The right of the people to be secure in their persons, houses,papers and effects , against unseasonable searches and seizures , shall not be violated and no warrants shall issue but upon probable cause, supported by oath or affirmation and particularly describing the place to be searched and the persons or things to be seized.
A search and seizure by a law enforcement officer without a search warrant and without probable cause to believe that evidence of a crime is present. Such a search or seizure is unconstitutional under the Fourth Amendment (applied to the states by the Fourteenth Amendment), and evidence obtained from the unlawful search may not be introduced in court.
Under the Fourth Amendment, law enforcement must receive written permission from a court of law, or otherwise qualified magistrate, to lawfully search and seize evidence while investigating criminal activity. A court grants permission by issuing a writ known as a warrant. A search or seizure is generally unreasonable and unconstitutional if conducted without a valid warrant and the police must obtain a warrant whenever practicable. Searches and seizures without a warrant are not considered unreasonable if one of the specifically established and well-delineated exceptions to the warrant requirement applies.
The Supreme Court has held
that individuals in automobiles have a reduced expectation of privacy, because
vehicles generally do not serve as residences or repositories of personal
effects. Vehicles may not be randomly stopped and searched; there must be probable
cause or reasonable suspicion of criminal activity. Items in plain view may be
seized; areas that could potentially hide weapons may also be searched. With
probable cause to believe evidence is present, police officers may search any
area in the vehicle. However, they may not extend the search to the vehicle's
passengers without probable cause to search those passengers or consent from