At a bare minimum, Katz must be read to require that monitoring of this sort be conducted only pursuant to a warrant: "Over and again this Court has emphasized that the mandate of the [Fourth] Amendment requires adherence to judicial processes,' United States v. Jeffers, 342 U.S. 48, 51, 72 S. Ct. 93, 96 L. Ed. 59, and that searches conducted outside the judicial process, without prior approval by judge or magistrate, are per se unreasonable under the Fourth Amendmentâsubject only to a few specifically established and well-delineated exceptions.' 389 U.S., at 357, 88 S. Ct. 507 (footnotes omitted). In the absence of such judicial supervision, there is no effective safeguard against the possibility of an uncontrolled electronic police state.
In my view the Executive Branch acts unlawfully when it invades an individual's privacy through trickery or fraud. See, e. g., Lewis v. United States, 385 U.S. 206, 344-347, 87 S. Ct. 424, 17 L. Ed. 2d 312 (Douglas, J., dissenting); Hoffa v. United States, 385 U.S. 293, 347-348, 87 S. Ct. 408, 17 L. Ed. 2d 374 (separate opinion of Douglas, J.). The dangers posed by such invasions become particularly acute, however, when they are achieved through or accompanied by electronic monitoring of the sort presented here.
I would grant certiorari.