Chatrie v. United States · ¶50

Still more fundamentally, we have never understood Fourth Amendment protections as kicking in only once an intrusion “goes too far.” Pennsylvania Coal Co. v. Mahon, 260 U. S. 393, 415 (1922) (adopting that approach for regulatory takings). Where the Fourth Amendment applies, it applies—regardless of “the quality or quantity of information” the government obtains. Kyllo, 533 U. S., at 37. So, for example, this Court held that thermal imaging qualified as a search even though it did not, and was not likely to, detect “private activities” or “intimate details.” Ibid. The Amendment, we analogized, makes “no exception” for the officer “who barely cracks open the front door and sees nothing but the nonintimate rug on the vestibule floor.” Ibid. And likewise, the Amendment does not give agents a pass if their wiretap is of limited duration and thus less likely to intrude on private matters.…

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