Searches and Seizures

The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated....

Amendment IV

The Fourth Amendment is the most prolific source of constitutional litigation in American history, particularly with application to the states after its incorporation through the Due Process Clause of the Fourteenth Amendment. Mapp v. Ohio (1961). Its reach is indescribably broad: every one of the millions of arrests made annually is a Fourth Amendment event. So too is every search of every person or private area by a public official, whether a police officer, schoolteacher, probation officer, airport security agent, or corner crossing guard. The Fourth Amendment is the constitutional sentry whenever someone's privacy is diminished by a governmental search or seizure. It protects a person's "legitimate expectation of privacy." Katz v. United States (1967). "Legitimate," the Court declares, means an actual expectation of privacy that society is prepared to recognize as "reasonable." In defining that phrase, the reasonableness clause of the Fourth Amendment has spawned a vast amount of litigation.

The Founders' interest in protecting Americans against unreasonable searches and seizures (and in requiring particularized warrants, as the subsequent Warrant Clause of the Fourth Amendment mandates) arises out of a trio of famous eighteenth-century cases, two from England and one from the colonies. The English cases, Entick v. Carrington (1765) and Wilkes v. Wood (1763), involved pamphleteers who were critics of the government. Both were arrested and all their books and papers seized (and, in Wilkes's case, all the papers of forty-nine of his friends) using warrants that named neither the suspects nor the places to be searched. Both defendants sued the seizing agents for trespass and won judgments in their favor.

In the case with which the Framers of the Constitution would have been most familiar, James Otis defended several colonial smugglers against seizures made through the use of "writs of assistance," which permitted the customs agents to search any place in which smuggled goods might be concealed, even if there was no particular suspicion the goods were there. Though Otis lost the case, no less an authority than John Adams saw the dispute as the spark of the American Revolution: "Then and there was the child ‘Independence' born."

The Searches and Seizures Clause may have independent meaning from that of the Warrant Clause. When Congress first considered the Bill of Rights, the text had no mention of "reasonableness." Representative Elbridge Gerry of Massachusetts said that he "presumed there was a mistake in the wording of this clause; it ought to be ‘the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable seizures and searches.'" Thus, the Searches and Seizures Clause can be thought of as an independent prohibition on the acts of governmental agents.

On the other hand, considerable historical evidence supports a different hypothesis about original intent. Based upon their experiences with British "general warrants," the Framers outlawed such devices in the Warrant Clause. By requiring probable cause and a particular description of the place to be searched and the things to be seized, the Framers prohibited rambling intrusions and rummages into people's belongings. Because courts were in the business of issuing warrants, they would naturally take charge of enforcing this provision, gauging the adequacy of the "probable cause" alleged and the particularity described.

On this view, the first part of the Fourth Amendment—the Searches and Seizures Clause—did not authorize courts to do anything. It was a statement of political moral principle, understood by the Founders to be merely declaratory, an explanation or justification for the Warrant Clause, which followed it. On this view no broad "common law" of search and seizure was invited or envisioned by those who enacted the Fourth Amendment. "The right of the people" was a collective right of the political community, not an individual's immunity against intrusion by agents of that community.

Fourth Amendment events governed by the reasonableness rule are subject to a body of law crafted by our nation's courts, both state and federal. The result has been an enormous judicial corpus of law resting on these categorical distinctions:

1. In the criminal context, a showing of individualized probable cause is necessary. Before the police may search a place or arrest an individual, they must demonstrate to a neutral magistrate that there is probable cause that a crime has occurred or that evidence of a crime may be found in the particular location described. Any search pursuant to a warrant issued by a magistrate is deemed "reasonable." Illinois v. Gates (1983).

2. Many circumstances exist in which law enforcement may dispense with the requirement to secure a warrant, so long as their conduct is otherwise objectively reasonable. For example, they may conduct a search when exigent circumstances demand it. Mincey v. Arizona (1978). They may seize that which is in "plain view." Horton v. California (1990). And, when mere regulatory interests are implicated, a lower level of individualized suspicion is generally sufficient to permit regulatory agencies to conduct unannounced inspections of industrial sites without probable cause. Donovan v. Dewey (1981).

3. Police encounters with citizens that fall short of an actual arrest—a brief, investigative stop for questioning, for example—are permitted if the police officer has some reasonable suspicion of criminality. Terry v. Ohio (1968).

4. Occasionally, the government's need to deal with potentially dangerous or disruptive hidden conditions justifies random, suspicionless intrusions. Examples in this last category include airports, Florida v. Royer (1983), and certain public school settings, such as athlete drug testing. Vernonia School District 47J v. Acton (1995).

The primary mechanism for enforcing the Searches and Seizures Clause is the exclusionary rule: evidence seized illegally may not be used against the one whose privacy was invaded, at least where there is a criminal trial against him, and there only in the prosecutor's case-in-chief. Apart perhaps from the required Miranda warning (see the Fifth Amendment's Self-Incrimination Clause), the exclusionary rule is the most criticized Warren Court criminal justice innovation. In 1961, in the case of Mapp v. Ohio, the Court, incorporating the Fourth Amendment through the Due Process Clause of the Fourteenth Amendment, declared that exclusion was constitutionally required in all state and federal courts. Before Mapp, states were free to enforce the Fourth Amendment by means other than exclusion.

Did the Framers intend the exclusionary rule? Even the rule's most ardent supporters admit that they did not. Virtually no one doubts that, until the twentieth century, criminals did not go free, as Judge (later Justice) Benjamin N. Cardozo put it, "because the constable blundered." People v. Defore (1926). The criminal would have been convicted, and the offending constable would have been liable as a tort-feasor for trespassing upon a person's privacy without proper authority or cause.

The central argument in favor of exclusion is that it is necessary to give the Fourth Amendment real, as opposed to theoretical, meaning. If police officers were allowed to offend the Constitution with impunity (which, it is alleged, they would if a defendant could be convicted on tainted evidence), the Fourth Amendment would be a "mere form of words." This argument presupposes that illegal searches and seizures are deterred by the prospect of exclusion. If the evidence cannot be used at trial, what is the point of seizing it?

The predominant view of judges and commentators is consistent with this understanding of the deterrent effect of the exclusionary rule. The trend since the mid-1970s has been to limit the exclusionary rule to the prosecutor's case-in-chief. The reason for the limitation is that it is thought that any additional deterrent effect gained by exclusion—from the grand-jury or civil trials—is negligible, or clearly outweighed by the adverse effect upon the integrity of fact-finding proceedings.

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Gerard V. Bradley
Professor of Law
Notre Dame Law School