Warrantless ''National Security'' Electronic Surveillance .--
In Katz v. United States, 151 Justice White sought to preserve for a future case the possibility that in ''national security cases'' electronic surveillance upon the authorization of the President or the Attorney General could be permissible without prior judicial approval. The Executive Branch then asserted the power to wiretap and to ''bug'' in two types of national security situations, against domestic subversion and against
foreign intelligence operations, first basing its authority on a theory of ''inherent'' presidential power and then in the Supreme Court withdrawing to the argument that
such surveillance was a ''reasonable'' search and seizure and therefore valid under the Fourth Amendment. Unanimously, the Court held that at least in cases of
domestic subversive investigations, compliance with the warrant provisions of the Fourth Amendment was required. 152 Whether or not a search was reasonable, wrote Justice Powell for the Court, was a question which derived much of its answer from the warrant clause; except in a few narrowly circumscribed classes of situations,
only those searches conducted pursuant to warrants were reasonable. The Government's duty to preserve the
national security did not override the gurarantee that before government could invade the privacy of its citizens it must present to a neutral magistrate evidence sufficient to support issuance of a warrant authorizing that invasion of privacy. 153 This protection was even more needed in ''national security cases'' than in cases of ''ordinary'' crime, the Justice continued, inasmuch as the
tendency of government so often is to regard opponents of its policies as a threat and hence to tread in areas protected by the First Amendment as well as by the Fourth. 154 Rejected also was the argument that courts could not appreciate the intricacies of investigations in the area of national security nor preserve the secrecy which is required. 155
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