Also known as: warrant requirement
Written by attorneys · grounded in primary & secondary sources — see below
A Fourth Amendment principle that favors searches conducted pursuant to a warrant issued by a neutral magistrate. The principle treats warrantless searches as presumptively unreasonable unless a recognized exception applies. It reflects the amendment's command that probable cause determinations receive judicial scrutiny before officers invade protected spaces.
Select any source to read its text and confirm it supports the definition.
Police arrest Wade Watson on an outstanding warrant and bring him to the station. Officers remove his backpack and inventory its contents before placing him in a cell. The backpack yields drug paraphernalia that the prosecution later seeks to introduce. Because the inventory search follows a valid arrest and serves administrative needs, the evidence is admissible even without a warrant.
City inspectors arrive at Wayne Walker's apartment to check for code violations. They lack a warrant and Walker refuses entry. The inspectors return with an administrative warrant supported by area-wide probable cause rather than individualized suspicion. The warrant satisfies the preference because a neutral magistrate reviewed the need for the inspection before entry occurred.
Officers arrest Wren Wright at his home on a murder charge. They then search the entire house and seize clothing and a weapon without obtaining a warrant. A neutral magistrate never reviewed the facts supporting the search. The evidence is suppressed because the officers bypassed the warrant preference by conducting an exploratory search after the arrest was complete.
Federal agents enter Wallace Webb's apartment without a warrant to arrest him for conspiracy. They rely on exigent circumstances but the facts show no immediate threat of evidence destruction. The court suppresses the seized documents because the agents failed to obtain a warrant when time permitted. The preference for judicial review controls absent true exigency.
OSHA inspectors seek to enter Warren Woods's factory for a safety inspection. Woods refuses consent and the inspectors lack a warrant. They return with an administrative warrant based on a general enforcement plan. The warrant satisfies the preference because a magistrate determined that the inspection program justified entry into the commercial premises.
A state trooper stops Wyatt Wilson for speeding and observes a knife on the floorboard. The trooper searches the passenger compartment for additional weapons without a warrant. The search is upheld because the limited intrusion serves officer safety during the roadside encounter. The warrant preference yields to the immediate need for protection rather than a full exploratory search.
Yes. The preference requires inspectors to obtain a warrant before entering a private residence even when the inspection serves a regulatory purpose. The showing of probable cause may be relaxed for area-wide enforcement plans, but judicial review remains necessary.
Officers may proceed without a warrant only when a specifically established exception applies, such as inventory searches incident to incarceration or exigent circumstances. The preference treats all other warrantless searches as unreasonable.
…to search, and we hold that in the case of a lawful custodial arrest a full search of the person is not only an exception to the warrant requirement of the Fourth Amendment, but is also a reasonable' search under that Amendment." Id. , at 235. See also id. , at 237-238 (POWELL, J., concurring) ("The search incident to arrest is…
…that the police were in hot pursuit. The warrantless search of petitioner's home cannot be sustained under any exception to the warrant requirement
…U. S. 697 (1931) (freedom of the press). With respect to the Fourth Amendment, see Aguilar v. Texas , 378 U. S. 108 (1964) (warrant requirement
…may never be made. In assessing whether the public interest demands creation of a general exception to the Fourth Amendment’s
…which they could view the evidence because their entry was not justified by exigent circumstances or any other exception to the warrant requirement
No. The preference yields when a recognized exception such as the automobile exception or a protective frisk during a Terry stop is present. Officers must still satisfy the elements of the exception rather than rely on the seriousness of the offense alone.
A temporary seizure of luggage is permissible when officers have probable cause and fear the item's disappearance. The preference still requires officers to obtain a warrant before searching the contents once the luggage is secured.
Yes. Employees retain a reasonable expectation of privacy in password-protected personal files even on company servers. Officers must obtain a warrant or valid consent before copying those files.