Chatrie v. United States · ¶53

And still another feature of Knotts makes it inapt here: that the surveillance there was confined to public roads. That fact was crucial to the Court’s decision: “A person traveling in an automobile on public thoroughfares has no reasonable expectation of privacy,” Knotts explained, because the car is always “in plain view.” 460 U. S., at 281. By contrast, the movements that Location History reveals are not limited to public streets. Recall what Carpenter observed: A “cell phone faithfully follows its owner beyond public thoroughfares and into private residences, doctor’s offices, [and] political headquarters.” 585 U. S., at 311; see supra, at 15. In one of those places—a private residence—this Court has held even beeper technology to count as a search because it could reveal “whether a particular article—or a person, for that matter” was in the home “at a particular time.” United…

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