NOTE: Where it is feasible, a syllabus (headnote) will be released, as is being done in connection with this case, at the time the opinion is issued. The syllabus constitutes no part of the opinion of the Court but has been prepared by the Reporter of Decisions for the convenience of the reader. See United States v. Detroit Lumber Co., 200 U. S. 321, 337.

SUPREME COURT OF THE UNITED STATES

Syllabus

WILSON v. ARKANSAS

certiorari to the supreme court of arkansas

No. 94–5707. Argued March 28, 1995—Decided May 22, 1995

Petitioner was convicted on state-law drug charges after the Arkansas trial court denied her evidence-suppression motion, in which she asserted that the search of her home was invalid because, inter alia, the police had violated the common-law principle requiring them to announce their presence and authority before entering. The State Supreme Court affirmed, rejecting petitioner's argument that the common-law ``knock and announce'' principle is required by the Fourth Amendment.

Held: The common-law knock-and-announce principle forms a part of the Fourth Amendment reasonableness inquiry. Pp. 3–10.

(a) An officer's unannounced entry into a home might, in some circumstances, be unreasonable under the Amendment. In evaluating the scope of the constitutional right to be secure in one's house, this Court has looked to the traditional protections against unreasonable searches and seizures afforded by the common law at the time of the framing. Given the longstanding common-law endorsement of the practice of announcement, and the wealth of founding-era commentaries, constitutional provisions, statutes, and cases espousing or supporting the knock-and-announce principle, this Court has little doubt that the Amendment's Framers thought that whether officers announced their presence and authority before entering a dwelling was among the factors to be considered in assessing a search's reasonableness. Nevertheless, the common-law principle was never stated as an inflexible rule requiring an nouncement under all circumstances. Countervailing law enforcement inter ests—including, e.g., the threat of physical harm to police, the fact that an officer is pursuing a recently escaped arrestee, and the existence of reason to believe that evidence would likely be destroyed if advance notice were given—may establish the reasonableness of an unannounced entry. For now, this Court leaves to the lower courts the task of determining such relevant countervailing factors. Pp. 7–9.

(c) Respondent's asserted reasons for affirming the judgment below—that the police reasonably believed that a prior announcement would have placed them in peril and would have produced an unreasonable risk that petitioner would destroy easily disposable narcotics evidence—may well provide the necessary justification for the unannounced entry in this case. The case is remanded to allow the state courts to make the reasonableness determination in the first instance. P. 10.

317 Ark. 548, 878 S. W. 2d 755, reversed and remanded.

Thomas, J., delivered the opinion for a unanimous Court.