Court: police use of cellphone location data generally requires warrant

In Friday’s Carpenter v. United States the Supreme Court by 5-4, with Chief Justice John Roberts writing and joined by the four liberals, held that police collection of cellphone location records covering a period of a week is a search covered by the Fourth Amendment and generally requires a warrant. Orin Kerr has first thoughts. Ilya Shapiro at Cato writes that the Court reaches “the right result for the wrong reason,” in an “artificial muddle” of a decision that carves an exception into the third-party doctrine without the more searching rethinking of search and seizure law that is needed.

More promising, Shapiro says, is Justice Neil Gorsuch’s opinion — which he styles as a dissent, but is a concurrence in all but name — which points the way to rethinking and strengthening Fourth Amendment search and seizure law along first principles of “the people’s right to be secure in their ‘persons, houses, papers, and effects’ based not on privacy expectations but on property rights, contract law, and statutory protections (all of which can certainly be applied in the modern digital age).” The alternative, says Shapiro, will be for the Court to fall back on “reinventing the Fourth Amendment with each technological revolution,” amid new ad hoc exceptions and elaborations. More background at Cato at earlier stages of the case: Matthew Feeney on oral argument, merits brief, certiorari brief.


  • Since the 4th covers searches and seizures, how come cash and other transportable property gets seized without warrant, trial or even charges being pressed against anything other than the property itself? They act like with civil forfeiture that the property doesn’t have an owner… Gotta love that war on drugs. And terrorism… And generally anything which has turned law enforcement into the old fashioned bandit gang out for profit regardless of law and morality.

    Gosh, seems kinda harsh considering I’ve never had as much as a stick of gum taken… But seriously, who can say that it actually complies with the 4th? What about innocent until proven guilty?

    • With civil asset forfeiture, they get around the owner by filling a civil suit against the property itself, which of course has no pesky civil rights.

  • I guess that’s what I intended as my point, it has an owner who does have rights in their person and effects…