Katz and the Adoption of the Reasonable Expectation of Privacy Test

Amdt4.2.2.2 Katz and the Adoption of the Reasonable Expectation of Privacy Test

Fourth Amendment:

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.

The Court later adopted a new approach. “The premise that property interests control the right of the government to search and seize has been discredited. . . . We have recognized that the principal object of the Fourth Amendment is the protection of privacy rather than property, and have increasingly discarded fictional and procedural barriers rested on property concepts.” 1 Thus, because the Amendment “protects people, not places,” the requirement of actual physical trespass is dispensed with and electronic surveillance was made subject to the Amendment’s requirements.2

The new test, propounded in Katz v. United States, is whether there is an expectation of privacy upon which one may “justifiably” rely.3 “What a person knowingly exposes to the public, even in his own home or office, is not a subject of Fourth Amendment protection. But what he seeks to preserve as private, even in an area accessible to the public, may be constitutionally protected.” 4 That is, the “capacity to claim the protection of the Amendment depends not upon a property right in the invaded place but upon whether the area was one in which there was reasonable expectation of freedom from governmental intrusion.” 5

Katz’s focus on privacy was revitalized in Kyllo v. United States,6 in which the Court invalidated the warrantless use of a thermal imaging device directed at a private home from a public street. The rule devised by the Court to limit police use of new technology that can “shrink the realm of guaranteed privacy” is that “obtaining by sense-enhancing technology any information regarding the interior of the home that could not otherwise have been obtained without physical ‘intrusion into a constitutionally protected area’ . . . constitutes a search—at least where (as here) the technology in question is not in general public use.” 7 Relying on Katz, the Court rejected as “mechanical” the Government’s attempted distinction between off-the-wall and through-the-wall surveillance. Permitting all off-the-wall observations, the Court observed, “would leave the homeowner at the mercy of advancing technology—including technology that could discern all human activity in the home.” To some extent, the Court has grounded this concern about expectations of privacy in “Founding-era understandings,” 8 explaining that the Fourth Amendment “seeks to secure 'the privacies of life' against 'arbitrary power,'” 9 and that “a central aim of the Framers was 'to place obstacles in the way of a too permeating police surveillance.'” 10

Although the sanctity of the home has been strongly reaffirmed, protection of privacy in other contexts becomes more problematic. A two-part test that Justice Harlan suggested in Katz often provides the starting point for analysis.11 The first element, the “subjective expectation” of privacy, has largely dwindled as a viable standard, because, as Justice Harlan noted in a subsequent case, “our expectations, and the risks we assume, are in large part reflections of laws that translate into rules the customs and values of the past and present.” 12 As for the second element, whether one has a “legitimate” expectation of privacy that society finds “reasonable” to recognize, the Court has said that “[l]egitimation of expectations of privacy by law must have 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.” 13

Thus, protection of the home is at the apex of Fourth Amendment coverage because of the right associated with ownership to exclude others;14 but ownership of other things, i.e., automobiles, does not carry a similar high degree of protection.15 That a person has taken normal precautions to maintain his privacy, that is, precautions customarily taken by those seeking to exclude others, is usually a significant factor in determining legitimacy of expectation.16 On the other hand, the Court has held that “a person has no legitimate expectation of privacy in information he voluntarily turns over to third parties.” 17 Some expectations, the Court has held, are simply not among those that society is prepared to accept.18 In the context of norms for the use of rapidly evolving communications devices, the Court was reluctant to consider “the whole concept of privacy expectations” at all, preferring other decisional grounds: “The judiciary risks error by elaborating too fully on the Fourth Amendment implications of emerging technology before its role in society has become clear.” 19

What seems to have emerged is a balancing standard that requires “an assessing of the nature of a particular practice and the likely extent of its impact on the individual’s sense of security balanced against the utility of the conduct as a technique of law enforcement.” Whereas Justice Harlan saw a greater need to restrain police officers through the warrant requirement as the intrusions on individual privacy grow more extensive,20 the Court’s solicitude for law enforcement objectives frequently tilts the balance in the other direction.

Application of this balancing test, because of the Court’s weighing of law enforcement investigative needs,21 and its subjective evaluation of privacy needs, has led to the creation of a two-tier or sliding-tier scale of privacy interests. The privacy test was originally designed to permit a determination that an interest protected by the Fourth Amendment had been invaded.22 If it had been, then ordinarily a warrant was required, subject only to the narrowly defined exceptions, and the scope of the search under those exceptions was “strictly tied to and justified by the circumstances which rendered its initiation permissible.” 23 But the Court now uses the test to determine whether the interest invaded is important or persuasive enough so that a warrant is required to justify it;24 if the individual has a lesser expectation of privacy, then the invasion may be justified, absent a warrant, by the reasonableness of the intrusion.25 Exceptions to the warrant requirement are no longer evaluated solely by the justifications for the exception, e.g., exigent circumstances, and the scope of the search is no longer tied to and limited by the justification for the exception.26 The result has been a considerable expansion, beyond what existed prior to Katz, of the power of police and other authorities to conduct searches.

The Berger and Katz Cases

In Berger v. New York,27 the Court confirmed the obsolescence of the alternative holding in Olmstead that conversations could not be seized in the Fourth Amendment sense.28 Berger held unconstitutional on its face a state eavesdropping statute under which judges were authorized to issue warrants permitting police officers to trespass on private premises to install listening devices. The warrants were to be issued upon a showing of “reasonable ground to believe that evidence of crime may be thus obtained, and particularly describing the person or persons whose communications, conversations or discussions are to be overheard or recorded.” For the five-Justice majority, Justice Clark discerned several constitutional defects in the law. “First, . . . eavesdropping is authorized without requiring belief that any particular offense has been or is being committed; nor that the ‘property’ sought, the conversations, be particularly described.”

“The purpose of the probable-cause requirement of the Fourth Amendment to keep the state out of constitutionally protected areas until it has reason to believe that a specific crime has been or is being committed is thereby wholly aborted. Likewise the statute’s failure to describe with particularity the conversations sought gives the officer a roving commission to ‘seize’ any and all conversations. It is true that the statute requires the naming of ‘the person or persons whose communications, conversations or discussions are to be overheard or recorded. . . .’ But this does no more than identify the person whose constitutionally protected area is to be invaded rather than ‘particularly describing’ the communications, conversations, or discussions to be seized. . . . Secondly, authorization of eavesdropping for a two-month period is the equivalent of a series of intrusions, searches, and seizures pursuant to a single showing of probable cause. Prompt execution is also avoided. During such a long and continuous (24 hours a day) period the conversations of any and all persons coming into the area covered by the device will be seized indiscriminately and without regard to their connection with the crime under investigation. Moreover, the statute permits . . . extensions of the original two-month period – presumably for two months each—on a mere showing that such extension is ‘in the public interest.’. . . Third, the statute places no termination date on the eavesdrop once the conversation sought is seized. . . . Finally, the statute’s procedure, necessarily because its success depends on secrecy, has no requirement for notice as do conventional warrants, nor does it overcome this defect by requiring some showing of special facts. On the contrary, it permits unconsented entry without any showing of exigent circumstances. Such a showing of exigency, in order to avoid notice, would appear more important in eavesdropping, with its inherent dangers, than that required when conventional procedures of search and seizure are utilized. Nor does the statute provide for a return on the warrant thereby leaving full discretion in the officer as to the use of seized conversations of innocent as well as guilty parties. In short, the statute’s blanket grant of permission to eavesdrop is without adequate judicial supervision or protective procedures.” 29

Warden v. Hayden, 387 U.S. 294, 304 (1967). back
Katz v. United States, 389 U.S. 347, 353 (1967) (warrantless use of listening and recording device placed on outside of phone booth violates Fourth Amendment). See also Kyllo v. United States, 533 U.S. 27, 32–33 (2001) (holding presumptively unreasonable the warrantless use of a thermal imaging device to detect activity within a home by measuring heat outside the home, and noting that a contrary holding would permit developments in police technology “to erode the privacy guaranteed by the Fourth Amendment” . back
389 U.S. at 353. Justice Harlan, concurring, formulated a two pronged test for determining whether the privacy interest is paramount: “first that a person have exhibited an actual (subjective) expectation of privacy and, second, that the expectation be one that society is prepared to recognize as ‘reasonable.’” Id. at 361. back
389 U.S. at 351–52. back
Mancusi v. DeForte, 392 U.S. 364, 368 (1968) (official had a reasonable expectation of privacy in an office he shared with others, although he owned neither the premises nor the papers seized). Minnesota v. Olson, 495 U.S. 91 (1990) (overnight guest in home has a reasonable expectation of privacy). But cf. Minnesota v. Carter, 525 U.S. 83 (1998) (a person present in someone else’s apartment for only a few hours for the purpose of bagging cocaine for later sale has no legitimate expectation of privacy); Cf. Rakas v. Illinois, 439 U.S. 128 (1978) (auto passengers demonstrated no legitimate expectation of privacy in glove compartment or under seat of auto). Property rights are still protected by the Amendment, however. A “seizure” of property can occur when there is some meaningful interference with an individual’s possessory interests in that property, and regardless of whether there is any interference with the individual’s privacy interest. Soldal v. Cook County, 506 U.S. 56 (1992) (a seizure occurred when sheriff’s deputies assisted in the disconnection and removal of a mobile home in the course of an eviction from a mobile home park). The reasonableness of a seizure, however, is an additional issue that may still hinge on privacy interests. United States v. Jacobsen, 466 U.S. 109, 120–21 (1984) (DEA agents reasonably seized package for examination after private mail carrier had opened the damaged package for inspection, discovered presence of contraband, and informed agents). back
533 U.S. 27 (2001). back
533 U.S. at 34. back
Carpenter v. United States, 138 S. Ct. 2206, 2214 (2018). back
Id. (quoting Boyd v. United States, 116 U.S. 616, 630 (1886)). back
Id. (quoting United States v. Di Re, 332 U.S. 581, 595 (1948)). back
Justice Harlan’s opinion has been much relied upon. See, e.g., Terry v. Ohio, 392 U.S. 1, 19 (1968); Rakas v. Illinois, 439 U.S. 128, 143–144 n.12 (1978); Smith v. Maryland, 442 U.S. 735, 740–41 (1979); United States v. Salvucci, 448 U.S. 83, 91–92 (1980); Rawlings v. Kentucky, 448 U.S. 98, 105–06 (1980); Bond v. United States, 529 U.S. 334, 338 (2000). back
United States v. White, 401 U.S. 745, 786 (1971). See Smith v. Maryland, 442 U.S. 735, 740 n.5 (1979) (government could not condition “subjective expectations” by, say, announcing that henceforth all homes would be subject to warrantless entry, and thus destroy the “legitimate expectation of privacy” ). back
Rakas v. Illinois, 439 U.S. 128, 144 n.12 (1978). back
E.g., Alderman v. United States, 394 U.S. 165 (1969); Mincey v. Arizona, 437 U.S. 385 (1978); Payton v. New York, 445 U.S. 573 (1980); Kyllo v. United States, 533 U.S. 27, 31 (2001). back
E.g., United States v. Ross, 456 U.S. 798 (1982). See also Donovan v. Dewey, 452 U.S. 594 (1981) (commercial premises); Maryland v. Macon, 472 U.S. 463 (1985) (no legitimate expectation of privacy in denying to undercover officers allegedly obscene materials offered to public in bookstore). back
E.g., United States v. Chadwick, 433 U.S. 1, 11 (1977); Katz v. United States, 389 U.S. 347, 352 (1967). But cf. South Dakota v. Opperman, 428 U.S. 364 (1976) (no legitimate expectation of privacy in automobile left with doors locked and windows rolled up). In Rawlings v. Kentucky, 448 U.S. 98 (1980), the fact that defendant had dumped a cache of drugs into his companion’s purse, having known her for only a few days and knowing others had access to the purse, was taken to establish that he had no legitimate expectation the purse would be free from intrusion. back
Smith v. Maryland, 442 U.S. 735, 74344 (1979). See also United States v. Miller, 425 U.S. 435, 442 (1976). Concurring in United States v. Jones, 565 U.S. 400 (2012), Justice Sotomayor questioned the continuing viability of this principle in “the digital age, in which people reveal a great deal of information about themselves to third parties in the course of carrying out mundane tasks.” Id. at 417 (Sotomayor, J., concurring). Relying on this concurrence, the Carpenter Court recognized a limit to the third-party doctrine when it “decline[d] to extend Smith and Miller” to “the qualitatively different category of cell-site records.” Carpenter, 138 S. Ct. at 2216–17. The Court noted that this data provides “an all-encompassing record of the [cell phone] holder's whereabouts,” tracking “nearly exactly the movements of [the cell phone's] owner” and operating both prospectively and retroactively. Id. at 2217–18. Instead, the Court held that “an individual maintains a legitimate expectation of privacy in the record of his physical movements as captured through” cell-site location information. Id. at 2217. back
E.g., United States v. Miller, 425 U.S. 435 (1976) (bank records); Smith v. Maryland, 442 U.S. 735 (1979) (numbers dialed from one’s telephone); Hudson v. Palmer, 468 U.S. 517 (1984) (prison cell); Illinois v. Andreas, 463 U.S. 765 (1983) (shipping container opened and inspected by customs agents and resealed and delivered to the addressee); California v. Greenwood, 486 U.S. 35 (1988) (garbage in sealed plastic bags left at curb for collection). back
City of Ontario v. Quon, 560 U.S. 746, 759 (2010). The Court cautioned that “[a] broad holding concerning employees' privacy expectations vis-a-vis employer-provided technological equipment might have implications for future cases that cannot be predicted.” Id. at 760. back
United States v. White, 401 U.S. 745, 786–87 (1971) (Justice Harlan dissenting). back
E.g., Robbins v. California, 453 U.S. 420, 429, 433–34 (1981) (Justice Powell concurring), quoted with approval in United States v. Ross, 456 U.S. 798, 815–16 & n.21 (1982). back
Katz v. United States, 389 U.S. 347, 351–52 (1967). back
Terry v. Ohio, 392 U.S. 1, 19 (1968). back
The prime example is the home, so that for entries either to search or to arrest, “the Fourth Amendment has drawn a firm line at the entrance to the house. Absent exigent circumstances, that threshold may not reasonably be crossed without a warrant.” Payton v. New York, 445 U.S. 573, 590 (1980); Steagald v. United States, 451 U.S. 204, 212 (1981); Kirk v. Louisiana, 536 U.S. 635 (2002) (per curiam). See also Mincey v. Arizona, 437 U.S. 385 (1978). Privacy in the home is not limited to intimate matters. “In the home all details are intimate details, because the entire area is held safe fromg prying government eyes.” Kyllo v. United States, 533 U.S. 27, 37 (2001). back
One has a diminished expectation of privacy in automobiles. Arkansas v. Sanders, 442 U.S. 753, 761 (1979) (collecting cases); United States v. Ross, 456 U.S. 798, 804–09 (1982). A person’s expectation of privacy in personal luggage and other closed containers is substantially greater than in an automobile, United States v. Chadwick, 433 U.S. 1, 13 (1977); Arkansas v. Sanders, 442 U.S. 753 (1979), although, if the luggage or container is found in an automobile as to which there exists probable cause to search, the legitimate expectancy diminishes accordingly. United States v. Ross, supra. There is also a diminished expectation of privacy in a mobile home parked in a parking lot and licensed for vehicular travel. California v. Carney, 471 U.S. 386 (1985) (leaving open the question of whether the automobile exception also applies to a “mobile” home being used as a residence and not adapted for immediate vehicular use). back
E.g., Texas v. White, 423 U.S. 67 (1975) (if probable cause to search automobile existed at scene, it can be removed to station and searched without warrant); United States v. Robinson, 414 U.S. 218 (1973) (once an arrest has been validly made, search pursuant thereto is so minimally intrusive in addition that scope of search is not limited by necessity of security of officer); United States v. Edwards, 415 U.S. 800 (1974) (incarcerated suspect; officers need no warrant to take his clothes for test because little additional intrusion). But see Ybarra v. Illinois, 444 U.S. 85 (1979) (officers on premises to execute search warrant of premises may not without more search persons found on premises). back
388 U.S. 41 (1967). back
388 U.S. at 50–53. back
388 U.S. at 58–60. Justice Stewart concurred because he thought that the affidavits in this case had not been sufficient to show probable cause, but he thought the statute constitutional in compliance with the Fourth Amendment. Id. at 68. Justice Black dissented, arguing that the Fourth Amendment was not applicable to electronic eavesdropping but that in any event the “search” authorized by the statute was reasonable. Id. at 70. Justice Harlan dissented, arguing that the statute with its judicial gloss was in compliance with the Fourth Amendment. Id. at 89. Justice White thought both the statute and its application in this case were constitutional. Id. at 107. back

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