was not suspected and who had on his person a
radio transmitter which communicated the statements to another agent
outside the building.[17] Said Justice Jackson for the Court:
"Petitioner relies on cases relating to the more common and clearly
distinguishable problems raised where tangible property is unlawfully
seized. Such unlawful seizure may violate the Fourth Amendment, even
though the entry itself was by subterfuge or fraud rather than force.
But such decisions are inapposite in the field of mechanical or
electronic devices designed to overhear or intercept conversation, at
least where access to the listening post was not obtained by illegal
methods."[18] But narcotics seized in a hotel room during absence of the
owner, in the course of a search without warrant for either search or
arrest, were not adducible as evidence against the owner, who, however,
was not entitled to have them returned since they were legal
contraband.[19]

Necessity, Sufficiency and Effect of Warrants

A warrant of commitment by a justice of the peace must state a good
cause certain and be supported by oath.[20] A notary public is not
authorized to administer oaths in federal criminal proceedings; hence a
warrant based on affidavits verified before a notary is invalid.[21] A
warrant of the Senate for attachment of a person who ignored a subpoena
from a Senate committee is supported by oath within the requirement of
this amendment when based upon the committee's report of the facts of
the contumacy, made on the committee's own knowledge and having the
sanction of the oath of office of its members.[22]

A belief, however well founded, that an article sought is concealed in a
dwelling house furnishes no justification for a search without a
warrant.[23] A warrant issued upon an information stating only that
"affiant has good reason to believe and does believe" that defendant has
contraband materials in his possession is clearly bad under the Fourth
Amendment.[24] It is enough, however, if the apparent facts set out in
the affidavit are such that a reasonably discreet and prudent man would
be led to believe that the offense charged had been committed.[25]

The requirement of the Fourth Amendment that warrants shall particularly
describe the things to be seized makes general searches under them
impossible and prevents the seizure of one thing under a warrant
describing another. As to what is to be taken nothing is left to the
discretion of