When the U.S. Constitution was written in 1787, it contained few
guarantees of individual freedom and liberty. The Federalist Party argued that such guarantees were unnecessary because the Constitution
did not give the national government power to violate individual freedoms. In contrast, Anti-Federalists argued that unless individual freedoms were specifically protected in the Constitution, the government
would not be able to resist using its power to violate those freedoms.
Federalists were in favor of a federal government being more powerful
than individual state governments. In contrast, Anti-Federalists believed
that state governments should be more powerful. To convince the AntiFederalists to adopt the Constitution, the Federalists promised to adopt
a Bill of Rights to protect individual freedoms from the government.
The Fourth Amendment was the fourth of ten amendments included in the Bill of Rights, which the United States adopted in 1791.
The Fourth Amendment 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 Warrant 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.
Americans felt a need for the Fourth Amendment to protect people
from unreasonable searches and seizures by the government. In the years
leading up to the American Revolution (1775–83), Great Britain often
had issued general warrants allowing officials to search freely for violations of its colonial taxation laws. At that time, Britain’s former prime
minister William Pitt (1708–1778), wrote, “The poorest man in his cottage may bid defiance to all the force of the Crown. It may be frail—its
roof may shake—the wind may blow through it—the storm may
enter—the rain may enter—but the King of England cannot enter; all
his force dares not cross the threshold of that ruined tenement!” The Fourth Amendment has two main parts. The second part, called
the Warrant Clause, requires the government to have a specific warrant
to search a place, arrest a person, or seize evidence of a crime. A neutral
magistrate, or judge, who does not have a personal interest in the matter
must issue the warrant. The magistrate may issue the warrant only if
there is probable cause, which means a good reason to believe that a
crime has taken place that would make a search, arrest, or seizure necessary. The warrant must specifically name the place to be searched, the
person to be arrested, or the things to be seized.
The Warrant Clause is often called the “general rule” under the
Fourth Amendment, but that is misleading. Under the first clause, which
says that there should be no unreasonable searches and seizures, Congress
and the Supreme Court have created many exceptions to the warrant requirement. For instance, an officer who sees a crime does not need to get
a warrant to make an arrest and seize evidence. An officer who thinks a
crime might be in process can stop and frisk a suspect without fully
searching the person. If an officer makes a lawful arrest, he or she may
conduct a full search of the person without a warrant. Officers who enter
a home or other place with a warrant can seize any evidence of a crime
that is in plain view, even if the item is not mentioned in the warrant.
Governments can search businesses under health and safety regulations
without warrants.
The Fourth Amendment led the Supreme Court to create a controversial doctrine called the exclusionary rule. It says that when law enforcement gets evidence by violating the Fourth Amendment, it may not
use the evidence in court against the person whose rights were violated.
People who support the exclusionary rule say it is necessary to discourage law-enforcement officers from violating the Fourth Amendment on
purpose. People who oppose the rule say that it punishes society by allowing criminals to go free when law-enforcement officers make innocent mistakes that happen to violate the Fourth Amendment.
Changes in society and technology raise new issues concerning the
scope of protection under the Fourth Amendment. In the twentieth century, courts had to decide how the amendment applies to electronic wiretapping and to searches and seizures involving automobiles. With the
growth of the Internet, courts face the question of whether the amendment protects people in online chat environments and email communications.