The Fourth Amendment to the U.S. Constitution reads:
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.
The American Revolution was fought, in part, to create a system of government in which the RULE OF LAW would reign supreme. The rule of law is often identified with the old saying that the United States is a nation of laws and not of men. Under the rule of law, the actions of government officials are prescribed by the principles and laws that make up the U.S. legal system and do not reflect the ARBITRARY whims and caprices of the government officials themselves.
A distinction is sometimes drawn between power and authority. Law enforcement officers are entrusted with the powers to conduct investigations, to make arrests, and occasionally to use lethal force in the line of duty. But these powers must be exercised within the parameters authorized by the law. Power exercised outside of these legal parameters transforms law enforcers into lawbreakers, as happened when Los Angeles police officer Laurence Powell was convicted for using excessive force against RODNEY KING, who had been stopped for speeding. Powell repeatedly struck King with his night-stick even though King was in a submissive position, lying prone on the ground.
The Fourth Amendment was intended to create a constitutional buffer between U.S. citizens and the intimidating power of law enforcement. It has three components. First, it establishes a privacy interest by recognizing the right of U.S. citizens to be "secure in their persons, houses, papers, and effects." Second, it protects this privacy interest by prohibiting SEARCHES AND SEIZURES that are "unreasonable" or are not authorized by a warrant based upon probable cause. Third, it states that no warrant may be issued to a law enforcement officer unless that warrant describes with particularity "the place to be searched, and the persons or things to be seized."
The Framers drafted the Fourth Amendment in response to their colonial experience with British officials, whose discretion in collecting revenues for the Crown often went unchecked. Upon a mere suspicion held by British tax collectors or their informants, colonial magistrates were compelled to issue general warrants, which permitted blanket door-to-door searches of entire neighborhoods without limitation as to person or place. The law did not require magistrates to question British officials regarding the source of their suspicion or to make other credibility determinations.
The writ of assistance was a particularly loathsome form of general warrant. The name of this writ derived from the power of British authorities to enlist local peace officers and colonial residents who might "assist" in executing a particular search. A writ of assistance lasted for the life of the king or queen under whom it was issued, and it applied to every officer and subject in the British Empire. In essence, such a writ was a license for customs officers tracking smugglers and illegally imported goods.
Colonial opposition to general warrants was pervasive and kinetic. In Paxton's Case (also known as the WRITS OF ASSISTANCE CASE), 1 Quincy 51 (Mass. 1761), JAMES OTIS, appearing on behalf of colonists who opposed the issuance of another writ of assistance, denounced general warrants as instruments of "slavery," "villainy," and "arbitrary power." These writs, Otis continued, were "the most destructive of English liberty" because they placed the freedom of every person "in the hands of a petty officer" (as quoted in O'Rourke v. City of Norman, 875 F.2d 1465 [10th Cir. 1989]). In order to be valid, Otis railed, a warrant must be "directed to specific officers, and to search certain houses" for particular goods, and may only be granted "upon oath made" by a government official "that he suspects such goods to be concealed in those very places he desires to search" (as quoted in Illinois v. Krull, 480 U.S. 340, 107 S. Ct. 1160, 94 L. Ed. 2d 364 ).
Although Otis lost the case, his arguments fueled angry colonial crowds that subsequently interfered with British customs and revenue agents who attempted to seize miscellaneous goods pursuant to general warrants. Some provincial courts began declining to issue writs of assistance, and other courts issued writs with greater specificity. Colonial newspapers complained that British officers were ransacking the colonists' houses, violating the sanctity of their bedrooms, and plundering their privacy under the auspices of general warrants. On the night before the Declaration of Independence was published, JOHN ADAMS cited the "argument concerning the Writs of Assistance … as the commencement of the controversy between Great Britain and America."
The American Revolution answered the questions surrounding writs of assistance, but the Fourth Amendment raised other questions in the newly founded republic. If a police officer's suspicion is no longer sufficient to obtain a SEARCH WARRANT, as it was in colonial America, where should the line be drawn separating suspicion from probable cause? Although general warrants are now clearly prohibited, how detailed must warrants be to pass constitutional muster? The Fourth Amendment expressly forbids "unreasonable" searches and seizures, but what criteria should be considered in evaluating the reasonableness of a search? The Fourth Amendment also leaves open the question of who should review warrant applications—the judiciary or some other branch of government. The answers to these questions were explored and developed in criminal litigation over the next two centuries.
Fourth Amendment questions arise during criminal litigation in the context of a suppression hearing. This hearing is prompted by a defendant who asks the court to review the method by which the police obtained evidence against him or her, and to determine whether that evidence survives constitutional scrutiny. If the evidence was obtained in violation of the Fourth Amendment, it usually will be excluded from trial, which means the prosecution will be unable to present it to the jury. The legal doctrine under which illegally obtained evidence is suppressed is known as the EXCLUSIONARY RULE, and its purpose is to deter POLICE MISCONDUCT and to protect defendants from it.
The exclusionary rule requires the suppression not only of evidence that was the direct product of illegal police work but also of any evidence that is derived from a tainted source. The suppression of tainted derivative evidence, also known as FRUIT OF THE POISONOUS TREE, typically occurs when the police obtain a confession after an illegal arrest or pursuant to an unconstitutional search. Although the manner in which the confession itself was obtained may have been perfectly constitutional, the confession is still suppressed because the law does not permit the government, which the prosecution represents at a criminal trial, to benefit from its own misconduct.
Before a court may exclude any evidence, it first must determine whether the Fourth Amendment even applies to the case under consideration. Two requirements must be met before a particular search or seizure will give rise to Fourth Amendment protection. First, the search or seizure must have been conducted by a government agent or pursuant to government direction. Thus, the actions of state and federal law enforcement officers or private persons working with law enforcement officers will be subject to the strictures of the Fourth Amendment. Bugging, WIRE TAPPING, and other related eavesdropping activities performed by purely private citizens, such as private investigators, will not receive Fourth Amendment protection.
Second, a defendant must be able to demonstrate that he or she had a "reasonable expectation of privacy" in the place that was searched or the thing that was seized (Katz v. United States, 389 U.S. 347, 88 S. Ct. 507, 19 L. Ed. 576 ). In Katz, the U.S. Supreme Court explained that "[w]hat a person knowingly exposes to the public, even in his own home or office, is not a subject of Fourth Amendment protection… . Butwhat he seeks to preserve as private, even in an area accessible to the public, may be constitutionally protected."
Applying this principle, the Court has ruled that U.S. citizens maintain a reasonable expectation of privacy in the "curtilage" immediately surrounding their home, but not in the "open fields" and "wooded areas" extending beyond this area (Hester v. United States, 265 U.S. 57, 44S. Ct. 445, 68 L. Ed. 898 ). A person may have a reasonable expectation of privacy in the automobile that he or she is driving, but not in items that are in "plain view" from outside the vehicle (Coolidge v. New Hampshire, 403 U.S. 443, 91 S. Ct. 2022, 29 L. Ed. 564 ). Nor do people have reasonable expectations of privacy in personal characteristics (United States v. Dionisio, 410 U.S. 1, 93 S. Ct. 764, 35 L. Ed. 2d 67). Thus, the police may require individuals to give handwriting and voice exemplars as well as fingerprint samples, without complying with the Fourth Amendment's warrant or reasonableness requirements.
In Minnesota v. Carter, 525 U.S. 83, 119 S. Ct. 469, 142 L. Ed.2d 373 (1998), the U.S. Supreme Court considered whether a police officer who had looked in an apartment window through a gap in a closed window blind had violated the privacy of the drug dealers in the apartment because they had an expectation of privacy that is protected by the Fourth Amendment. The Court held that the police officer had not violated the Fourth Amendment because the occupants of the apartment had not had an expectation of privacy. This was due to the fact the drug dealers had merely used the apartment to consummate business transactions and that they had no personal relationship with the occupant of the apartment.
However, the high court looked at the issue differently when the drug courier's contraband was discovered on a bus by an officer who thought that a bag felt peculiar. In Bond v. U.S., 529 U.S. 334, 120 S. Ct. 1462, 146 L. Ed.2d 365(2000), it ruled that police cannot squeeze the luggage of bus passengers in order to try to find illegal drugs. The ruling forces law enforcement to modify the way they inspect luggage and packages that are carried by, or in the custody of an individual.
The U.S. Supreme Court has made clear that there are limits to high-tech government snooping when the government has the ability to use sophisticated technology to monitor criminal suspects. In Kyllo v. United States, 533 U.S. 27, 121 S. Ct. 2038, 150 L. Ed.2d 94 (2001), the Court ruled that police could not use evidence obtained through the use of thermal imaging without first obtaining a search warrant. It declared that a warrantless search would be regarded as "presumptively unreasonable" and that the evidence that the search produced will be inadmissible at trial. The police had received a tip that Danny Kyllo was growing marijuana inside his home. Because marijuana cultivation requires the use of high-intensity lamps, police used a thermal imager to scan Kyllo's residence. The imager detects infrared radiation, which is invisible to the naked eye. The machine converts the radiation into images based on relative warmth. The police conducted the scan across the street from Kyllo's home, accomplishing the task in just a few minutes. The scan disclosed that one part of his house was substantially hotter than any other unit in his triplex. Based on the scan, utility bills, and tips from informants, police secured a search warrant and found that Kyllo had indeed been growing marijuana.
The U.S. Supreme Court noted that the degree of privacy guaranteed by the Fourth Amendment had been affected by technological developments. The question became "what limits there are upon this power of technology to shrink the realm of guaranteed privacy." In its view, individuals had a "minimum expectation of privacy"that the interiors of their homes were not subject to warrantless police searches."Thus, the use of "sense-enhancing technology" that could obtain information that would otherwise only be obtainable by a physical search constituted a "search." Accordingly, any information obtained by the thermal imager was the product of a search. The Court's analysis led to the legal conclusion that such a search was unreasonable and that it could be justified only if it were made pursuant to a warrant.
Once a court has determined that the Fourth Amendment is an issue in a particular case, it next must decide whether law enforcement complied with the amendment's requirements. When making this decision, a court begins with the premise that the Constitution expresses a preference for searches made pursuant to a warrant (Mincey v. Arizona, 437 U.S. 385, 98 S. Ct. 2408, 57 L. Ed. 2d 290 ). Searches performed without a warrant are presumptively invalid, and evidence seized during a warrantless search is suppressed unless the search was reasonable under the circumstances.
The U.S. Supreme Court has ruled that warrantless searches may be deemed reasonable in certain situations. First, no warrant is required for searches incident to a lawful arrest (United States v. Watson, 423 U.S. 411, 96 S. Ct. 820, 46 L. Ed. 2d 598 ). If a police officer has probable cause to believe that a crime has occurred, the Fourth Amendment permits the officer to arrest the suspect and to conduct a search of the suspect's person and clothing and of all areas within the suspect's immediate reach. Second, a police officer who possesses an "articulable" and "reasonable" suspicion that an automobile has violated a state or local traffic law may stop the driver and conduct a search of the vehicle's interior, including the glove compartment (Delaware v. Prouse, 440 U.S. 648, 99 S. Ct. 1391, 59 L. Ed. 2d 660 ). The trunk of a vehicle cannot be searched unless an officer has probable cause to believe that it contains contraband or the instrumentalities of criminal activity.
Third, an officer who reasonably believes "that criminal activity may be afoot" in a public place may stop an individual who is suspected of wrongdoing and "conduct a carefully limited search of [the suspect's] outer clothing" for weapons that may be used against the officer (TERRY V. OHIO, 392 U.S. 1, 88 S. Ct. 1868, 21 L. Ed. 889 ). Fourth, officers who are in "hot pursuit" of "fleeing felons" or are gathering "evanescent" evidence (evidence that could readily disappear—e.g. blood samples from drunken drivers) are also permitted to act without first obtaining a search warrant.
These four exceptions to the warrant requirement are based on the need to facilitate law enforcement during unforeseen or emergency circumstances in which criminal activity is strongly suspected but police officers lack sufficient time to complete an application for a search warrant and to testify before a magistrate. These exceptions also reflect a need to protect police officers from hidden weapons and to preserve evidence that easily could be destroyed or compromised.
When law enforcement does obtain a warrant before conducting a search, the warrant must comply with the Fourth Amendment before evidence from the search will be admissible in court. A warrant may be defective if it is not supported by probable cause that is established by a detailed, sworn statement made by a law enforcement officer appearing before a magistrate.
No definition of probable cause has ever satisfied both prosecutors and defense attorneys. But the U.S. Supreme Court has said that probable cause exists where "the facts and circumstances within [the police officer's] knowledge" are of a "reasonably trustworthy" basis to "warrant a man of reasonable caution" to believe that an offense has been or is about to be committed (Carroll v. United States, 267 U.S. 132, 45 S. Ct. 280, 69 L. Ed. 543 ). Probable cause can be established by out-of-court statements of reliable police informants even though the credibility of those statements cannot be tested by a magistrate (Illinois v. Gates, 462 U.S. 213, 103 S. Ct. 2317, 76 L. Ed. 2d 527 ). However, probable cause will not be found where the only evidence of criminal activity is an officer's "good information" or "belief" (Aguilar v. Texas, 378U.S. 108, 84 S. Ct. 1509, 12 L. Ed. 2d 723 ).
The Fourth Amendment requires not only that search warrants be supported by probable cause but also that they "particularly" describe the person or place to be searched. A warrant must provide enough detail so that an "officer with the search warrant can, with reasonable effort, ascertain and identify the place [or person] intended" (Steele v. United States, 267 U.S. 498, 45 S. Ct. 414, 69 L. Ed. 757 ). For most residences, a street address usually satisfies the particularity requirement. However, if a warrant designates an apartment complex, hotel, or other multiple-unit building, the warrant must describe the specific sub-unit that will be searched. When a warrant designates that a person will be searched, it must include a description that provides enough detail so that the suspect's identity can be ascertained with reasonable certainty.
Probable cause must be established by testimony made under oath by a law enforcement officer appearing before a magistrate. The testimony can be oral or written, and it cannot contain any "knowingly" or "intentionally" false statements, or statements made in "reckless disregard for the truth" (Franks v. Delaware, 438U.S. 154, 98 S. Ct. 2674, 57 L. Ed. 2d 667 ). Inaccuracies due to NEGLIGENCE or innocent omission do not jeopardize a warrant's validity.
The magistrate before whom an officer applies for a warrant must be "neutral and detached" (Coolidge v. New Hampshire, 403 U.S. 443, 91 S. Ct. 2022, 29 L. Ed. 2d 564 ). This means that the magistrate must be impartial and not a member of the "competitive enterprise" of law enforcement (California v. Acevedo, 500 U.S. 565, 111 S. Ct. 1982, 114 L. Ed. 2d 619 ). Thus, police officers, prosecutors, and attorneys general are disqualified from the role of magistrate. However, judges, lawyers, and court clerks all potentially qualify as "neutral and detached," and therefore may become magistrates. The requirements that states set for becoming a magistrate vary widely, from having an attorney's license to having a high-school diploma to simply being literate.
If a search is performed pursuant to a defective warrant, any evidence obtained as a result of the search is usually suppressed. An exception to this rule arises when an officer has obtained evidence pursuant to a defective warrant that the officer relied on in "good faith" (United States v. Leon, 468 U.S. 897, 104 S. Ct. 3430, 82 L. Ed. 2d 677 ). For this exception to apply, the warrant must have been issued by a magistrate and then later ruled defective for a valid reason, and the defect must not have been the result of willful police deception. If these two requirements are satisfied, law enforcement was entitled to rely on the warrant in conducting the search, and any evidence obtained during the search is admissible against the defendant.
This exception was created to ensure that police officers would not be punished for blunders made by magistrates when issuing search warrants. Again, the primary reason courts suppress illegally obtained evidence is to deter future police misconduct. No deterrent value is served by excluding evidence obtained by an honest police officer who acted pursuant to an ostensibly valid warrant that was later ruled defective owing to an error by the magistrate.
The U.S. Supreme Court also has been asked to determine whether the way in which a search with a warrant is conducted can violate the Fourth Amendment. One troublesome area has been the question of whether police must knock on a suspect's door and announce that they have a warrant, in order to enter the premises lawfully. The general rule is that police may make a "no-knock" entry if there are reasonable grounds for such a course of action. In Richardsv. Wisconsin, 520 U.S. 385, 117 S. Ct. 1416, 137 L. Ed. 615 (1997), the U.S. Supreme Court was confronted with a decision of the Wisconsin Supreme Court that announced a blanket exception to the knock-and-announce requirement for felony drug investigations. The high court unanimously ruled that such an exception violated the Fourth Amendment and that it undermined the ability of a reviewing court to determine whether a particular no-knock entry had been reasonable. In making this ruling, the Court rejected the idea that the violent world of narcotics traffickers justified a departure from Fourth Amendment JURISPRUDENCE.
One year later, the U.S. Supreme Court clarified the standards to which police will be held when they execute "no-knock" searches, in U.S.v. Ramirez, 523 U.S. 65, 118 S. Ct. 992, 140 L. Ed.2d 191 (1998). It held that the Fourth Amendment does not hold officers to a higher standard when a "no-knock" entry results in the destruction of property. In Ramirez,a federal district court suppressed two weapons that had been seized as evidence because the police officers had violated the Fourth Amendment and 18U.S.C.A. § 3109, which permits federal law enforcement officers to damage property in certain instances. The Court acknowledged that excessive or unnecessary destruction of property during a search could be a violation of the Fourth Amendment "even though the entry itself is lawful and the fruits of the search not subject to suppression." However, in that case, the officers' actions had been reasonable, based on an informant's information, as the officers had not wanted the suspect to seek out the weapons.
Police often justify a search and seizure by stating that the suspect consented. Again, the U.S. Supreme Court has had to determine the boundaries of consent. In U.S. v. Drayton, 536 U.S. 194, 122 S. Ct. 2105, 153 L. Ed.2d 242 (2002), the Court reviewed an Eleventh Circuit Court of Appeals decision that invalidated the pat-down search of two defendants who had been on a cross-country bus trip, even though both defendants had consented to the search. The appeals court concluded that the circumstances surrounding the search had not been sufficiently free of coercion to serve as a constitutional basis for the search. The high court reversed the decision, holding that police officers on public transportation do not need to inform each passenger that they have the right to refuse a search, pat-down, or questioning in order for the investigation to remain constitutional. It deemed the distinction between the confines of a bus and the open spaces of the street to be immaterial to the reasons why citizens choose to cooperate or not. Presumably, citizens "know that their participation enhances their own safety and the safety of those around them."
Individuals who are on PROBATION typically sign an agreement that allows police to enter their homes in order to ensure that they are complying with the terms of probation. Questions have arisen over when police may search a probationer for another crime if the person has signed a probation agreement that permits such searches. Police and government officials have argued that they may conduct a search without a warrant if they believe that the suspect has committed a new crime. Criminal defendants have argued that probation agreements that require them to submit to searches at anytime only apply to searches that have a probationary purpose rather than an investigatory purpose. The U.S. Supreme Court, in United States v. Knights, 534 U.S.112, 122 S. Ct. 587, 151 L. Ed.2d 497 (2002), declined to issue a bright-line rule on this dispute but concluded that when police have reasonable suspicion and the probation agreement authorizes searches, the search is reasonable under the Fourth Amendment. Instead, the Court applied its traditional analysis for judging whether a warrantless search was reasonable. This "totality of the circumstances" approach looks at the intrusion of individual privacy and contrasts it with "legitimate governmental interests."