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 decision of the U.S. Supreme Court in which the Court ruled that the exclusionary rule, which prevents prosecutors from using evidence in court that was obtained by violating the Fourth Amendment to the U.S. Constitution, applies not only to the federal government but also to the U.S. state governments. 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's due process clause which is applicable to actions of the states.
Search and seizure is a procedure used in many civil law and common law legal systems by which police or other authorities and their agents, who, suspecting that a crime has been committed, commence a search of a person's property and confiscate any relevant evidence found in connection to the crime.
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 Fourteenth 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). That landmark case made history as 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.
Stanley v. Georgia, 394 U.S. 557 (1969), was a U.S. 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.
Olmstead v. United States, 277 U.S. 438 (1928), was a decision of the Supreme Court of the United States, on the matter of whether wiretapping of private telephone conversations, obtained by federal agents without a search warrant and subsequently used as evidence, constituted a violation of the target’s rights under the Fourth and Fifth Amendments. In a 5–4 decision, the Court held that the Constitutional rights of a wiretapping target have not been violated. This decision was overturned by Katz v. United States in 1967.
In United States law, the Aguilar–Spinelli test 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, Vermont, Oregon, and Washington have retained the Aguilar–Spinelli test, based on their own state constitutions.
United States v. Grubbs, 547 U.S. 90 (2006), was a case decided by the Supreme Court of the United States involving the constitutionality of "anticipatory" search warrants under the Fourth Amendment to the United States Constitution. The Court ruled that such warrants, which are issued in advance of a "triggering condition" that makes them executable, are constitutional and do not need to describe that condition on their face.
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.
Suppression of evidence is a term used in the United States legal system to describe the lawful or unlawful act of preventing evidence from being shown in a trial. This could happen for several reasons. For example, if a judge believes that the evidence in question was obtained illegally, the judge can rule that it not be shown in court. It could also refer to a prosecutor improperly or intentionally hiding evidence that does not go with their case and could suggest or prove to the judge or jury that the defendant is not guilty or that (s)he is legally obligated to show the defense. In the latter case, this would be a violation of the 5th amendment to the United States Constitution. Also Rule 3.8 of the ABA Model Rules of Professional Conduct requires prosecutors to "make timely disclosure to the defense of all evidence or information that tends to negate the guilt of the accused or mitigates the offense." This can result in a mistrial in the latter case and/or the dismissal of the prosecutor.
Inevitable discovery is a doctrine in United States criminal procedure that permits admission of evidence that was obtained through illegal means if it would "inevitably" have been obtained regardless of the illegality. It is one of several exceptions to the exclusionary rule, or the related fruit-of-the-poisonous tree doctrine, which prevent evidence collected in violation of a defendant's constitutional rights from being admitted in court.
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.
Schmerber v. California, 384 U.S. 757 (1966), was a landmark United States Supreme Court case in which the Court clarified the application of the Fourth Amendment's protection against warrantless searches and the Fifth Amendment right against self-incrimination for searches that intrude into the human body. Until Schmerber, the Supreme Court had not yet clarified whether state police officers must procure a search warrant before taking blood samples from criminal suspects. Likewise, the Court had not yet clarified whether blood evidence taken against the wishes of a criminal suspect may be used against that suspect in the course of a criminal prosecution.
United States v. Knotts, 460 U.S. 276 (1983), was a United States Supreme Court case regarding the use of an electronic surveillance device. The defendants argued that the use of this device was a Fourth Amendment violation. The device in question was described as a beeper that could only be tracked from a short distance. During a single trip, officers followed a car containing the beeper, relying on beeper signal to determine the car's final destination. The Court unanimously held that since the use of such a device did not violate a legitimate expectation of privacy there was no search and seizure and thus the use was allowed without a warrant. It reasoned that a person traveling in public has no expectation of privacy in one's movements. Since there was no search and seizure there was not a Fourth Amendment violation.
Pennsylvania v. Mimms, 434 U.S. 106 (1977), is a United States Supreme Court criminal law decision holding that a police officer ordering a person out of a car following a traffic stop and conducting a pat-down to check for weapons did not violate the Fourth Amendment to the United States Constitution.
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.
Utah v. Strieff, 579 U.S. 232, 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.
Carroll v. United States, 354 U.S. 394 (1957), was a case dealing with the appealability of a suppression order issued by the Federal District Court for the District of Columbia for an unlawful warrant under the Fourth Amendment.
Stone v. Powell, 428 U.S. 465 (1976), was decision of the Supreme Court of the United States that limited which claims of Fourth Amendment violations could be made by state prisoners in habeas corpus petitions in federal courts. Specifically, a claim that the exclusionary rule had been broken would be barred if state courts had already given it a full and fair hearing. The decision combined two cases that were argued before the Supreme Court on the same day with similar issues, one filed by Lloyd Powell and the other, titled Wolff v. Rice, filed by David Rice.
