have described
`
`as a ‘monument of English freedom’ ‘undoubtedly familiar’
`to ‘every American statesman’ at the time the Constitution
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`was adopted, and considered to be ‘the true and ultimate
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`expression of constitutional law’” with regard to search
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`and seizure. Brower v. County of Inyo, 489 U. S. 593, 596
`(1989) (quoting Boyd v. United States, 116 U. S. 616, 626
`(1886)). In that case, Lord Camden expressed in plain
`terms the significance of property rights in search-and-
`seizure analysis:
`“[O]ur law holds the property of every man so sacred,
`that no man can set his foot upon his neighbour’s close
`without his leave; if he does he is a trespasser, though
`he does no damage at all; if he will tread upon his
`neighbour’s ground, he must justify it by law.” Entick,
`supra, at 817.
`The text of the Fourth Amendment reflects its close con-
`nection to property, since otherwise it would have referred
`simply to “the right of the people to be secure against
`unreasonable searches and seizures”; the phrase “in their
`persons, houses, papers, and effects” would have been
`superfluous.
`
`this understanding, our Fourth
`Consistent with
`
`Amendment jurisprudence was tied to common-law tres-
`pass, at least until the latter half of the 20th century.
`
`Kyllo v. United States, 533 U. S. 27, 31 (2001); Kerr, The
`Fourth Amendment and New Technologies: Constitutional
`Myths and the Case for Caution, 102 Mich. L. Rev. 801,
`816 (2004). Thus, in Olmstead v. United States, 277 U. S.
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`5
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`Cite as: 565 U. S. ____ (2012)
`
`Opinion of the Court
`438 (1928), we held that wiretaps attached to telephone
`wires on the public streets did not constitute a Fourth
`Amendment search because “[t]here was no entry of the
`houses or offices of the defendants,” id., at 464.
`Our later cases, of course, have deviated from that
`
`exclusively property-based approach. In Katz v. United
`States, 389 U. S. 347, 351 (1967), we said that “the Fourth
`Amendment protects people, not places,” and found a
`violation in attachment of an eavesdropping device to a
`public telephone booth. Our later cases have applied the
`analysis of Justice Harlan’s concurrence in that case,
`which said that a violation occurs when government offic-
`ers violate a person’s “reasonable expectation of privacy,”
`id., at 360. See, e.g., Bond v. United States, 529 U. S. 334
`(2000); California v. Ciraolo, 476 U. S. 207 (1986); Smith
`
`v. Maryland, 442 U. S. 735 (1979).
`The Government contends that the Harlan standard
`
`shows that no search occurred here, since Jones had no
`“reasonable expectation of privacy” in the area of the Jeep
`accessed by Government agents (its underbody) and in the
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`locations of the Jeep on the public roads, which were
`visible to all. But we need not address the Government’s
`contentions, because Jones’s Fourth Amendment rights
`
` do not rise or fall with the Katz formulation. At bottom,
`we must “assur[e] preservation of that degree of privacy
`against government that existed when the Fourth
`Amendment was adopted.” Kyllo, supra, at 34. As ex-
`plained, for most of our history the Fourth Amendment
`was understood to embody a particular concern for gov-
`ernment trespass upon the areas (“persons, houses, pa-
`pers, and effects”) it enumerates.3 Katz did not repudiate
`
`
`——————
`3 JUSTICE ALITO’s concurrence (hereinafter concurrence) doubts the
`wisdom of our approach because “it is almost impossible to think of
`late-18th-century situations that are analogous to what took place in
`this case.” Post, at 3 (opinion concurring in judgment). But in fact it
`posits a situation that is not far afield—a constable’s concealing himself
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`6
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`UNITED STATES v. JONES
`
`Opinion of the Court
`that understanding. Less than two years later the Court
`upheld defendants’ contention that the Government could
`not introduce against them conversations between other
`people obtained by warrantless placement of electronic
`surveillance devices in their homes. The opinion rejected
`the dissent’s contention that there was no Fourth
`Amendment violation “unless the conversational privacy of
`the homeowner himself is invaded.”4 Alderman v. United
`States, 394 U. S. 165, 176 (1969). “[W]e [do not] believe
`that Katz, by holding that the Fourth Amendment protects
`persons and their private conversations, was intended
`to withdraw any of the protection which the Amendment
`extends to the home . . . .” Id., at 180.
`More recently, in Soldal v. Cook County, 506 U. S. 56
`
`(1992), the Court unanimously rejected the argument that
`although a “seizure” had occurred “in a ‘technical’ sense”
`when a trailer home was forcibly removed, id., at 62, no
`Fourth Amendment violation occurred because law en-
`forcement had not “invade[d] the [individuals’] privacy,”
`id., at 60. Katz, the Court explained, established that
`
`“property rights are not the sole measure of Fourth
`
`——————
`in the target’s coach in order to track its movements. Ibid. There is no
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`doubt that the information gained by that trespassory activity would be
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`the product of an unlawful search—whether that information consisted
`of the conversations occurring in the coach, or of the destinations to
`which the coach traveled.
`
`
`
`In any case, it is quite irrelevant whether there was an 18th-century
`analog. Whatever new methods of investigation may be devised, our
`task, at a minimum, is to decide whether the action in question would
`have constituted a “search” within the original meaning of the Fourth
`
`
`Amendment. Where, as here, the Government obtains information by
`physically intruding on a constitutionally protected area, such a search
`
`has undoubtedly occurred.
`4Thus,the concurrence’s attempt to recast Alderman as meaning that
`individuals have a “legitimate expectation of privacy in all conversa-
`
`tions that [take] place under their roof,” post, at 6–7, is foreclosed by
`the Court’s opinion. The Court took as a given that the homeowner’s
`“conversational privacy” had not been violated.
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`Cite as: 565 U. S. ____ (2012)
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`Opinion of the Court
`Amendment violations,” but did not “snuf[f ] out the previ-
`ously recognized protection for property.” 506 U. S., at 64.
`As Justice Brennan explained in his concurrence in
`Knotts, Katz did not erode the principle “that, when the
`Government does engage in physical intrusion of a consti-
`tutionally protected area in order to obtain information,
`that intrusion may constitute a violation of the Fourth
`Amendment.” 460 U. S., at 286 (opinion concurring in
`
`judgment). We have embodied that preservation of past
`rights in our very definition of “reasonable expectation
`of privacy” which we have said to be an expectation “that
`has a source outside of the Fourth Amendment, either by
`reference to concepts of real or personal property law or
`to understandings that are recognized and permitted by
`society.” Minnesota v. Carter, 525 U. S. 83, 88 (1998)
`(internal quotation marks omitted). Katz did not narrow
`
`the Fourth Amendment’s scope.5
`
`The Government contends that several of our post-Katz
`cases foreclose the conclusion that what occurred here
`constituted a search. It relies principally on two cases in
`——————
`5The concurrence notes that post-Katz we have explained that “ ‘an
`
`actual trespass is neither necessary nor sufficient to establish a consti-
`
` tutional violation.’ ” Post, at 6 (quoting United States v. Karo, 468 U. S.
`
`705, 713 (1984)). That is undoubtedly true, and undoubtedly irrele-
`
` vant. Karo was considering whether a seizure occurred, and as the
`concurrence explains, a seizure of property occurs, not when there is a
`
` trespass, but “when there is some meaningful interference with an
`individual’s possessory interests in that property.” Post, at 2 (internal
`
`quotation marks omitted). Likewise with a search. Trespass alone
`does not qualify, but there must be conjoined with that what was
`present here: an attempt to find something or to obtain information.
`
`Related to this, and similarly irrelevant, is the concurrence’s point
`
`that, if analyzed separately, neither the installation of the device nor
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`its use would constitute a Fourth Amendment search. See ibid. Of
`
`course not. A trespass on “houses” or “effects,” or a Katz invasion of
`
`
`privacy, is not alone a search unless it is done to obtain information;
`and the obtaining of information is not alone a search unless it is
`achieved by such a trespass or invasion of privacy.
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`7
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`8
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`UNITED STATES v. JONES
`
`Opinion of the Court
`which we rejected Fourth Amendment challenges to
`“beepers,” electronic tracking devices that represent an-
`other form of electronic monitoring. The first case, Knotts,
`upheld against Fourth Amendment challenge the use of a
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`“beeper” that had been placed in a container of chloroform,
`allowing law enforcement to monitor the location of the
`container. 460 U. S., at 278. We said that there had been
`no infringement of Knotts’ reasonable expectation of pri-
`vacy since the information obtained—the location of the
`automobile carrying the container on public roads, and
`the location of the off-loaded container in open fields near
`Knotts’ cabin—had been voluntarily conveyed to the pub-
`lic.6 Id., at 281–282. But as we have discussed, the Katz
`
`reasonable-expectation-of-privacy test has been added to,
`not substituted for, the common-law trespassory test. The
`holding in Knotts addressed only the former, since the
`latter was not at issue. The beeper had been placed in
`the container before it came into Knotts’ possession, with
`the consent of the then-owner. 460 U. S., at 278. Knotts
`did not challenge that installation, and we specifically de-
`clined to consider its effect on the Fourth Amendment
`analysis. Id., at 279, n. Knotts would be relevant, per-
`haps, if the Government were making the argument that
`what would otherwise be an unconstitutional search is
`not such where it produces only public information. The
`Government does not make that argument, and we know
`of no case that would support it.
`
`The second “beeper” case, United States v. Karo, 468
`
`
`U. S. 705 (1984), does not suggest a different conclusion.
`There we addressed the question left open by Knotts,
`whether the installation of a beeper in a container
`——————
`
` 6 Knotts noted the “limited use which the government made of the
`signals from this particular beeper,” 460 U. S., at 284; and reserved the
`question whether “different constitutional principles may be applicable”
`to “dragnet-type law enforcement practices” of the type that GPS
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` tracking made possible here, ibid.
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`9
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`Opinion of the Court
`amounted to a search or seizure. 468 U. S., at 713. As in
`Knotts, at the time the beeper was installed the container
`belonged to a third party, and it did not come into posses-
`
`
`sion of the defendant until later. 468 U. S., at 708. Thus,
`the specific question we considered was whether the in-
`stallation “with the consent of the original owner consti-
`tute[d] a search or seizure . . . when the container is deliv-
`ered to a buyer having no knowledge of the presence of the
`beeper.” Id., at 707 (emphasis added). We held not. The
`Government, we said, came into physical contact with
`the container only before it belonged to the defendant Karo;
`and the transfer of the container with the unmonitored
`beeper inside did not convey any information and thus did
`not invade Karo’s privacy. See id., at 712. That conclu-
`
`sion is perfectly consistent with the one we reach here.
`Karo accepted the container as it came to him, beeper and
`all, and was therefore not entitled to object to the beeper’s
`presence, even though it was used to monitor the contain-
`er’s location. Cf. On Lee v. United States, 343 U. S. 747,
`751–752 (1952) (no search or seizure where an informant,
`who was wearing a concealed microphone, was invited into
`the defendant’s business). Jones, who possessed the Jeep
`at the time the Government trespassorily inserted the
`information-gathering device, is on much different footing.
`
`The Government also points to our exposition in New
`
`York v. Class, 475 U. S. 106 (1986), that “[t]he exterior of
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`a car . . . is thrust into the public eye, and thus to examine
`it does not constitute a ‘search.’” Id., at 114. That state-
`ment is of marginal relevance here since, as the Govern-
`
`ment acknowledges, “the officers in this case did more
`than conduct a visual inspection of respondent’s vehicle,”
`Brief for United States 41 (emphasis added). By attaching
`the device to the Jeep, officers encroached on a protected
`
`area. In Class itself we suggested that this would make a
`difference, for we concluded that an officer’s momentary
`reaching into the interior of a vehicle did constitute a
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`10
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`UNITED STATES v. JONES
`
`Opinion of the Court
`search.7 475 U. S., at 114–115.
`
`
`Finally, the Government’s position gains little support
`
`from our conclusion in Oliver v. United States, 466 U. S.
`170 (1984), that officers’ information-gathering intrusion
`on an “open field” did not constitute a Fourth Amendment
`search even though it was a trespass at common law, id.,
`at 183. Quite simply, an open field, unlike the curtilage of
`a home, see United States v. Dunn, 480 U. S. 294, 300
`(1987), is not one of those protected areas enumerated in
`
`the Fourth Amendment. Oliver, supra, at 176–177. See
`also Hester v. United States, 265 U. S. 57, 59 (1924). The
`Government’s physical intrusion on such an area—unlike
`its intrusion on the “effect” at issue here—is of no Fourth
`
`Amendment significance.8
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`B
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`The concurrence begins by accusing us of applying
`
`
`“18th-century tort law.” Post, at 1. That is a distortion.
`What we apply is an 18th-century guarantee against un-
`reasonable searches, which we believe must provide at
`——————
`7The Government also points to Cardwell v. Lewis, 417 U. S. 583
`(1974), in which the Court rejected the claim that the inspection of an
`impounded vehicle’s tire tread and the collection of paint scrapings
`from its exterior violated the Fourth Amendment. Whether the plural-
`
` ity said so because no search occurred or because the search was rea-
`sonable is unclear. Compare id., at 591 (opinion of Blackmun, J.)
`(“[W]e fail to comprehend what expectation of privacy was infringed”),
`with id., at 592 (“Under circumstances such as these, where probable
`
`cause exists, a warrantless examination of the exterior of a car is not
`
`unreasonable . . . ”).
`8Thus, our theory is not that the Fourth Amendment is concerned
`
` with “any technical trespass that led to the gathering of evidence.”
`Post, at 3 (ALITO, J., concurring in judgment) (emphasis added). The
`Fourth Amendment protects against trespassory searches only with
`
`regard to those items (“persons, houses, papers, and effects”) that it
`
`enumerates. The trespass that occurred in Oliver may properly be
`
`understood as a “search,” but not one “in the constitutional sense.” 466
`U. S., at 170, 183.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`

`
`
`
` Cite as: 565 U. S. ____ (2012)
`
`Opinion of the Court
`a minimum the degree of protection it afforded when it
`
`was adopted. The concurrence does not share that belief.
`
`
`It would apply exclusively Katz’s reasonable-expectation-
`
`of-privacy test, even when that eliminates rights that
`previously existed.
`
`The concurrence faults our approach for “present[ing]
`
`particularly vexing problems” in cases that do not involve
`physical contact, such as those that involve the transmis-
`sion of electronic signals. Post, at 9. We entirely fail to
`understand that point. For unlike the concurrence, which
`would make Katz the exclusive test, we do not make tres-
`
`pass the exclusive test. Situations involving merely the
`
`transmission of electronic signals without trespass would
`
`remain subject to Katz analysis.
`
`In fact, it is the concurrence’s insistence on the exclusiv-
`ity of the Katz test that needlessly leads us into “particu-
`larly vexing problems” in the present case. This Court has
`to date not deviated from the understanding that mere
`visual observation does not constitute a search. See Kyllo,
`533 U. S., at 31–32. We accordingly held in Knotts that
`“[a] person traveling in an automobile on public thorough-
`fares has no reasonable expectation of privacy in his
`
`movements from one place to another.” 460 U. S., at 281.
`Thus, even assuming that the concurrence is correct to
`say that “[t]raditional surveillance” of Jones for a 4-week
`period “would have required a large team of agents, multi-
`ple vehicles, and perhaps aerial assistance,” post, at 12,
`our cases suggest that such visual observation is constitu-
`tionally permissible. It may be that achieving the same
`result through electronic means, without an accompany-
`ing trespass, is an unconstitutional invasion of privacy,
`but the present case does not require us to answer that
`
`question.
`
`And answering it affirmatively leads us needlessly into
`additional thorny problems. The concurrence posits that
`“relatively short-term monitoring of a person’s movements
`
`
`
`
`
`
`
`
` 11
`
`
`
`
`
`
`
`
`
`

`
`12
`
`
`UNITED STATES v. JONES
`
`Opinion of the Court
`on public streets” is okay, but that “the use of longer term
`GPS monitoring in investigations of most offenses” is no
`good. Post, at 13 (emphasis added). That introduces yet
`another novelty into our jurisprudence. There is no prece-
`dent for the proposition that whether a search has oc-
`curred depends on the nature of the crime being investi-
`gated. And even accepting that novelty, it remains
`unexplained why a 4-week investigation is “surely” too
`long and why a drug-trafficking conspiracy involving sub-
`stantial amounts of cash and narcotics is not an “extra-
`ordinary offens[e]” which may permit longer observation.
`See post, at 13–14. What of a 2-day monitoring of a
`suspected purveyor of stolen electronics? Or of a 6-month
`monitoring of a suspected terrorist? We may have to
`grapple with these “vexing problems” in some future case
`where a classic trespassory search is not involved and
`resort must be had to Katz analysis; but there is no reason
`for rushing forward to resolve them here.
`III
`
`The Government argues in the alternative that even if
`
`the attachment and use of the device was a search, it was
`
`reasonable—and thus lawful—under the Fourth Amend-
`ment because “officers had reasonable suspicion, and in-
`deed probable cause, to believe that [Jones] was a leader
`in a large-scale cocaine distribution conspiracy.” Brief for
`United States 50–51. We have no occasion to consider this
`argument. The Government did not raise it below, and
`the D. C. Circuit therefore did not address it. See 625
`F. 3d, at 767 (Ginsburg, Tatel, and Griffith, JJ., concur-
`ring in denial of rehearing en banc). We consider the
`argument forfeited. See Sprietsma v. Mercury Marine, 537
`
`U. S. 51, 56, n. 4 (2002).
`*
`*
`*
`
`
`The judgment of the Court of Appeals for the D. C.
`
`Circuit is affirmed.
`
`
`
`
`
`
`
`
`
`
`
`It is so ordered.
`
`
`
`

`
`
`
`1
`
`Cite as: 565 U. S. ____ (2012)
`
`
` SOTOMAYOR, J., concurring
`
`
`SUPREME COURT OF THE UNITED STATES
`
`_________________
`
` No. 10–1259
`_________________
`UNITED STATES, PETITIONER v. ANTOINE JONES
`ON WRIT OF CERTIORARI TO THE UNITED STATES COURT OF
`
`
`
` APPEALS FOR THE DISTRICT OF COLUMBIA CIRCUIT
`
`
`
`
`[January 23, 2012]
`
`
` JUSTICE SOTOMAYOR, concurring.
`I join the Court’s opinion because I agree that a search
`
`within the meaning of the Fourth Amendment occurs, at a
`minimum, “[w]here, as here, the Government obtains
`information by physically intruding on a constitutionally
`
` protected area.” Ante, at 6, n. 3. In this case, the Gov-
`ernment installed a Global Positioning System (GPS)
`tracking device on respondent Antoine Jones’ Jeep without
`a valid warrant and without Jones’ consent, then used
`that device to monitor the Jeep’s movements over the
`course of four weeks. The Government usurped Jones’
`property for the purpose of conducting surveillance on
`him, thereby invading privacy interests long afforded, and
`
`undoubtedly entitled to, Fourth Amendment protection.
`
`See, e.g., Silverman v. United States, 365 U. S. 505, 511–
`512 (1961).
`
`Of course, the Fourth Amendment is not concerned only
`
`with trespassory intrusions on property. See, e.g., Kyllo v.
`
`United States, 533 U. S. 27, 31–33 (2001). Rather, even in
`the absence of a trespass, “a Fourth Amendment search
`occurs when the government violates a subjective expecta-
`
`
`tion of privacy that society recognizes as reasonable.” Id.,
`at 33; see also Smith v. Maryland, 442 U. S. 735, 740–741
`(1979); Katz v. United States, 389 U. S. 347, 361 (1967)
`(Harlan, J., concurring). In Katz, this Court enlarged its
`then-prevailing focus on property rights by announcing
`
`
`
`
`
`
`
`
`
`

`
`UNITED STATES v. JONES
`
` SOTOMAYOR, J., concurring
`
`
`that the reach of the Fourth Amendment does not “turn
`upon the presence or absence of a physical intrusion.” Id.,
`at 353. As the majority’s opinion makes clear, however,
`Katz’s reasonable-expectation-of-privacy test augmented,
`but did not displace or diminish, the common-law trespas-
`sory test that preceded it. Ante, at 8. Thus, “when the
`Government does engage in physical intrusion of a consti-
`tutionally protected area in order to obtain information,
`that intrusion may constitute a violation of the Fourth
`Amendment.” United States v. Knotts, 460 U. S. 276, 28