The Sixth Circuit decision in Carpenter v. United States affirmed the FBI’s warrantless collection of location data that put the defendants’ cell phones within a half-mile to two miles of the location of each of the at issue robberies. Over the course of 127 days, the government collected tens of thousands of location data entries of the suspects’ phones, allowing it to paint a detailed picture of the daily lives and activities of the defendants. This location data was instrumental in placing the defendant’s in a geographic area approximate to the robberies and was part of the evidence that supported their underlying conviction.
The U.S. Supreme Court’s is set to have oral arguments on appeal this fall and its decision will have major implications regarding Law Enforcement’s warrantless collection of cell phone location data from phone carriers. Relying on Fourth Amendment cases that predate the widespread adoption of smart phone technology by the public, the Sixth Circuit ruled that the defendants had “no reasonable expectation of privacy” in their location data because it was being shared with a third party (the phone carriers). This ruling is in line with previous decisions of the U.S. Supreme Court. See e.g. Katz v. United States, 389 U.S. 347 (1967) (to fall within the protection of the Fourth Amendment, an expectation of privacy must satisfy “a twofold requirement”: first, the person asserting it must “have exhibited an actual (subjective) expectation of privacy”; and second, that expectation must “be one that society is prepared to recognize as ‘reasonable.’”).
This “third-party doctrine” has resulted in a significant expansion of Law Enforcement’s ability to conduct searches without the important constitutional checks of a disinterested Judge’s issuance of a warrant review of the reasonableness of the search. There is at least some previous indication by SCOTUS that the court intends to curtail these searches. In 2012, Justice Sotomayor wrote in her concurrence in United States v. Jones "people disclose the phone numbers that they dial or text to their cellular providers; the URLs that they visit and the e-mail addresses with which they correspond to their Internet service providers; and the books, groceries, and medications they purchase to online retailers.... I would not assume that all information voluntarily disclosed to some member of the public for a limited purpose is, for that reason alone, disentitled to Fourth Amendment protection." Jones, 132 S. Ct. 945 (2012).