Also known as: knock and announce doctrine · knock-and-announce doctrine · knock and announce rule · knock-and-announce rule · knock-and-announce · Wilson v. Arkansas
Written by attorneys · grounded in primary & secondary sources — see below
A Fourth Amendment principle requiring law enforcement officers to knock and announce their presence and purpose before forcing entry to execute a search warrant unless exigent circumstances justify immediate entry. Violation of the requirement does not trigger the exclusionary rule because the interests protected remain too attenuated from the later evidentiary use of items seized under a valid warrant.
Narcotics officers obtained a warrant for Dana's apartment. They forced the door without knocking or announcing and seized pill bottles inside. Dana moved to suppress the evidence solely on the manner of entry. The court denied the motion because the violation supplied no basis for exclusion of items seized under the valid warrant.
Detectives followed Paul to his residence and observed him inside on the phone. They entered through an unlocked side door without knocking or announcing and arrested him. Paul moved to suppress statements made after the entry. The court evaluated whether the absence of an arrest warrant rendered the entry unconstitutional under the circumstances shown.
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Officers saw a juvenile strike an adult inside a kitchen. They entered the home without knocking or announcing to stop the assault. The adult moved to suppress evidence discovered after entry. The court assessed whether the visible violence supplied an objectively reasonable basis for immediate entry.
An officer stopped Strieff without reasonable suspicion and learned of an outstanding warrant. The officer then arrested Strieff and discovered drugs during a search incident to arrest. Strieff moved to suppress the drugs. The court examined whether the discovery of the warrant sufficiently attenuated the connection between the initial stop and the evidence.
Officers stopped a vehicle for a minor traffic violation they suspected was a pretext for a drug investigation. They observed drugs in plain view during the stop. The driver moved to suppress the drugs. The court considered whether the officers' subjective motive affected the constitutionality of the stop supported by probable cause.
Officers arrested McNeely for drunk driving and directed a warrantless blood draw at the hospital. McNeely moved to suppress the blood test results. The court evaluated whether the natural dissipation of alcohol in the bloodstream created a per se exigency justifying the warrantless procedure.
No. The exclusionary rule does not apply because the interests protected by the knock-and-announce requirement remain too attenuated from the later evidentiary use of the items seized. Alternative remedies such as civil suits and internal discipline supply adequate deterrence.
The requirement protects life, property, privacy, and dignity by giving occupants notice and an opportunity to answer the door peacefully before officers force entry.
Officers may enter without knocking or announcing when exigent circumstances, such as imminent destruction of evidence or danger to officers, make immediate entry reasonable.
The rule applies to dwellings and also extends to commercial premises where occupants hold a reasonable expectation of privacy, though the expectation may be diminished in heavily regulated businesses.
…requisite constitutional (say, warrant or knock-andannounce) compliance. Cf. Mericli, The Apprehension of Peril Exception to the Knock and Announce Rule—Part I, 16 Search and Seizure L. Rep. 129, 130 (1989) (hereinafter Mericli) (noting that some "[d]rug enforcement authorities believe that safety for the police lies in a swift, surprising…