Chatrie v. United States · ¶147

The majority reaches the opposite outcome, and in doing so, it announces a new rule of Fourth Amendment law: The police must obtain a warrant every time they access any cell-phone location information from a third party, however brief the duration, however innocuous the request, and however voluntarily that information was disclosed by the user. Ante, at 29. This rule significantly extends Carpenter and repudiates the boundary lines that Carpenter drew to distinguish its novel holding from longstanding doctrine. Whereas Carpenter rested its holding on the difference between obtaining a “brief stretch” of location information and receiving a chronicle spanning a week or more, 585 U. S., at 310, 315, the majority holds that the police need a warrant regardless of the duration of the data sought, ante, at 18– 23. Whereas Carpenter rested its holding on the concern that an all-encompassing…

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