John Marshall Harlan II,
Katz v. United States (389 U.S. 347…
“ United States, 265 U.S. 57, 44 S.Ct. 445, 68 L.Ed. 898, a person has a constitutionally protected reasonable expectation of privacy; (b) that electronic as well as physical intrusion into a place that is in this sense private may constitute a violation of the Fourth Amendment; and (c) that the invasion of a constitutionally protected area by federal authorities is, as the Court has long held, presumptively unreasonable in the absence of a search warrant. ”
