The Fourth Amendment to the United States Constitution is part of the Bill of Rights. It prohibits unreasonable searches and seizures. In addition, it sets requirements for issuing warrants: warrants must be issued by a judge or magistrate, justified by probable cause, supported by oath or affirmation, and must particularly describe the place to be searched and the persons or things to be seized.
Mapp v. Ohio, 367 U.S. 643 (1961), was a landmark case in criminal procedure, in which the United States Supreme Court decided that evidence obtained in violation of the Fourth Amendment, which protects against "unreasonable searches and seizures," may not be used in state law criminal prosecutions in state courts, as well as in federal criminal law prosecutions in federal courts as had previously been the law. The Supreme Court accomplished this by use of a principle known as selective incorporation; in Mapp this involved the incorporation of the provisions, as interpreted by the Court, of the Fourth Amendment which is applicable only to actions of the federal government into the Fourteenth Amendment due process clause which is applicable to actions of the states.
In the United States, the exclusionary rule is a legal rule, based on constitutional law, that prevents evidence collected or analyzed in violation of the defendant's constitutional rights from being used in a court of law. This may be considered an example of a prophylactic rule formulated by the judiciary in order to protect a constitutional right. The exclusionary rule may also, in some circumstances at least, be considered to follow directly from the constitutional language, such as the Fifth Amendment's command that no person "shall be compelled in any criminal case to be a witness against himself" and that no person "shall be deprived of life, liberty or property without due process of law".
Wolf v. Colorado, 338 U.S. 25 (1949), was a United States Supreme Court case in which the Court held 6-3 that, while the Fourth Amendment was applicable to the states, the exclusionary rule was not a necessary ingredient of the Fourth Amendment's right against warrantless and unreasonable searches and seizures. In Weeks v. United States, 232 U.S. 383 (1914), the Court held that as a matter of judicial implication the exclusionary rule was enforceable in federal courts but not derived from the explicit requirements of the Fourth Amendment. The Wolf Court decided not to incorporate the exclusionary rule as part of the Fourth Amendment in large part because the states which had rejected the Weeks Doctrine had not left the right to privacy without other means of protection. However, because most of the states' rules proved to be ineffective in deterrence, the Court overruled Wolf in Mapp v. Ohio, 367 U.S. 643 (1961). This landmark case made the exclusionary rule enforceable against the states through the Due Process clause of the Fourteenth Amendment to the same extent that it applied against the federal government.
Weeks v. United States, 232 U.S. 383 (1914), was a United States Supreme Court case in which the Court unanimously held that the warrantless seizure of items from a private residence constitutes a violation of the Fourth Amendment. It also prevented local officers from securing evidence by means prohibited under the federal exclusionary rule and giving it to their federal colleagues. It was not until the case of Mapp v. Ohio, 367 U.S. 643 (1961), that the exclusionary rule was deemed to apply to state courts as well.
Stanley v. Georgia, 394 U.S. 557 (1969), was a United States Supreme Court decision that helped to establish an implied "right to privacy" in U.S. law, in the form of mere possession of obscene materials.
California v. Greenwood, 486 U.S. 35 (1988), was a case in which the Supreme Court of the United States held that the Fourth Amendment does not prohibit the warrantless search and seizure of garbage left for collection outside the curtilage of a home.
United States v. Leon, 468 U.S. 897 (1984), was a United States Supreme Court case in which the Court established the "good faith" exception to the Fourth Amendment exclusionary rule.
Illinois v. Gates, 462 U.S. 213 (1983), is a Fourth Amendment case. Gates overruled Aguilar v. Texas and Spinelli v. United States, thereby replacing the Aguilar–Spinelli test for probable cause with the "totality of the circumstances" test.
The Aguilar–Spinellitest was a judicial guideline set down by the U.S. Supreme Court for evaluating the validity of a search warrant or a warrantless arrest based on information provided by a confidential informant or an anonymous tip. The Supreme Court abandoned the Aguilar–Spinelli test in Illinois v. Gates, 462 U.S. 213 (1983), in favor of a rule that evaluates the reliability of the information under the "totality of the circumstances." However, Alaska, Hawaii, Massachusetts, New York, Tennessee, Vermont, Oregon, and Washington have retained the Aguilar–Spinelli test, based on their own state constitutions.
Hudson v. Michigan, 547 U.S. 586 (2006), is a United States Supreme Court case in which the Court held that a violation of the Fourth Amendment requirement that police officers knock, announce their presence, and wait a reasonable amount of time before entering a private residence does not require suppression of the evidence obtained in the ensuing search.
Arizona v. Evans, 514 U.S. 1 (1995), was a United States Supreme Court case in which the Court instituted an exclusionary rule exception allowing evidence obtained through a warrantless search to be valid when a police record erroneously indicates the existence of an outstanding warrant due to negligent conduct of a Clerk of Court.
Silverthorne Lumber Co. v. United States, 251 U.S. 385 (1920), was a U.S. Supreme Court Case in which Silverthorne attempted to evade paying taxes. Federal agents illegally seized tax books from Silverthorne and created copies of the records. The issue in this case is whether or not derivatives of illegal evidence are permissible in court. The ruling, delivered by Oliver Wendell Holmes, Jr., was that to permit derivatives would encourage police to circumvent the Fourth Amendment, so the illegal copied evidence was held tainted and inadmissible. This precedent later became known as the "fruit of the poisonous tree doctrine," and is an extension of the exclusionary rule.
California v. Ciraolo, 476 U.S. 207 (1986), was a case decided by the United States Supreme Court, in which it ruled that warrantless aerial observation of a person's backyard did not violate the Fourth Amendment to the United States Constitution.
Herring v. United States, 555 U.S. 135 (2009), was a case decided by the Supreme Court of the United States on January 14, 2009. The court decided that the good-faith exception to the exclusionary rule applies when a police officer makes an arrest based on an outstanding warrant in another jurisdiction, but the information regarding that warrant is later found to be incorrect because of a negligent error by that agency.
United States v. Payner, 447 U.S. 727 (1980), is a United States Supreme Court case in which the Court reversed a district court's suppression of evidence in the criminal prosecution of an Ohio businessman charged with tax evasion. The case concerned both issues of criminal procedure and the application of the exclusionary rule derived from the Fourth Amendment. By a 6–3 margin the Court both reaffirmed its earlier rulings' holding that only the party whose Fourth Amendment protections may have been violated has standing to challenge the evidence seized in the search, and barred lower courts from exercising their supervisory power to exclude such evidence at the trial of third parties.
Elkins v. United States, 364 U.S. 206 (1960), was a US Supreme Court decision that held the "silver platter doctrine", which allowed federal prosecutors to use evidence illegally gathered by state police, to be a violation of the Fourth Amendment to the United States Constitution.
Murray v. United States, 487 U.S. 533 (1988), was a United States Supreme Court decision that created the modern "independent source doctrine" exception to the exclusionary rule. The exclusionary rule makes most evidence gathered through violations of the Fourth Amendment to the United States Constitution inadmissible in criminal trials as "fruit of the poisonous tree". In Murray, the Court ruled that when officers conduct two searches, the first unlawful and the second lawful, evidence seized during the second search is admissible if the second search "is genuinely independent of [the] earlier one."
Utah v. Strieff, 579 U.S. ___, 136 S. Ct. 2056 (2016), was a case in which the Supreme Court of the United States limited the scope of the Fourth Amendment's exclusionary rule.
Collins v. Virginia, No. 16-1027, 584 U.S. ___ (2018), was a case before the Supreme Court of the United States involving search and seizure. At issue was whether the Fourth Amendment's automobile exception permits a police officer, uninvited and without a warrant, to enter private property, approach a house, and search a vehicle parked a few feet from the house otherwise visible from off the property. In an 8–1 judgement, the Supreme Court ruled that the automobile exception does not apply to vehicles parked within the home or curtilage of a private homeowner.
