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Chimaera II - Your Spying Smartphone: Individual Privacy Is Narrowly Strengthened in Carpenter v. United States, The U.S. Supreme Court’s Most Recent Fourth Amendment Ruling
The University of Florida Levin College of Law Journal of Technology & Policy (2018)
  • Vania Chaker, Esq.

Recently, the United States Supreme Court wrestled with the profoundly complex and bedeviling issue of individual privacy in the landmark case of Carpenter v. United States.[1] It is the most recent in a long line of Fourth Amendment cases that examine an individual’s reasonable expectation of privacy. In Carpenter, the Supreme Court revisited and expanded upon this query from Riley v. California[2] and United States v. Jones[3]—both progeny of Katz v. United States,[4] the leading case in this area of jurisprudence.
The Carpenter Court ruled the government required a warrant before it could use private information arising from defendant Timothy Carpenter’s cellular phone[5]—specifically, his cell site location information (CSLI). In the 5-4 decision, the Court ruled “narrowly” in favor of privacy, finding the government had constitutionally violated Mr. Carpenter’s reasonable expectation of privacy by acquiring this private information without a warrant.[6] It ruled that, as a cell phone customer, Mr. Carpenter could reasonably expect that his CSLI would be treated as private, even though it was in the possession of a third party.[7] In so ruling, the Court declined to apply the long-standing third-party doctrine of United States v. Miller[8]and Smith v. Maryland.[9] These cases, which stand for the proposition that there is a reduced expectation of privacy in information an individual knowingly shares with another, have thus been narrowed.[10]
Against a backdrop of stunningly advanced surveillance technology and the strictures of the United States Constitution, the question of how individual privacy comports with the need for police investigation is a complex and impressively difficult one. In the current political landscape, judicial vigilance becomes increasingly important in protecting the appropriate dimensions of individual privacy. The grave risks of governmental abuse may militate in favor of strengthened judicial oversight in determining the parameters of the state’s broad investigative powers. Strong privacy protections may indeed serve to function as a safeguard against the risks of governmental overreach, police misconduct, and improper warrantless surveillance.

            [1].   Carpenter v. United States, 138 S. Ct. 2206 (2018).
            [2].   Riley v. California, 134 S. Ct. 2473 (2014).
            [3].   United States v. Jones, 132 S. Ct. 945 (2012).
            [4].   Katz v. United States, 389 U.S. 347 (1967).
            [5].   Carpenter, 138 S. Ct. at 2221.
            [6].   Id. at 2219.
            [7].   Id. at 2220.
            [8].   United States v. Miller, 425 U.S. 435 (1976).
            [9].   Smith v. Maryland, 442 U.S. 735 (1979).
         [10].   Carpenter, 138 S. Ct. at 2220.
  • Constitutional law,
  • Third party doctrine,
  • Carpenter v US,
  • Fourth Amendment,
  • Internet of Things,
  • Smartphones,
  • Warrantless Surveillance,
  • Government Surveillance,
  • Privacy Law
Publication Date
September 21, 2018
Citation Information
1 J. Tech. L. & Pol’y – The Forum 1