The Fourth Amendment to the United States Constitution is part of the Bill of Rights. It prohibits unreasonable searches and seizures and 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.
The Omnibus Crime Control and Safe Streets Act of 1968 was legislation passed by the Congress of the United States and signed into law by President Lyndon B. Johnson that established the Law Enforcement Assistance Administration (LEAA). Title III of the Act set rules for obtaining wiretap orders in the United States. The act was a major accomplishment of Johnson's war on crime.
United States v. Ross, 456 U.S. 798 (1982), was a search and seizure case argued before the Supreme Court of the United States. The high court was asked to decide if a legal warrantless search of an automobile allows closed containers found in the vehicle to be searched as well. The appeals court had previously ruled that opening and searching the closed portable containers without a warrant was a violation of the Fourth Amendment, even though the warrantless vehicle search was permissible due to existing precedent.
The open-fields doctrine, in the U.S. law of criminal procedure, is the legal doctrine that a "warrantless search of the area outside a property owner's curtilage" does not violate the Fourth Amendment to the United States Constitution. However, "unless there is some other legal basis for the search," such a search "must exclude the home and any adjoining land that is within an enclosure or otherwise protected from public scrutiny."
United States v. Verdugo-Urquidez, 494 U.S. 259 (1990), was a United States Supreme Court decision that determined that Fourth Amendment protections do not apply to searches and seizures by United States agents of property owned by a nonresident alien in a foreign country.
Katz v. United States, 389 U.S. 347 (1967), was a landmark decision of the U.S. Supreme Court in which the Court redefined what constitutes a "search" or "seizure" with regard to the protections of the Fourth Amendment to the U.S. Constitution. The ruling expanded the Fourth Amendment's protections from an individual's "persons, houses, papers, and effects", as specified in the Constitution's text, to include any areas where a person has a "reasonable expectation of privacy". The reasonable expectation of privacy standard, now known as the Katz test, was formulated in a concurring opinion by Justice John Marshall Harlan II.
Florida v. Riley, 488 U.S. 445 (1989), was a United States Supreme Court decision which held that police officials do not need a warrant to observe an individual's property from public airspace.
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, conducted by federal agents without a search warrant with recordings 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.
United States v. U.S. District Court, 407 U.S. 297 (1972), also known as the Keith Case, was a landmark United States Supreme Court decision that upheld, in a unanimous 8-0 ruling, the requirements of the Fourth Amendment in cases of domestic surveillance targeting a domestic threat.
Smith v. Maryland, 442 U.S. 735 (1979), was a Supreme Court case holding that the installation and use of a pen register by the police to obtain information on a suspect's telephone calls was not a "search" within the meaning of the Fourth Amendment to the United States Constitution, and hence no search warrant was required. In the majority opinion, Justice Harry Blackmun rejected the idea that the installation and use of a pen register constitutes a violation of the suspect's reasonable expectation of privacy since the telephone numbers would be available to and recorded by the phone company anyway.
Pearson v. Callahan, 555 U.S. 223 (2009), was a case decided by the United States Supreme Court dealing with the doctrine of qualified immunity.
Bond v United States, 529 U.S. 334 (2000), was a United States Supreme Court Fourth Amendment case that applied the ruling of Minnesota v. Dickerson to luggage, which held that police may not physically manipulate items without a warrant without violating the Fourth Amendment. The Court ruled that this satisfied the two prong test established by Katz v. United States that, (1) a subjective expectation of privacy in the area in question and (2) that the expectation is reasonable in order for the protections of the Fourth Amendment. In this case, the Court ruled that since the Defendant tried to preserve his privacy by using an opaque bag and that it is reasonable for the Defendant to believe that his bag would not be felt in an "exploratory manner" that the two prongs were satisfied.
Ontario v. Quon, 560 U.S. 746 (2010), is a United States Supreme Court case concerning the extent to which the right to privacy applies to electronic communications in a government workplace. It was an appeal by the city of Ontario, California, from a Ninth Circuit decision holding that it had violated the Fourth Amendment rights of two of its police officers when it disciplined them following an audit of pager text messages that discovered many of those messages were personal in nature, some sexually explicit. The Court unanimously held that the audit was work-related and thus did not violate the Fourth Amendment's protections against unreasonable search and seizure.
O'Connor v. Ortega, 480 U.S. 709 (1987), is a United States Supreme Court decision on the Fourth Amendment rights of government employees with regard to administrative searches in the workplace, during investigations by supervisors for violations of employee policy rather than by law enforcement for criminal offenses. It was brought by Magno Ortega, a doctor at a California state hospital after his supervisors found allegedly inculpatory evidence in his office while he was on administrative leave pending an investigation of alleged misconduct. Some of what they uncovered was later used to impeach a witness who testified on his behalf at the hearing where he unsuccessfully appealed his dismissal.
Mancusi v. DeForte, 392 U.S. 364 (1968), is a decision of the United States Supreme Court on privacy and the Fourth Amendment. It originated in the lower courts as United States ex rel. Frank DeForte, appellant v. Vincent R. Mancusi, Warden of Attica Prison, Attica, New York, appellee, a petition for a writ of habeas corpus by a prisoner who had exhausted all his state appeals. By a 6–3 margin the Court affirmed the United States Court of Appeals for the Second Circuit's reversal of a district court denial of the petition.
United States v. Jones, 565 U.S. 400 (2012), was a landmark United States Supreme Court case in which the court held that installing a Global Positioning System (GPS) tracking device on a vehicle and using the device to monitor the vehicle's movements constitutes a search under the Fourth Amendment.
People v. Diaz, 51 Cal. 4th 84, 244 P.3d 501, 119 Cal. Rptr. 3d 105 was a Supreme Court of California case, which held that police are not required to obtain a warrant to search information contained within a cell phone in a lawful arrest. In a sting operation conducted by local police, the defendant, Gregory Diaz, was arrested for the sale of the illicit drug ecstasy and his cellphone, containing incriminating evidence, was seized and searched without a warrant. In trial court proceedings, Diaz motioned to suppress the information obtained from his cellphone, which was denied on the grounds that the search of his cellphone was incident to a lawful arrest. The California Court of Appeal affirmed the court's decision and was later upheld by the California Supreme Court. In 2014, the United States Supreme Court overruled that position in Riley v. California and held that without a warrant, police may not search the digital information on a cellphone that has been seized incident to arrest.
United States v. Graham, 846 F. Supp. 2d 384, was a Maryland District Court case in which the Court held that historical cell site location data is not protected by the Fourth Amendment. Reacting to the precedent established by the recent Supreme Court case United States v. Jones in conjunction with the application of the third party doctrine, Judge Richard D. Bennett found that "information voluntarily disclosed to a third party ceases to enjoy Fourth Amendment protection" because that information no longer belongs to the consumer, but rather to the telecommunications company that handles the transmissions records. The historical cell site location data is then not subject to the privacy protections afforded by the Fourth Amendment standard of probable cause, but rather to the Stored Communications Act, which governs the voluntary or compelled disclosure of stored electronic communications records.
Johnson v. United States, 333 U.S. 10 (1948), was a significant United States Supreme Court decision addressing search warrants and the Fourth Amendment. In this case, where federal agents had probable cause to search a hotel room but did not obtain a warrant, the Court declared the search was "unreasonable."
The aerial surveillance doctrine is the legal doctrine in the United States of America that under the Fourth Amendment, aerial surveillance of an individual’s property does not inherently constitute a search for which law enforcement must obtain a warrant. Courts have used several factors–sometimes only one or a few, other times many or all of them–to determine whether the surveillance in question is a search in violation of one’s constitutional rights: the object of the surveillance, the technology employed, the duration of the surveillance, scope of aggregated information, and the vantage point from which the surveillance is conducted.
