Fourth Amendment to the United States Constitution

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The Bill of Rights in the National Archives.

The Fourth Amendment (Amendment IV) to the United States Constitution is the part of the Bill of Rights which guards against unreasonable searches and seizures. It was designed as a response to the controversial writ of assistance (a type of general search warrant), which was a significant factor behind the American Revolution. Toward that end, the amendment specifically requires search and arrest warrants be judicially sanctioned, supported by probable cause and be limited in scope according to specific information supplied by a person (usually a law enforcement officer) who has sworn by it and is therefore accountable to the issuing court.

In Mapp v. Ohio, 367 U.S. 643 (1961), the Supreme Court ruled the Fourth Amendment to be applicable to the state governments by way of the Due Process Clause of the Fourteenth Amendment. The Supreme Court has said some searches and seizures may violate the Fourth Amendment's reasonableness requirement even when a warrant is permissibly granted.

Text

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation, and particularly describing the place to be searched, and the persons or things to be seized.

Background

English law

See also: Entick v. Carrington

John Wilkes authored pamphlets critical of the British government.

Like many other areas of American law, the Fourth Amendment finds its roots in English legal doctrine, and first identified by Edward Coke in Semayne's case in which he articulated that:^[1]

The house of every one is to him as his castle and fortress, as well for his defence against injury and violence as for his repose.

The case acknowledged that the King did not have unbridled authority to intrude on his subject's dwelling but recognized that, when the appropriate agents were employed, their purpose was lawful and a warrant was obtained, government agents were permitted to conduct searches and seizures.^[2] The following years saw a growth in the intensity of litigation against state officers, who, using general warrants, conducted raids in search of materials relating to John Wilkes' publications attacking both government policies and the King himself. The most famous of these cases involved John Entick, whose home was forcibly entered by the King's Messenger Nathan Carrington, along with others, pursuant to a warrant issued by George Montagu-Dunk, 2nd Earl of Halifax authorizing them “to make strict and diligent search for . . . the author, or one concerned in the writing of several weekly very seditious papers intitled, ‘The Monitor or British Freeholder, No 357, 358, 360, 373, 376, 378, and 380,’″ and seized printed charts, pamphlets and other materials. In the resulting case, Entick v. Carrington, Charles Pratt, 1st Earl Camden ruled that the search and seizure was unlawful as the warrant authorized the seizure of all of Entick's papers, not just the criminal ones and the warrant lacked probable cause to even justify the search. Entick established the English precedent that the executive is limited in intruding on private property by common law.^[2]

Colonial America

In Colonial America, legislation was explicitly written to enforce English revenue gathering policies on customs.^[2] Until 1750, all handbooks for justices of the peace, the issuers of warrants, contained or described only general warrants.^[2] William Cuddihy, Ph.D. in his dissertation entitled The Fourth Amendment: Origins and Original Meaning,^[3] claims there existed a "colonial epidemic of general searches." According to him, up until the 1760s, a "man's house was even less of a legal castle in America than in England" as the authorities possessed almost unlimited power and little oversight.

James Otis

In 1756, the province of Massachusetts enacted legislation that barred the use of general warrants. This represented the first law in American history curtailing the use of seizure power. Its creation largely stemmed from the great public outcry over the Excise Act of 1754, which gave tax collectors unlimited powers to interrogate colonists concerning their use of goods subject to customs and permitted the use of a general warrant known as a writ of assistance, allowing them to search the homes of colonists and seize “prohibited and uncustomed” goods.^[4]

A crisis erupted over the writs of assistance on December 27, 1760 when the news of King George II's October 23 death arrived in Boston. All writs automatically expired six months after the death of the King and would have had to be re-issued under the name of the new King, George III, in order to remain valid.^[5]

In mid-January 1761, a group of over 50 merchants represented by James Otis, petitioned the court to have hearings on the issue. During the five hour hearing on February 23, 1761, Otis vehemently denounced English colonial policies, including their sanction of general warrants and writs of assistance.^[6] However, the court ruled against Otis.^[7] Because of the name he had made for himself in attacking the writs, he was elected to the Massachusetts General Assembly and helped pass legislation requiring that special writs of assistance be “granted by any judge or justice of the peace upon information under oath by any officer of the customs” and barring all other writs. The governor overturned the legislation, finding it contrary to British law and parliamentary sovereignty.^[8] John Adams, who was present in the courtroom when Otis spoke, viewed these events “as the spark in which originated the American Revolution.”^[9]

Seeing the danger general warrants presented, the Virginia Declaration of Rights explicitly forbid the use of general warrants. This prohibition became precedent for the Fourth Amendment:^[10]

That general warrants, whereby any officer or messenger may be commanded to search suspected places without evidence of a fact committed, or to seize any person or persons not named, or whose offense is not particularly described and supported by evidence, are grievous and oppressive and ought not to be granted.^[11][12]

Applicability

In general

The Fourth Amendment specifies that any warrant must be judicially sanctioned for a search or an arrest, in order for such a warrant to be considered reasonable. Warrants must be supported by probable cause and be limited in scope according to specific information supplied by a person (usually a peace officer) who has sworn by it and is therefore accountable to the issuing court.

The Fourth Amendment only applies to governmental actors. It does not guarantee a right to be free from unreasonable searches and seizures conducted by private citizens or organizations.^[13] The Bill of Rights originally only restricted the power of the federal government, but the Supreme Court of the United States has ruled that the Fourth Amendment is applicable to state governments by way of the Due Process Clause of the Fourteenth Amendment.^[14] Moreover, all state constitutions contain an analogous provision.^[15]

The Fourth Amendment applies to criminal law, but not civil law. This was affirmed by the Supreme Court in 1855, in the Murray v. Hoboken Land decision.^[16] The jurisdiction of the federal government in the realm of criminal law was narrow, up until the late 19th century when the Interstate Commerce Act and Sherman Antitrust Act were passed. As criminal jurisdiction of the federal government expanded to include other areas such as narcotics, more questions about the Fourth Amendment came to the Supreme Court.^[17]

The Supreme Court has said that some searches and seizures may violate the Fourth Amendment's reasonableness requirement even if a warrant is supported by probable cause and is limited in scope.^[18] Conversely, the Court has approved routine warrantless seizures, for example "where there is probable cause to believe that a criminal offense has been or is being committed."^[19] Thus, the reasonableness requirement and the warrant requirement are somewhat different.

Regarding the Fourth Amendment's reasonableness requirement, it applies not just to a search in combination with a seizure, but also applies to a search without a seizure, as well as to a seizure without a search.^[20] Hence, the amendment is not limited to protecting elements of privacy or personal autonomy, but rather applies pervasively to virtually all aspects of criminal law. Nevertheless, the amendment is not so broad as to replace other constitutional provisions, such as replacing the Eighth Amendment's ban on "cruel and unusual" punishment with a more sweeping ban on "unreasonable" punishment.

Searches

Not all actions by which governmental authorities obtain information from or about a person constitute a search. Therefore, government action triggers the amendment's protections only when the information or evidence at issue was obtained through a "search" within the meaning of the amendment. If no search occurs, no warrant is required. In general, authorities have searched when they have impeded upon a person's reasonable expectation of privacy.

Reasonable expectation of privacy

In Katz v. United States, 389 U.S. 347 (1967), Justice Harlan issued a concurring opinion articulating the two-part test later adopted by the Court as the definition of a search for Fourth Amendment purposes: (1) governmental action must contravene an individual's actual, subjective expectation of privacy; (2) and that expectation of privacy must be reasonable, in the sense that society in general would recognize it as such.

Probable cause to search

When police conduct a search, the amendment requires that the warrant establishes probable cause to believe that the search will uncover criminal activity or contraband. In other words, they must have legally sufficient reasons to believe a search is necessary. In Carroll v. United States 267 U.S. 132 (1925), the Supreme Court stated that probable cause to search is a flexible, common-sense standard. To that end, the Court ruled in Dumbra v. United States, 268 U.S. 435 (1925), that “the term probable cause...means less than evidence that would justify condemnation[,]” reiterating Carroll's assertion that it merely requires that the facts available to the officer would “warrant a man of reasonable caution in the belief,”^[21] that specific items may be contraband or stolen property or useful as evidence of a crime; it does not demand any showing that such a belief be correct or more likely true than false. A "practical, nontechnical" probability that incriminating evidence is involved is all that is required.^[22] Under Illinois v. Gates, 462 U.S. 213 (1983), the Supreme Court ruled that the reliability of an informant is to be determined based on the "totality of the circumstances."

Stop and frisk

However, in certain circumstances, authorities are permitted to conduct a limited warrantless search on a level of suspicion less than probable cause. In Terry v. Ohio 392 U.S. 1 (1968), the Supreme Court decided that when a policeman "observes unusual conduct" that leads him to reasonably believe "that criminal activity may be afoot" and that the suspicious person has a weapon and is presently dangerous to the policeman or others, he may conduct a "pat-down search" (or "frisk"), to determine whether the person is in fact carrying a weapon. To conduct a frisk, the policeman must be able to point to specific and articulable facts which, taken together with rational inferences from those facts, reasonably warrant his actions.^[23] A vague hunch will not do. Such a search must be temporary and questioning must be limited to the purpose of the stop (i.e., if the policeman stopped you because he had reasonable suspicion to believe that you were driving a stolen car, after confirming that it is not stolen, he cannot force you to answer questions about anything else, such as the possession of contraband).^[24]

Seizures

The amendment proscribes unreasonable seizures of private property as well as persons. A seizure of property occurs when there is some meaningful interference by the police with an individual's possessory interests in that property,^[25] such as when police officers take an item away from a person and keep it to use as evidence of a crime. The Fourth Amendment also protects individuals against unreasonable seizure of their person, including those entailing only a brief detention.^[26]

A seizure is not constituted by merely approaching the individual on the street or in another public place, and asking him questions. In this situation, any voluntary answers to such questions may be offered into evidence in a subsequent criminal prosecution. The person approached, however, is not required to answer any questions and may terminate the contact at any time and walk away.^[27][28] He may not be detained even momentarily without reasonable, objective grounds for doing so; and his refusal to listen or answer does not, without more, furnish those grounds.^[29]

A person is seized within the meaning of the Fourth Amendment only when by means of physical force or show of authority his freedom of movement is restrained, and in the circumstances surrounding the incident, a reasonable person would believe that he was not free to leave.^[29] As long as the police do not convey a message that compliance with their requests is required, the courts will usually consider the police contact to be a "citizen encounter" which falls outside the protections of the Fourth Amendment.^[30] If the police are questioning someone, and they remain free to disregard the questions and walk away, there has been no intrusion upon the person's liberty or privacy, and for Fourth Amendment purposes — there has been no seizure.^[29]

Arrests

Of course, when a person is arrested and taken into police custody, they have been seized (i.e., a reasonable person who is handcuffed and placed in the back of a police car would not think they were free to leave). A person subjected to a routine traffic stop on the other hand, has been seized, but is not "arrested" because traffic stops are a relatively brief encounter and are more analogous to a Terry stop than to a formal arrest.^[31] A police officer does not have the authority to arrest someone for refusing to identify himself when he is not suspected of committing a crime.^[32] A search incidental to an arrest that is not permissible under state law does not violate the Fourth Amendment, if the arresting officer has probable cause.^[33][34]

Citizen's arrest

As mentioned in the introduction, the Fourth Amendment does not apply to private citizens, so in the case of a citizen's arrest, the Fourth Amendment standards are not relevant. However, many states have passed laws that dictate the specific circumstances in which a private citizen may arrest another. Typically, a person can make a citizen's arrest when: (1) a misdemeanor amounting to a public nuisance is committed in the arresting citizen's presence; or (2) a felony has been committed, and the arresting citizen has reasonable cause to believe that the person arrested committed it.^[35]

Probable cause to arrest

Main article: Probable Cause

Under common law, a police officer could arrest an individual if that individual committed a misdemeanor in the officer's presence, or if the officer had probable cause to believe that the individual was committing a felony (i.e., probable cause to believe that someone had committed a misdemeanor does not justify an arrest; the police officer has to actually witness the misdemeanor.)^[31]

The probable cause required for an arrest is different than that required for a search. Police have probable cause to make an arrest when "the facts and circumstances within their knowledge and of which they had reasonably trustworthy information" would lead a prudent person to believe that the arrested person had committed or was committing a crime.^[36] Probable cause to arrest must exist before the arrest is made: evidence discovered after the arrest may not be retroactively used to justify the arrest.^[37]

Warrant requirement

Under the amendment, law enforcement must receive written permission from a court of law, or otherwise qualified magistrate, in order to lawfully search for and seize evidence while investigating criminal activity. A court grants permission by issuing a writ known as a warrant. A search or seizure is generally unreasonable (i.e., unconstitutional) if conducted without a valid warrant,^[38] and the police must obtain a warrant whenever practicable.^[39] Warrantless searches and seizures are not automatically considered to be unreasonable, unless one of the specifically established and well-delineated exceptions to the warrant requirement is applicable.^[40]

Exclusionary rule

Main article: exclusionary rule

One way courts enforce the rights guaranteed by the amendment is with the exclusionary rule. The rule provides that evidence obtained through a violation of the Fourth Amendment is generally not admissible by the prosecution during the defendant's criminal trial.

The Court adopted the exclusionary rule in Weeks v. United States, 232 U.S. 383 (1914), prior to which all evidence, no matter how seized, could be admitted in court. Additionally, in Silverthorne Lumber Co. v. United States, 251 U.S. 385 (1920) and Nardone v. United States, 308 U.S. 338 (1939), the Court ruled that tips resulting from illegally obtained evidence are also inadmissible in trials as fruit of the poisonous tree. The rule serves primarily to deter police officers from willfully violating a suspect's Fourth Amendment rights. The rationale behind the exclusionary rule is that if the police know evidence obtained in violation of the Fourth Amendment cannot be used to convict someone of a crime, they will not violate it. In delivering the opinion of the Court, Justice Frankfurter, in Wolf v. Colorado, 338 U.S. 25 (1949), rejected incorporation of the Fourth Amendment by way of the Fourteenth Amendment. Later, in Mapp v. Ohio, 367 U.S. 643 (1961), the Supreme Court explicitly overruled Wolf and made the Fourth Amendment (including the exclusionary rule) applicable in state proceedings as an essential part of criminal procedure.

Exceptions to the exclusionary rule

As with most legal rules, there are a number of exceptions. In United States v. Calandra, 414 U.S. 338 (1974), the Supreme Court ruled that grand juries may use allegedly illegally obtained evidence in questioning witnesses because, to hold otherwise, would interfere with grand jury independence and the place to contest the illegal search is after the accused is charged. In United States v. Leon, 468 U.S. 897 (1984), the Supreme Court applied the "good faith" rule and held that evidence seized by officers objectively and in good faith relying on a warrant later found to be defective was still admissible. The evidence would still be excluded if an officer dishonestly or recklessly prepares an affidavit forming the basis at the warrant, if the issuing magistrate abandons his neutrality, or if the warrant lacks sufficient particularity. The Leon case applies only to search warrants. It remains unclear whether the "good faith" exception applies to warrantless seizures in other contexts.

The Supreme Court has held the rule does not apply in certain situations: (1) probation or parole revocation hearings; (2) tax hearings; (3) deportation hearings; (4) when government officials illegally seize evidence outside the United States; (5) when a "private actor" (i.e., not a governmental employee) illegally seized the evidence; or (6) when the illegally seized evidence is used to impeach the defendant's testimony. Furthermore, a defendant has standing to object to the admission of unconstitutionally seized evidence only if such seizure violated his own Fourth Amendment rights; a defendant may not assert the rights of a third party. For example, a mere passenger in a car has standing to contest the stop of the car and a search of his person, but he usually lacks standing to contest a search of the car. If he is a passenger in his own car, however, he would have standing to challenge the search of the car.

Exceptions to the warrant requirement

Courts have developed a number of exceptions to the warrant requirement:

Plain view doctrine

Main article: Plain view doctrine

If an officer is lawfully present, he may search and seize objects that are in "plain view". However, before the seizure the officer must have probable cause to believe that the objects are contraband.^[41]

Open fields doctrine

Main article: Open fields doctrine

Similarly, "open fields"—pastures, open water, woods and other such areas—may be searched without a warrant, on the basis that the individuals conducting activities therein had no reasonable expectations of privacy. Contrary to its apparent meaning, the "open fields" doctrine has been expanded to include almost any open space other than the land immediately surrounding a domicile.

The open fields doctrine was first articulated by the Supreme Court in Hester v. United States, 265 U.S. 57 (1924), which stated that “the special protection accorded by the Fourth Amendment to the people in their ‘persons, houses, papers, and effects,’ is not extended to the open fields." This opinion appears to be decided on the basis that "open fields are not a 'constitutionally protected area' because they cannot be construed as "persons, houses, papers, [or] effects."

This method of reasoning gave way with the arrival of the landmark case Katz v. United States, 389 U.S. 347 (1967), which established a two-part test for what constitutes a search within the meaning of the Fourth Amendment. The relevant criteria are "first that a person have exhibited an actual (subjective) expectation of privacy and, second, that the expectation be one that society is prepared to recognize as reasonable." Under this “new” analysis of the Fourth Amendment, privacy expectations deemed unreasonable by society cannot be validated by any steps taken by the defendant to shield the area from view.

In Oliver v. United States, 466 U.S. 170 (1984), the police ignored a "no trespassing" sign, trespassed onto the suspect's land without a warrant, followed a path several hundred yards, and discovered a field of marijuana. The Supreme Court ruled that no search had taken place, because there was no privacy expectation regarding an open field:

…open fields do not provide the setting for those intimate activities that the Amendment is intended to shelter from government interference or surveillance. There is no societal interest in protecting the privacy of those activities, such as the cultivation of crops, that occur in open fields.^[42]

Distinguishing open fields from curtilage

While open fields are not protected by the Fourth Amendment, the curtilage, or outdoor area immediately surrounding the home, is protected. Courts have treated this area as an extension of the house and as such subject to all the privacy protections afforded a person’s home (unlike a person's open fields) under the Fourth Amendment. However, courts have held aerial surveillance of curtilage not to be included in the protections from unwarranted search so long as the airspace above the curtilage is generally accessible by the public.

An area is curtilage if it "harbors the intimate activity associated with the sanctity of a man's home and the privacies of life."^[43] Courts make this determination by examining "whether the area is included within an enclosure surrounding the home, the nature of the uses to which the area is put, and the steps taken by the resident to protect the area from observation by people passing by."^[44] Theoretically, many structures might extend the curtilage protection to the areas immediately surrounding them. The courts have gone so far as to treat a tent as a home for Fourth Amendment purposes in the past.^[45][46][47] It is possible that the area immediately surrounding a tent (or any structure used as a home) might be considered curtilage.

Despite this rather broad interpretation of curtilage, the courts seem willing to find areas to be outside of the curtilage if they are in any way separate from the home (by a fence, great distance, other structures, even certain plants).^[48]

Exigent circumstances

Main article: Exigent circumstances

There are also "exigent circumstances" exceptions to the warrant requirement. Exigent circumstances arise when the law enforcement officers have reasonable grounds to believe that there is an immediate need to protect their lives, the lives of others, their property, or that of others, the search is not motivated by an intent to arrest and seize evidence, and there is some reasonable basis, to associate an emergency with the area or place to be searched.^[49]

Motor vehicle exception

Main article: Motor vehicle exception

The Supreme Court has also held that individuals in automobiles have a reduced expectation of privacy, because vehicles generally do not serve as residences or repositories of personal effects. Vehicles may not be randomly stopped and searched; there must be probable cause or reasonable suspicion of criminal activity. Items in "plain view" may be seized; areas that could potentially hide weapons may also be searched. With probable cause, police officers may search any area in the vehicle. They may not, however, extend the search to the vehicle's passengers without probable cause to search those passengers or consent from the passenger(s) to search their persons or effects.

Searches incident to a lawful arrest

Main article: Searches incident to a lawful arrest

Another common law rule—that permitting searches incident to an arrest without warrant—has been applied in American law. The justification for such a search is that the arrested individual must be prevented from destroying evidence or using a weapon against the arresting officer. In Trupiano v. United States, 334 U.S. 699 (1948), the Supreme Court held that "a search or seizure without a warrant as an incident to a lawful arrest has always been considered to be a strictly limited right. It grows out of the inherent necessities of the situation at the time of the arrest. But there must be something more in the way of necessity than merely a lawful arrest." In United States v. Rabinowitz, 339 U.S. 56 (1950), the Court reversed its previous ruling, holding that the officers' opportunity to obtain a warrant was not germane to the reasonableness of a search incident to an arrest. The decision suggested that any area within the "immediate control" of the arrestee could be searched, but it did not define the term. In deciding Chimel v. California, 395 U.S. 752 (1969), the Supreme Court elucidated its previous decisions. It held that when an arrest is made, it is reasonable for the officer to search the arrestee for weapons and evidence.

Similarly, it was held that it is reasonable for the officer to search the area within the arrestee's immediate control, that is, the area from which the defendant may gain access to a weapon or evidence. A search of the room in which the arrest is made is therefore permissible, but the same is not true of a search of other rooms, as the arrestee would not probably be able to access weapons or evidence in those rooms at the time of arrest.

Border search exception

Main article: Border search exception

Searches conducted at the United States border or the equivalent of the border (such as an international airport) may be conducted without a warrant or probable cause subject to the "border-search" exception.^[50] Most border searches may be conducted entirely at random, without any level of suspicion, pursuant to Customs' plenary search authority. However, searches that intrude upon traveler's personal dignity and privacy interests, including strip and body cavity searches must be supported by 'reasonable suspicion.'^[51] Two federal Courts of Appeals have ruled that information on a traveler's electronic materials, including personal files on a laptop computer, may be searched at random, without suspicion.^[52]

Other exceptions

New Jersey v. T. L. O., 469 U.S. 325 (1985), held that searches in public schools do not require warrants, as long as the searching officers have reasonable grounds for believing that the search will result in the finding of evidence of illegal activity.

Similarly, Samson v. California, 547 U.S. 843 (2006) held that government offices may be searched for evidence of work-related misconduct by government employees on similar grounds. Searches of prison cells are subject to no restraints relating to reasonableness or probable cause or searches undertaken as a condition of parole.

Finally, a search is reasonable if the target without coercion consents to the search, even if the target is unaware and not told about their right to refuse to cooperate.

In a memo dated March 14, 2003, an official in the Bush administration stated "... our Office recently concluded that the Fourth Amendment had no application to domestic military operations". The administration believed that any search or surveillance conducted by the National Security Agency of US citizens communicating with foreign nationals abroad was immune to a Fourth Amendment challenge.^[53] To protect the telecommunication carriers cooperating with the US government from legal action, the Congress passed a bill updating the Foreign Intelligence Surveillance Act of 1978 to permit this type of surveillance.^[54]

The Internet, computers, and privacy

In the last decade courts have had to determine whether law enforcement officials can access evidence of illegal activity stored on digital technology without encroaching on a person's Fourth Amendment rights.

Many cases discuss whether a private employee (i.e., not a government employee) who stores incriminating evidence in workplace computers is protected by the Fourth Amendment's reasonable expectation of privacy standard in a criminal proceeding. However, these cases do not appear to produce a uniform and consistent standard of law. Most case law holds that employees do not have a reasonable expectation of privacy when it comes to their work related electronic communications.^[55] However, one federal court held that employees can assert the attorney-client privilege with respect to certain communications on company laptops.^[56]

On January 30, 2007, the United States Court of Appeals for the Ninth Circuit in United States v. Ziegler, reversed its earlier August 2006 decision upon a petition for rehearing. In contrast to the earlier decision, the Court acknowledged that an employee has a right to privacy in his workplace computer. However, the Court also found that an employer can consent to any illegal searches and seizures.^[57] In Ziegler, an employee had accessed child pornography websites from his workplace. His employer noticed his activities, made copies of the hard drive, and gave the FBI the employee's computer. At his criminal trial, Ziegler filed a motion to suppress the evidence because he argued that the government violated his Fourth Amendment rights. The Ninth Circuit allowed the lower court to admit the child pornography evidence. After reviewing relevant Supreme Court opinions on a reasonable expectation of privacy, the court acknowledged that Ziegler had a reasonable expectation of privacy at his office and on his computer. That court also found that his employer could consent to a government search of the computer, and that did not violate Ziegler's Fourth Amendment rights.

Important cases

Exclusionary Rule

• Weeks v. United States (1914)
• Mapp v. Ohio (1961)
• United States v. Leon (1984)
• Pennsylvania Board of Probation and Parole v. Scott (1998)

Privacy

• Olmstead v. United States (1928)
• Katz v. United States (1967)
• Zurcher v. Stanford Daily (1978)
• United States v. Karo (1984)
• California v. Greenwood (1988)
• Florida v. Riley (1989)
• Kyllo v. United States (2001)
• United States v. White (2003)
• Hepting v. AT&T (2006)
• Hudson v. Michigan (2006)

Informants

• Illinois v. Gates (1983)

Search Warrants

• Franks v. Delaware (1979)
• Maryland v. Garrison (1987)
• Richards v. Wisconsin (1997)
• Groh v. Ramirez (2004)

Arrest and Search of a Person Without a Warrant

• United States v. Watson (1976)
• United States v. Robinson (1973)
• Tennessee v. Garner (1985)
• Whren v. United States (1996)
• Atwater v. City of Lago Vista (2001)

Search of and Seizure from a Residence Without a Warrant

• Chimel v. California (1969)
• Vale v. Louisiana (1970)
• Payton v. New York (1980)
• Steagald v. United States (1981)
• Illinois v. McArthur (2001)

Search and Seizure of Vehicles and Containers Without a Warrant

• Carroll v. United States (1925)
• South Dakota v. Opperman (1976)
• United States v. Chadwick (1977)
• Arkansas v. Sanders (1979)
• New York v. Belton (1981)
• United States v. Ross (1982)
• California v. Carney (1985)
• Colorado v. Bertine (1987)
• California v. Acevedo (1991)
• Knowles v. Iowa (1998)
• Wyoming v. Houghton (1999)
• Thornton v. United States (2004)
• Arizona v. Gant (2008)

Plain-view & Plain-feel

• Arizona v. Hicks (1987)
• Horton v. California (1990)
• Minnesota v. Dickerson (1993)

Stop and Frisk

• Terry v. Ohio (1968)
• Dunaway v. New York (1979)
• Florida v. Royer (1983)
• Michigan v. Long (1983)
• United States v. Place (1983)
• Florida v. J.L. (2000)
• Illinois v. Wardlow (2000)
• United States v. Drayton (2002)
• Hiibel v. Sixth Judicial District Court of Nevada (2004)

Border Searches

• United States v. Thirty-Seven Photographs (1971)
• United States v. Ramsey (1977)
• United States v. Montoya de Hernandez (1985)
• United States v. Flores-Montano (2004)

See also

• Section Eight of the Canadian Charter of Rights and Freedoms
• subpoena duces tecum
• subpoena ad testificandum

References

Further reading

• Amar, Akhil Reed (1994). "Fourth Amendment First Principles". Harvard Law Review 107: 757–819. 
• Amsterdam, Anthony G. (1974). "Perspectives on the Fourth Amendment". Minnesota Law Review 58: 349. 
• Davies, Thomas Y. (1999). "Recovering the Original Fourth Amendment". Michigan Law Review 98: 547. doi:10.2307/1290314. http://www.law.utk.edu/FACULTY/4thamend.pdf. 
• Ducat, Craig R. and Harold W. Chase (Eds) (1992). Constitutional Interpretation (5th Ed. ed.). West Publishing Company. pp. 797–818. 
• Kilman, Johnny and George Costello (Eds) (2006). "The Constitution of the United States of America: Analysis and Interpretation". GPO.
• Lasson, Nelson B. (1937). The History and Development of the Fourth Amendment to the United States Constitution. Johns Hopkins University Press. 
• Levy, Leonard Williams (1995). Seasoned Judgments: The American Constitution, Rights, and History. Transaction Publishers. 

External links

• CRS Annotated Constitution: Fourth Amendment, Cornell University
• Summaries of Recent U.S. Criminal Law Decisions