The authority of a search warrant is the best assurance that a search
will be deemed reasonable by the courts and, accordingly, law enforcement
officers should obtain a warrant prior to conducting a search. In accordance
with established legal precedent, however, law enforcement officers may
conduct searches without a warrant if—
(1) the search is incident to an arrest;
(2) the search is conducted upon consent;
(3) the search is conducted under emergency or exigent circumstances;
or
(4) the subject of the search has no reasonable expectation of privacy in
the area or thing to be searched.
