Also known as: 4th Amendment · U.S. Const. amend. IV · search and seizure clause
Written by attorneys · grounded in primary & secondary sources — see below
The constitutional amendment ratified in 1791 that protects individuals against unreasonable searches and seizures by government officials and requires warrants to be supported by probable cause.
Francisco Frost was observed by an officer committing a minor traffic offense punishable only by a fine while driving through an intersection. The officer arrested Frost on the spot without obtaining a warrant. Frost challenged the arrest as violating the Fourth Amendment. The court upheld the arrest because the offense occurred in the officer's presence.
Fatima Flores heard officers knock at her door and immediately began flushing evidence down the toilet. The officers entered without a warrant upon hearing the sounds of destruction. Flores moved to suppress the recovered items. The court admitted the evidence because the officers reasonably believed destruction was imminent and had not created the exigency themselves.
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Fumiko Fujimoto was prosecuted in state court after officers conducted an unconstitutional search of her vehicle. The state sought to introduce the seized items at trial. Fujimoto moved to suppress under the Fourth Amendment. The court excluded the evidence because the exclusionary rule applies to state proceedings through the Fourteenth Amendment.
Frank Fisher placed personal papers inside a public phone booth and closed the door before making a call. Officers listened to the conversation without a warrant. Fisher moved to suppress the recording. The court held that the Fourth Amendment protected his reasonable expectation of privacy even though the booth was in a public location.
Forrest Falconer alleged that federal narcotics agents conducted an unreasonable search of his apartment without a warrant. He filed a civil suit seeking damages for the violation. The agents moved to dismiss on immunity grounds. The court recognized an implied cause of action under the Fourth Amendment for the constitutional violation.
Faye Fuller owned coastal property subject to new state environmental restrictions that barred all development. She sued the state agency claiming the rules effected a taking. The court analyzed whether the restrictions deprived her of all economically viable use under constitutional standards.
Yes. The exclusionary rule prohibits the use of evidence obtained through Fourth Amendment violations in state court proceedings. It is incorporated through the Fourteenth Amendment's Due Process Clause to deter police misconduct.
The reasonable expectation of privacy test applies. A person must exhibit an actual subjective expectation of privacy that society recognizes as objectively reasonable. Government action violating that expectation amounts to a search under the Fourth Amendment.
Officers may enter when they reasonably believe evidence is being destroyed and the exigency was not created by their own Fourth Amendment violation. The entry remains valid even if the exigency arises after officers knock and announce.
Yes. A warrantless arrest is permitted for a misdemeanor committed in the officer's presence even when the offense carries no possibility of incarceration.
…is the "privacy" that the Court finds here even a distant relative of the freedom from searches and seizures protected by the Fourth Amendment to the Constitution, which the Court has referred to as embodying a right to privacy. Katz v. United States , 389 U. S. 347 (1967). If the Court means by the term "privacy" no more than…