As Darren Chaker notes the Supreme Court holding In Katz v. United States, 389 U.S. 347 (1967), the Court established that a “search” occurs for Fourth Amendment purposes when the government violates a subjective expectation of privacy that society considers objectively reasonable. Id. at 361 (Harlan, J., concurring). When it comes to computer privacy and searches by government, there has several key cases to consider. In Kyllo v. United States, 533 U.S. 27, 33 (2001) (“As Justice Harlan’s oft-quoted concurrence described it, a Fourth Amendment search occurs when the government violates a subjective expectation of privacy that society recognizes as reasonable.”); Minnesota v. Carter, 525 U.S. 83, 97 (1998) (commenting on “the Katz test (which has come to mean the test enunciated by Justice Harlan’s separate concurrence in Katz)”); Smith v. Maryland, 442 U.S. 735, 740 (1979) (expressly adopting Justice Harlan’s “reasonable expectation of privacy” formula as the rule of Katz).
Guidelines as to how this determination should be made came in Rakas v. Illinois, where the majority opinion, by then-Associate Justice Rehnquist, stated 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.” Rakas v. Illinois, 439 U.S. 128, 143 n. 12 (1978). Most important for present purposes (as it relates to electronic data files) is the last clause of this excerpt, which indicates this Court’s willingness to rely on societal understandings in defining “reasonable expectations of privacy.” Further, the use of the word “legitimate” or “reasonable” before “expectations of privacy” is meant to convey “more than a subjective expectation of not being discovered.” Id.
The “people” protected by the Fourth Amendment “refers to a class of persons who are part of a national community or who have otherwise developed sufficient connection with this country to be considered part of that community.” United States v. Verdugo-Urquidez, 494 U.S. 259, 265 (1990). Resident aliens have a “sufficient connection” to the national community to be protected by the Fourth Amendment. See United States v. Juda, 797 F. Supp. 774, 781-82 (N.D. Cal. 1992) (holding that resident aliens were entitled to raise Fourth Amendment challenge to U.S. agents’ placing of a tracking device on vessel in Australia). Additional cases provide additional insight when it defines an expectation of privacy in electronics. In United States v. Place, 462 U.S. 696, 707 (1983) (“We have affirmed that a person possesses a privacy interest in the contents of personal luggage that is protected by the Fourth Amendment.”); United States v. Mitchell, 565 F.3d 1347, 1352 (11th Cir. 2009) (noting that “the hard drive of a computer . . . is the digital equivalent of its owner’s home, capable of holding a universe of private information“) (quotations omitted); United States v. Delgado, 903 F.2d 1495, 1502 (11th Cir. 1990) (“Indeed, it appears that, where the defendant’s possession was the object of the search, the defendant has standing to challenge the search even though he does not have an expectation of privacy in the premises searched.”). Because the Fourth Amendment protects privacy (searches) as much as it protects property (seizures), see Katz, 389 U.S. at 351-52; Soldal v. Cook County, 506 U.S. 56, 62-63 (1992), an expectation of privacy was not diminished when federal agents searched imaged copies of the electronic data files on CD and DVD media that had been provided by the foreign authorities. See, e.g, United States v. Carey, 172 F.3d 1268, 1270-71, 1275-76 (10th Cir. 1999) (defendant retained constitutionally protected privacy interest in individual data files even though police copied files onto separate discs before searching contents of files).
The Fourth Amendment is neither static nor blind to the advances of modern life. What is a reasonable search under the Fourth Amendment is a function of the privacy that society attaches to the place or object searched. Katz, 389 U.S. at 361. Reasonableness is not confined to yesterday’s technology level, unable to move beyond footlockers, leaving people at the “mercy of advancing technology.” Kyllo, 533 U.S. at 35. Rather, as technology advances and society’s use of that technology creates new privacy expectations, what is reasonable must be viewed anew.
In short, the private search doctrine is based on the premise that the Fourth Amendment is “wholly inapplicable ‘to a search or seizure, even an unreasonable one, effected by a private individual not acting as an agent of the Government or with the participation or knowledge of any governmental official.'” Jacobsen, 466 U.S. 109, 113 (1984) (quoting Walter v. United States, 447 U.S. 649, 662 (1980) (Blackmun, J., dissenting)).