Four models of fourth amendment protection

Stanford Law Review

Volumn 60, Issue 2, 2007, Pages 503-551

  Kerr, Orin S ^a  

^a GEORGE WASHINGTON UNIVERSITY   (United States)

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EID: 38849106262     PISSN: 00389765     EISSN: None     Source Type: Journal    
DOI: None     Document Type: Review

References (251)

1. See Smith v. Maryland, 442 U.S. 735, 740 (1979)
2. (discussing Katz v. United States, 389 U.S. 347, 361 (1967) (Harlan, J., concurring)).
3. See, e.g., O'Connor v. Ortega, 480 U.S. 709, 715 (1987) (O'Connor, J., plurality opinion) ("We have no talisman that determines in all cases those privacy expectations that society is prepared to accept as reasonable.");
4. Oliver v. United States, 466 U.S. 170, 177 (1984) ("No single factor determines whether an individual legitimately may claim under the Fourth Amendment that a place should be free of government intrusion not authorized by warrant.");
5. see also 1 WAYNE R. LAFAVE, SEARCH AND SEIZURE: A TREATISE ON THE FOURTH AMENDMENT § 2.1(a), at 380 (3d ed. 1996) ("The Supreme Court ... has never managed to set out a comprehensive definition of the word 'searches' as it is used in the Fourth Amendment.").
6. Rakas v. Illinois, 439 U.S. 128, 143 n.12 (1978).
7. See, e.g., Warden v. Hayden, 387 U.S. 294 (1967).
8. 389 U.S. at 360 (Harlan, J., concurring).
9. Richard G. Wilkins, Defining the "Reasonable Expectation of Privacy": An Emerging Tripartite Analysis, 40 VAND. L. REV. 1077, 1107 (1987).
10. Sherry F. Colb, What Is a Search? Two Conceptual Flaws in Fourth Amendment Doctrine and Some Hints of a Remedy, 55 STAN. L. REV. 119, 122 (2002).
11. Silas J. Wasserstrom & Louis Michael Seidman, The Fourth Amendment as Constitutional Theory, 11 GEO. L.J. 19, 29 (1988).
12. See, e.g., CHARLES H. WHITEBREAD & CHISTOPHER SLOBOGIN, CRIMINAL PROCEDURE: AN ANALYSIS OF CASES AND CONCEPTS (3d ed. 1993).
13. See, e.g., ROBERT M. BLOOM, SEARCHES, SEIZURES, AND WARRANTS 46 (2003) ("How do we know what society is prepared to accept as reasonable? Because there is no straightforward answer to this question, 'reasonable' has largely come to mean what a majority of the Supreme Court Justices says is reasonable . . . .");
14. PHILIP E. JOHNSON, CASES AND MATERIALS ON CRIMINAL PROCEDURE 19 (3d ed. 2000) ("When the court refers to society's judgment, it is looking in a mirror."). Wayne LaFave's influential treatise suggests that the best explanation for current doctrine is a tautology-"the fourth amendment protects those interests that may justifiably claim fourth amendment protection"-with the important caveat that most Supreme Court Justices do not understand what justifiably claims Fourth Amendment protection.
15. LAFAVE, supra note 2, § 2.1(d), at 393
16. (quoting Anthony G. Amsterdam, Perspectives on the Fourth Amendment, 58 Minn. L. Rev. 349, 385 (1974)).
17. See, e.g., Donald R.C. Pongrace, Stereotypification of the Fourth Amendment's Public/Private Distinction: An Opportunity for Clarity, 34 AM. U. L. REV. 1191, 1208 (1985) ("[M]ost commentators have recognized that regardless of the political palatability of recent decisions, fourth amendment doctrine is in a state of theoretical chaos that belies its supposed objective legitimation of governmental intrusions into our 'private affairs.'").
18. See, e.g., United States v. Carroll Towing Co., 159 F.2d 169 (2d Cir. 1947).
19. See, e.g., MODEL PENAL CODE § 2.02(c) (1985).
20. See infra Part I.
21. See Illinois v. Rodriguez, 497 U.S. 177, 185 (1990).
22. This analysis assumes that the government conduct is not a seizure. Seizures are regulated by the Fourth Amendment even if they do not violate a reasonable expectation of privacy. See Soldal v. Cook County, 506 U.S. 56 (1992).
23. Cf. PHILIP BOBBITT, CONSTITUTIONAL FATE: THEORY OF THE CONSTITUTION (1982). For reasons that will become clear later in the Article, I will exclude stare decisis as an independent rationale for or against Fourth Amendment protection. Precedent is often used as a crutch in Fourth Amendment law; the Supreme Court will often say that the reasonable expectation of privacy test just so happens to match pve-Katz interpretations of the Fourth Amendment.
24. See, for example, United States v. White, 401 U.S. 745, 750 (1971),
25. reaffirmed by On Lee v. United States, 343 U.S. 747 (1952),
26. which had held that the police did not need a warrant to go undercover and wear a "wire" that transmitted the defendant's conversations to a police observation post, and Oliver v. United States, 466 U.S. 170 (1984),
27. reaffirmed by Hester v. United States, 265 U.S. 57 (1924), retaining the "open fields" doctrine.
28. See infra Part I.E.
29. In part, this is the "understandings that are recognized and permitted by society," discussed in Rakas v. Illinois, 439 U.S. 128, 143 n.12 (1978).
30. This appears to be the version of the reasonable expectation of privacy test that is commonly used in the privacy torts. See, e.g., Lior Jacob Strahilevitz, A Social Networks Theory of Privacy, 72 U. CHI. L. REV. 919 (2005). This test is also used in the professional responsibility context to determine when the attorney-client privilege is retained.
31. See, e.g., ABA Comm. on Ethics and Prof 1 Responsibility, Formal Op. 99-413 (1999) (concluding that e-mail supports a reasonable expectation of privacy because e-mail is likely to remain private).
32. 529 U.S. 334 (2000).
33. Id. at 336.
34. Id. at 337.
35. Id. at 338-39.
36. 495 U.S. 91 (1990).
37. Id. at 98.
38. Id.
39. Id. at 99.
40. 476 U.S. 207 (1986).
41. Id. at 215. There are other explanations in the Ciraolo majority opinion; this is only one among several.
42. Id. at 223 (Powell, J., dissenting) ("[T]he actual risk to privacy from commercial or pleasure aircraft is virtually nonexistent. Travelers on commercial flights, as well as private planes used for business or personal reasons, normally obtain at most a fleeting, anonymous, and nondiscriminating glimpse of the landscape and buildings over which they pass.").
43. For other examples, see O'Connor v. Ortega, 480 U.S. 709 (1987) (O'Connor, J., plurality opinion) (addressing government workplace privacy);
44. California v. Carney, 471 U.S. 386 (1985) (concluding that a person has a lesser expectation of privacy in a car because cars are heavily regulated and therefore drivers and passengers do not expect as much privacy in them as they do in homes);
45. and United States v. Dionisio, 410 U.S. 1 (1973) (addressing grand jury subpoena).
46. United States v. Carroll Towing Co., 159 F.2d 169, 173 (2d Cir. 1947).
47. From this perspective, the reasonable expectation of privacy test is a bit circular: whether a reasonable person would expect privacy arguably depends at least in part on the Supreme Court's cases construing the Fourth Amendment. See, e.g., JEFFREY ROSEN, THE UNWANTED GAZE: THE DESTRUCTION OF PRIVACY IN AMERICA 60 (2000) ("Harlan's test was applauded as a victory for privacy, but it soon became clear that it was entirely circular.");
48. Michael Abramowicz, Constitutional Circularity, 49 UCLA L. REV. 1, 60-61 (2001) ("Fourth Amendment doctrine, moreover, is circular, for someone can have a reasonable expectation of privacy in an area if and only if the Court has held that a search in that area would be unreasonable."). Of course, even under this approach, the circularity is modest. Only a lawyer would think that a person's chances of having privacy in a particular place hinges in large part on whether the police can enter it legally without a warrant, consent, or exigent circumstances. Fortunately, police searches are rarer than that whether or not a warrant is required.
49. 543 U.S. 405 (2005).
50. Id. at 408-09
51. (quoting United States v. Jacobsen, 466 U.S. 109, 122 (1984)).
52. Jacobsen, 466 U.S. at 122.
53. Hoffa v. United States, 385 U.S. 293 (1966).
54. United States v. White, 401 U.S. 745 (1971).
55. United States v. Miller, 425 U.S. 435 (1976).
56. Id. at 443.
57. See, e.g., Smith v. Maryland, 442 U.S. 735, 745 (1979) ("We are not inclined to make a crazy quilt of the Fourth Amendment, especially in circumstances where (as here) the pattern of protection would be dictated by billing practices of a private corporation.");
58. see also Anderson v. Pollard, 2006 U.S. Dist. LEXIS 81960, at *11-12 (E.D. Wis. Nov. 7, 2006) (arguing unsuccessfully that a prison cell retained a reasonable expectation of privacy because it was not searched very often).
59. 456 U.S. 798 (1982).
60. Id. at 822 (footnote omitted).
61. 466 U.S. 109 (1984).
62. Id. at 122.
63. Id. at 123.
64. Id.
65. Id.
66. Id.
67. 476 U.S. 227 (1986).
68. Id. at 238.
69. 468 U.S. 705 (1984).
70. Id. at 715.
71. See Daniel J. Solove, A Taxonomy of Privacy, 154 U. PA. L. REV. 477 (2006).
72. See, e.g., Rakas v. Illinois, 439 U.S. 128, 143 n.12 (1978).
73. Christopher Slobogin and Joseph Schumacher emphasized this point in a 1993 article that tested the social expectations of 217 individuals (most of them students). Christopher Slobogin & Joseph E. Schumacher, Reasonable Expectations of Privacy and Autonomy in Fourth Amendment Cases: An Empirical Look at "Understandings Recognized and Permitted by Society, " 42 DUKE L.J. 727 (1993). The subjects of the study were asked to rank the "intrusiveness" of various law enforcement practices featured in Fourth Amendment decisions. Slobogin and Schumacher found little correlation between the scope of Fourth Amendment protection and the intrusiveness of different steps: "[T]he Supreme Court's conclusions about the scope of the Fourth Amendment are often not in tune with commonly held attitudes about police investigative techniques."
74. Id. at 774.
75. 480 U.S. 321 (1987).
76. Id. at 325.
77. See United States v. Jacobsen, 466 U.S. 109, 120 n.17 (1984).
78. See id. ("A container which can support a reasonable expectation of privacy may not be searched, even on probable cause, without a warrant.").
79. See supra notes 38-44.
80. See Entick v. Carrington, 19 Howell's State Trials 1029, 1030 (CP. 1765).
81. See Orin S. Kerr, The Fourth Amendment and New Technologies: Constitutional Myths and the Case for Caution, 102 MICH. L. REV. 801, 809-15 (2004).
82. Soldal v. Cook County, 506 U.S. 56, 64 (1992).
83. See Kerr, supra note 64.
84. 439 U.S. 128 (1978).
85. Id. at 143 n.12 (internal citations omitted).
86. Id. at 129.
87. 488 U.S. 445 (1989).
88. Id. at 451 (White, J., plurality opinion, joined by Rehnquist, C.J., Scalia, J., and Kennedy, J.).
89. Dow Chemical Co. v. United States, 476 U.S. 227 (1986).
90. Id. at 249 (Powell, J., concurring in part, dissenting in part).
91. Perhaps the most remarkable example of this is the discussion of Bahamian bank secrecy law in United States v. Payner, 447 U.S. 727 (1980). Payner argued that Bahamian bank secrecy laws created a reasonable expectation of privacy in his bank records in the Bahamas. The Court disagreed, finding that "[t]he statute is hardly a blanket guarantee of privacy. Its application is limited; it is hedged with exceptions; and we have been directed to no authority construing its terms."
92. Id. at 732 n.4.
93. Another example is Alderman v. United States, 394 U.S. 165 (1969), in which the Court held that wiretapping a home telephone line implicates the homeowner's reasonable expectation of privacy even if he was not a party to the call intercepted. According to the Court, the homeowner has Fourth Amendment rights even if his own privacy rights are not invaded: the fact that the surveillance occurs inside the owner's home is enough to confer Fourth Amendment protection.
94. Id. at 179-80 ("The rights of the owner of the premises are as clearly invaded when the police enter and install a listening device in his house as they are when the entry is made to undertake a warrantless search for tangible property . . . .").
95. 466 U.S. 170 (1984).
96. This doctrine was first established in Hester v. United States, 265 U.S. 57, 59 (1924)
97. (citing WILLIAM BLACKSTONE, 4 COMMENTARIES *223, *225-226).
98. If the police get too close to the home they will cross on to the "curtilage," which is the area near the home that is essentially home-like and thus protected by the Fourth Amendment. See United States v. Dunn, 480 U.S. 294 (1987).
99. Oliver, 466 U.S. at 183-84. It is possible to reconcile these outcomes: trade secrets are about secrets, whereas trespass law is not. So it could be consistent with a theory that some types of positive law should be recognized under the positive law model while others types should not be. Courts haven't drawn these lines, though, in part because trespass law often is about privacy.
100. 486 U.S. 35 (1988).
101. Id. at 43.
102. Id. at 43
103. (quoting Oliver, 466 U.S. at 178 (emphasis added in Greenwood)).
104. See Amsterdam, supra note 10, at 403;
105. see also Colb, supra note 7, at 124 (arguing that the reasonable expectation of privacy test forces "[decisions . . . [to] rest on normative choices").
106. See infra Part II.
107. 389 U.S. 347 (1967).
108. Id. at 352.
109. 533 U.S. 27 (2001).
110. Id. at 40.
111. Id. at 34.
112. Id.
113. (quoting Silverman v. United States, 365 U.S. 505 (1961)).
114. Id.
115. The Court invoked a similar normative judgment in United States v. Karo, 468 U.S. 705 (1984), the case involving use of an electronic locating device. According to the majority, using a locating device was a "search" because the unregulated use of such devices would be too dangerous: "Indiscriminate monitoring of property that has been withdrawn from public view would present far too serious a threat to privacy interests in the home to escape entirely some sort of Fourth Amendment oversight."
116. Id. at 716.
117. 442 U.S. 735 (1979).
118. Id. at 736 & n. 1, 737.
119. Id. at 750-51 (Marshall, J., dissenting).
120. See id. at 751.
121. 468 U.S. 517 (1984).
122. Id. at 521.
123. Id.
124. Id. at 526.
125. See, e.g., Delaware v. Prouse, 440 U.S. 648, 662-63 (1979) (justifying the conclusion that searching a car violates a reasonable expectation of privacy on the ground that "[w]ere the individual subject to unfettered governmental intrusion every time he entered an automobile, the security guaranteed by the Fourth Amendment would be seriously circumscribed");
126. United States v. White, 401 U.S. 745, 778 (1971) (Harlan, J., dissenting) (arguing that the reasonable expectation of privacy framework should be decided in light of policy considerations).
127. This focus on policy interests in Fourth Amendment law arguably goes back to the first Fourth Amendment decision, Boyd v. United States, 116 U.S. 616 (1886). The Court's description of the Fourth Amendment's purpose in that case is notable for its potpourri of themes: according to Justice Bradley, the "essence" of the Fourth Amendment was protection against "the invasion of [a person's] indefeasible right of personal security, personal liberty, and private property."
128. Id. at 630.
129. Following Boyd, the Court's focus on weighing of privacy interests was a common theme in early cases. In 1932, for example, the Court warned in United States v. Lefkowitz, that the Fourth Amendment must be "construed liberally to safeguard the right of privacy." 285 U.S. 452, 464 (1932).
130. And in Wolf v. Colorado, Justice Frankfurter urged that at the "core" of the Fourth Amendment was "[t]he security of one's privacy against arbitrary intrusion by the police." 338 U.S. 25, 27 (1949).
131. See, e.g., United States v. Jeffers, 342 U.S. 48 (1951);
132. see also McGuire v. United States, 273 U.S. 95 (1927).
133. A few cases suggest that the policy concerns should go beyond a mere balancing of interests to include pragmatic questions such as institutional competence, see Kyllo v. United States, 533 U.S. 27, 51 (2001) (Stevens, J. dissenting), and the administrability of rules,
134. see Smith v. Maryland, 442 U.S. 735, 744-45 (1979).
135. See, e.g., California v. Ciraolo, 476 U.S. 207 (1986). Ciraolo involved aerial surveillance of marijuana plants growing in the defendant's backyard, and the opinion relied on the probabilistic and positive law models but ignored the policy model. According to Chief Justice Burger, aerial surveillance from public airspace does not violate a reasonable expectation of privacy because any member of the public could legally conduct such surveillance (positive law), and in an age of routine air travel expecting privacy is unreasonable (probabilistic).
136. See id. at 213-14. But the opinion never explores the policy consequences of its holding, never balances the privacy and law enforcement interests, and never suggests that such inquiries might be relevant. Although we can imagine such arguments, none appear in the opinion.
137. Justice Scalia's opinion for the Court in Kyllo, 533 U.S. at 29, is a good example. Although it relies heavily on the policy model, it also discusses and attempts to conform to both the private facts model and the probabilistic model. The government's brief relied heavily on the private facts model, and claimed that merely obtaining the temperature of the home was not sufficiently "intimate" to constitute a search. Justice Scalia disagreed, contending that the temperature of the home was "intimate" because all facts about the inside of the home are "intimate" facts.
138. Id. at 37. Scalia also defined the scope of the Court's holding using the probabilistic model: the prohibition against the warrantless use of sense-enhancing devices applied only to those devices "not in general public use."
139. Id. at 34. Use of the thermal imaging device was a search because "thermal imaging is not 'routine'" under the probabilistic model.
140. Id. at 39 n.6. If using such devices had been routine, the Court suggested, the outcome might very well be different.
141. See supra notes 19 and 82 and accompanying text.
142. Cf. Amsterdam, supra note 10, at 367 (distinguishing between "atomistic" and "regulatory" approaches to the Fourth Amendment).
143. For example, imagine a police officer breaks into a post office and rifles through the mail of a suspect he is investigating; when he finds a private letter, the officer opens the letter and reads it. A micro-scale inquiry might look at whether the officer violated any laws, or what information he obtained in that particular case. A macro-scale inquiry might see the case as one example of government access to postal letters, and seek to base a rule on the general and typical characteristics of postal mail and postal mail privacy.
144. Hudson v. Palmer, 468 U.S. 517 (1984).
145. Kyllo, 533 U.S. 27.
146. Katz v. United States, 389 U.S. 347 (1967).
147. Consider whether a person has a reasonable expectation of privacy in her postal mail letters. Under the probabilistic model, the question is whether, taking into account all of the possible ways that mail privacy might be violated, discounted by their probability, a person could reasonably expect privacy in her postal mail. This is a macro-scale inquiry, in that it concerns the general question of the odds of an invasion of mail privacy rather than an estimate of the chances that the exact invasion that did occur was likely to occur. The chances that the exact invasion that did occur was likely to occur ex ante is irrelevant under the probabilistic model. For example, if an FBI agent breaks into a post office and opens a letter addressed to a suspect, the probabilistic model would not focus attention on the likelihood that the FBI agent would break in exactly as he did, but on the likelihood of the letter being opened by the government in a range of hypothetical scenarios.
148. See Katz, 389 U.S. at 373-74 (Black, J., dissenting) (noting that the Supreme Court was interpreting the Fourth Amendment less as a restriction on unreasonable searches and seizures and more as a general mechanism for limiting police investigations). I should add a caveat here: the Fourth Amendment covers evidence collection other than the statements of individual people. That area is addressed by the Fifth Amendment.
149. Brigham City v. Stuart, 126 S. Ct. 1943, 1947 (2006) ("[T]he ultimate touchstone of the Fourth Amendment is 'reasonableness' . . . ."
150. (quoting Flippo v. West Virginia, 528 U.S. 11, 13 (1999) (per curiam)));
151. United States v. Knights, 534 U.S. 112, 118 (2001) ("The touchstone of the Fourth Amendment is reasonableness . .. .").
152. See Knights, 534 U.S. at 118-19 ("The touchstone of the Fourth Amendment is reasonableness, and the reasonableness of a search is determined '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.'" (quoting Wyoming v. Houghton, 526 U.S. 295, 300 (1999))).
153. See Wong Sun v. United States, 371 U.S. 471, 485 (1963).
154. Cf. Gerald G. Ashdown, Good Faith, the Exclusionary Remedy, and Rule-Oriented Adjudication in the Criminal Process, 24 WM. & MARY L. REV. 335, 336-37 (1983) ("Although the case-by-case approach may retain needed flexibility, its amorphous nature provides little guidance to the police as to what investigatory practices will be viewed retrospectively as reasonable on balance with the individual interest affected.").
155. Further, every defendant can file a motion to suppress on federal Fourth Amendment grounds, and most defendants have a very strong incentive to file claims even if they border on frivolous. Although most claims will fail, defendants do not pay the cost of filing the motion; defendants facing jail time are provided with attorneys free of charge under the Sixth Amendment. See generally Gideon v. Wainwright, 372 U.S. 335 (1963).
156. See generally Wayne R. LaFave, "Case-By-Case Adjudication" Versus "StandardizedProcedures": The Robinson Dilemma, 1974 SUP. CT. REV. 127.
157. 453 U.S. 454, 458 (1981)
158. (quoting LaFave, supra note 117, at 141).
159. Id.
160. (quoting LaFave, supra note 117, at 142). Clear rules will not be possible in every case, of course. For example, they are not feasible in contexts involving emergencies, such as those that implicate the exigent circumstances exception. However, rules are preferable to standards where feasible.
161. See, e.g., Flippo v. West Virginia, 528 U.S. 11, 13-14 (1999) (per curiam) ("A warrantless search by the police is invalid unless it falls within one of the narrow and well-delineated exceptions to the warrant requirement. . . .").
162. U.S. CONST, amend. IV.
163. See Amsterdam, supra note 10, at 414-15.
164. I am excluding Fourth Amendment "seizures" here, which are covered by separate rules.
165. This function is sometimes obscured by Fourth Amendment doctrine, which of course labels the question as whether the conduct is a "search" at all. This bifurcation allows the courts to carve out police conduct from reasonableness review. From a practical perspective, however, it is easier to understand the difference as being whether the police conduct is reasonable per se or needs to be assessed for reasonableness based on the circumstances.
166. See generally FREDERICK SCHAUER, PLAYING BY THE RULES: A P HILOSOPHICAL EXAMINATION OF RULE-BASED DECISION-MAKING IN LAW AND IN LIFE (1991); Louis Kaplow, Rules Versus Standards: An Economic Analysis, 42 DUKE L.J. 557 (1992);
167. Cass R. Sunstein, Problems with Rules, 83 CAL. L. REV. 953 (1995).
168. 468 U.S. 517 (1984).
169. 466 U.S. 109 (1984).
170. 476 U.S. 207 (1986).
171. See United States v. Dunn, 480 U.S. 294 (1987).
172. See, e.g., United States v. Seckman, 175 F. App'x 193, 196 (10th Cir. 2006) (noting that under the four-factor open fields doctrine, the police can go "places where visitors could be expected to go, i.e. walkways, driveways or porches").
173. See 1 WAYNE R. LAFAVE, SEARCH AND SEIZURE: A TREATISE ON THE FOURTH AMENDMENT 321-780 (4th ed. 2004).
174. See United States v. Caymen, 404 F.3d 1196 (9th Cir. 2005) (finding no reasonable expectation of privacy in the contents of a stolen computer).
175. United States v. Arellano-Ochoa, 461 F.3d 1142 (9th Cir. 2006). The opinion begins, "We publish to clarify Fourth Amendment law regarding the police opening a screen door without a search warrant."
176. Id. at 1143. Relying on the probabilistic model, the court ruled that the answer hinges on whether the solid door behind the screen door is open or closed. Opening a screen door backed by a closed solid door does not violate a reasonable expectation of privacy, whereas opening a screen door violates a reasonable expectation of privacy if the solid door happens to be open.
177. Id. at 1145.
178. See, e.g., United States v. Dorais, 241 F.3d 1124, 1128 (9th Cir. 2001) ("[A] defendant has no reasonable expectation of privacy in a hotel room when the rental period has expired and the hotel has taken affirmative steps to repossess the room.");
179. United States v. Nerber, 222 F.3d 597, 600 n.2 (9th Cir. 2000) ("For Fourth Amendment purposes, a hotel room is treated essentially the same, if not exactly the same, as a home.").
180. United States v. Thomas, 447 F.3d 1191, 1196-99 (9th Cir. 2006).
181. See, e.g., United States v. David, 756 F. Supp. 1385 (D. Nev. 1991).
182. See Amezquita v. Hernandez-Colon, 518 F.2d 8 (1st Cir. 1975) (finding no reasonable expectation of privacy for squatters).
183. United States v. Barajas-Avalos, 377 F.3d 1040 (9th Cir. 2004) (holding that approaching a window of a home and peering inside is a search).
184. Cf. Amsterdam, supra note 10, at 384.
185. Cf. Rakas v. Illinois, 439 U.S. 128, 143 n.12 (1978) (noting that a burglar who has entered a home to commit a crime cannot have a reasonable expectation of privacy there).
186. Cf. HENRY M. HART, JR. & ALBERT M. SACKS, THE LEGAL PROCESS 148 (1994) ("Law is a doing of something, a purposive activity, a continuous striving to solve the basic problems of social living . . . . Legal arrangements (laws) are provisions for the future in aid of this effort.").
187. 488 U.S. 445 (1989).
188. See RICHARD A. POSNER, THE ECONOMICS OF JUSTICE 314 n.8 (1981) (noting that under the open fields doctrine, the Fourth Amendment permits invasions of property without triggering Fourth Amendment protection because the property invasion does not trigger a privacy invasion).
189. See Kerr, supra note 64, at 864-67.
190. Cf. Olmstead v. United States, 277 U.S. 438, 479 (1928) (Brandeis, J., dissenting).
191. In Kyllo, Justice Scalia tried to reconcile this by saying that any information about the inside of the home is automatically private. 533 U.S. 27, 34 (2001).
192. But this is surely overbroad, as cases like Smith v. Maryland, 442 U.S. 735 (1979) (holding that pen register information sent from a home is not covered by Fourth Amendment), would suggest.
193. 543 U.S. 405 (2005).
194. This problem doesn't arise with dog sniffs because a well-trained dog either finds nothing or alerts to the presence of narcotics. Those are the only options, and neither option involves the possible disclosure of private facts.
195. See supra Part H.A.
196. Professor Amsterdam believed courts could and perhaps should do so. See Amsterdam, supra note 10. Professor Amsterdam concluded that courts could not be honest that policy concerns were driving the scope of the Fourth Amendment because police officers could not implement such policy concerns in the field.
197. See id. at 403-05. This explanation is weak, however, because the rationale for a court's decision is distinct from its resulting rule. That is, courts could easily apply the policy model and then announce a rule; the officers would then follow the rule and could safely ignore the policy argument that led to it. The difficulty with exclusive reliance on the policy model has a different source.
198. For the distinction between a "top down" and "bottom up" regulatory system, see generally Richard A. Posner, Legal Reasoning from the Top Down and from the Bottom Up: The Question of Unenumerated Constitutional Rights, 59 U. CHI. L. REV. 433 (1992).
199. As Judge Posner explains: In top-down reasoning, the judge or other legal analyst invents or adopts a theory about an area of law-perhaps about all law-and uses it to organize, criticize, accept or reject, explain or explain away, distinguish or amplify the existing decisions to make them conform to the theory and generate an outcome in each new case as it arises that will be consistent with the theory and with the canonical cases, that is, the cases accepted as authoritative within the theory. ... In bottom-up reasoning, which encompasses such familiar lawyers' techniques as "plain meaning" and "reasoning by analogy," one starts with the words of a statute or other enactment, or with a case or a mass of cases, and moves from there-but doesn't move far .... Id. at 433.
200. See also Ronald J. Allen & Ross M. Rosenberg, The Fourth Amendment and the Limits of Theory: Local Versus General Theoretical Knowledge, 72 ST. JOHN'S L. REV. 1149 (1998).
201. See Amsterdam, supra note 10, at 386-87 ("[T]he police engage in a vast range of activities affecting a broad spectrum of citizens' interests in a complex variety of ways.").
202. According to the U.S. Census Bureau, in 2006 there were 5.1 million state government employees, see State Government Employment Data: March 2006, http://ftp2.census.gov/govs/apes/06stus.txt, and 2.7 million federal government employees,
203. see Federal Government Civilian Employment by Function: December 2006, http://ftp2.census.gov/govs/apes/06fedfun.pdf.
204. Bureau of Justice Stats., U.S. Dep't of Justice, Law Enforcement Statistics, http://www.ojp.usdoj.gov/bjs/lawenf.htm
205. According to FBI figures, there were about fourteen million arrests in the United States in 2006. FED. BUREAU OF I NVESTIGATION, CRIME IN THE UNITED STATES tbl.29 (2006), available at http://www.fbi.gov/ucr/cius2006/data/ table_29.html.
206. Further, heavy reliance on treatises such as Wayne R. LaFave's Search and Seizure, supra note 131, means that as soon as a rule is settled enough to appear in LaFave's treatise, many courts will simply treat it as "the law."
207. Cf. Paul M. Bator, What Is Wrong with the Supreme Court?, 51 U. PITT. L. REV. 673, 678 (1990) ("And what is the capacity of the Supreme Court? Like it or not, it is finite. Over the years, we have learned that the United States Supreme Court cannot be asked to decide more than 150 to 175-200 at the most-cases with full opinion in a year.").
208. See generally Philip Allen Lacovara, The Incredible Shrinking Court, AM. LAW., Dec. 2003, at 53, 54.
209. A Westlaw search for the phrase "reasonable expectation of privacy" in the SCT database yields 81 hits as of March 1, 2007. About half of these cases are decisions that actually apply the test as compared to those that simply mention the phrase in the course of discussing another topic.
210. 543 U.S. 405 (2005).
211. 533 U.S. 27 (2001).
212. See H.W. PERRY, JR., DECIDING TO DECIDE: AGENDA SETTING IN THE UNITED STATES SUPREME COURT 246, 251 (1991). The Supreme Court agreed to hear only about one percent of the cases it is petitioned to review. By far the most important factor in whether the Supreme Court agreed to take a case is whether the lower courts have divided on how the law applies to that set of facts.
213. Absent a lower court division, the chance that the Supreme Court would agree to hear a case to resolve whether a police practice violated a reasonable expectation of privacy is extremely low.
214. If a split exists in foreign jurisdictions, the officer will not have any assurance that a court would rule in the government's favor.
215. This is limited by the possibility that the court's rule will trample on other holdings, however.
216. See generally ORIN S. KERR, COMPUTER CRIME LAW 394-445 (2006).
217. Consider the precision of Justice Scalia's rule in the thermal imaging case, Kyllo v. United States, 533 U.S. 27 (2001). Scalia's rule announces that the police violate a reasonable expectation of privacy when they use (a) sense-enhancing devices, (b) not in general public use, (c) to obtain details of the home not otherwise available without physical penetration of the home.
218. See id. at 34. This is a carefully articulated rule, reflecting a carefully chosen category under the policy model.
219. 468 U.S. 517 (1984).
220. 533 U.S. 27.
221. In an important article, Ronald Allen and Ross Rosenberg have argued that Fourth Amendment law consists of "localized knowledge," individual rules that are very clear in context but that lack a single top-down theory. See Allen & Rosenberg, supra note 151.1 agree in part. Like Allen and Rosenberg, I see the development of Fourth Amendment law as largely a bottom-up rather than top-down process. I also agree that localized rules are a critical feature of Fourth Amendment doctrine. My approach differs in two essential ways, however. First, unlike Allen and Rosenberg, I do see a unifying goal that drives judges and Justices in Fourth Amendment cases. Allen and Rosenberg envision Fourth Amendment rules as organic, as the products of a grown system rather than a made one.
222. See id. at 1198-99. In contrast, I think the system is made, but simply in a piece-by-piece way; it is made to create reasonable police practices in a system of exclusionary remedies. Second, I use the phrase "bottom-up" somewhat differently than do Allen and Rosenberg. Allen and Rosenberg focus, like most commentators, on the Supreme Court. In contrast, I mean "bottom-up" to refer literally to cases coming from the decentralized lower courts.
223. 466 U.S. 109 (1984).
224. 476 U.S. 227 (1986).
225. 468 U.S. 705 (1984).
226. 460 U.S. 276 (1983).
227. In contrast, the Court has rejected the private facts approach in cases involving the physical moving and opening of physical things such as packages. See supra notes 58-59 and accompanying text (discussing Arizona v. Hicks, 480 U.S. 321 (1987)).
228. 529 U.S. 334 (2000).
229. 495 U.S. 91 (1990).
230. See, e.g., Rakas v. Illinois, 439 U.S. 128 (1978) (applying positive law model to search of an automobile).
231. Once again, the trend has exceptions. Most notably, the open fields doctrine permits a great deal of trespass on private property, justified under the private facts model instead of the positive law model. See Oliver v. United States, 466 U.S. 170 (1984) (arguing that walking on open fields did not violate a reasonable expectation of privacy because open fields were not likely to be places in which the police would uncover private facts). It's actually somewhat unclear whether this rationale counts as the private facts model or the policy model: it uses the language of the private facts model, but at a macro scale it seems most at home in the policy model.
232. 468 U.S. 517 (1984).
233. Id. at 526.
234. 533 U.S. 27 (2001).
235. The first recorded decision on the Fourth Amendment implications of a thermal imaging device appears to be United States v. Penny-Feeney, 773 F. Supp. 220 (D. Haw. 1991), which involved use of a thermal imaging device in April 1990.
236. 486 U.S. 35 (1988);
237. see, e.g., United States v. Myers, 46 F.3d 668 (7th Cir. 1995);
238. State v. Siegal, 934 P.2d 176 (Mont. 1997).
239. See, e.g., Myers, 46 F.3d 668.
240. 476 U.S. 227 (1986).
241. 460 U.S. 276 (1983).
242. 468 U.S. 705 (1984).
243. See United States v. Robinson, 62 F.3d 1325 (11th Cir. 1995) (upholding warrantless use of a thermal imager); United States v. Ishmael, 48 F.3d 850 (5th Cir. 1995);
244. Myers, 46 F.3d 668;
245. United States v. Pinson, 24 F.3d 1056 (8th Cir. 1994).
246. See, e.g., Commonwealth v. Gindlesperger, 743 A.2d 898, 906 (Pa. 1999) ("[W]e conclude that Appellee met the requirements of Katz and thus established that a search implicating the Fourth Amendment occurred when law enforcement agents scanned his home with the WASP device.").
247. United States v. Kyllo, 533 U.S. 27 (2001).
248. See, e.g., United States v. Runyan, 275 F.3d 449, 457 (5th Cir. 2001) ("[W]hether an interest is protected by the Fourth Amendment depends on five factors: (1) whether the defendant has a [property or] possessory interest in the thing seized or the place searched, (2) whether he has the right to exclude others from that place, (3) whether he has exhibited a subjective expectation of privacy that it would remain free from governmental intrusion, (4) whether he took normal precautions to maintain privacy, and (5) whether he was legitimately on the premises." (internal quotations omitted)).
249. See id.;
250. see also Kee v. City of Rowlett, 247 F.3d 206, 213 (5th Cir. 2001).
251. Kerr, supra note 64, at 816.