Fourth Amendment: Unreasonable Search and Seizure

National Constitution Center

As part of the National Constitution Center’s 27 Amendments (In 27 Days) project, each day we will look at a constitutional amendment. Through partnerships with leading scholars and universities, government agencies, media outlets, and more, the National Constitution Center will profile one amendment each day throughout the month of February.

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Photo via Bruce Bortin/Flickr

Photo via Bruce Bortin/Flickr

Today, we look at an amendment that is seemingly in the news daily: the Fourth Amendment, which protects people from unreasonable searches and seizures.

Full Text of the Fourth Amendment

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.


Applying to arrests and to searches of persons, homes, and other private places, this amendment requires a warrant, thereby placing a neutral magistrate between the police and the citizen. Source:  U.S. Senate


This amendment protects the people’s right to be secure in our “persons, houses, papers, and effects, against unreasonable searches and seizures” by the government. The Framers of the Constitution were especially concerned about “general warrants” which authorized broad searches of innocent citizens private papers without “particularly describing the place to be searched, and the person or things to be seized.”

Today, an unreasonable search or seizure can involve a clear violation of private property rights, like the police entering someone’s home without a warrant supported by probable cause of wrongdoing, or can be subtler, like a police officer using a thermal imaging device to reveal excessive amounts of heat being generated inside a house.


1. The Library of Congress Constitution Annotated. Contains a detailed history of the amendment, along with past and recent court cases.

2. Cornell Legal Information Institute.  Includes  information from Wex, a free legal dictionary and encyclopedia sponsored and hosted by the Legal Information Institute at the Cornell Law School. Wex entries are collaboratively created and edited by legal experts.

3. U.S. Courts website. This resource allows you to understand what Supreme Court decisions clarify reasonable search and seizure, apply the precedents, and see examples.

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