This webpage includes information about the amendments to the U.S. Constitution and their role in the history of the United States of America.

Carroll v. U.S. (1925) was the first decision in which the Supreme Court acknowledged an “automobile exception” to the Fourth Amendment of the U.S. Constitution. Under this exception, an officer only needs probable cause to search a vehicle, rather than a search warrant.

Supreme Court Justice Sandra Day O'Connor and a group of high school students discuss the Fourth Amendment right against unreasonable search and seizure in the context of the landmark U.S. Supreme Court case Mapp v. Ohio and the importance of the exclusionary rule, which says that evidence gathered in an illegal search cannot be used in court.

Florida v. Bostick (1991) asked the U.S. Supreme Court to determine whether consensual searches of passenger luggage aboard a bus violated the Fourth Amendment. The Court found that the location of the search was only one factor in a larger question of whether or not a person actually had the free will to decline the search.

This resource from the National Constitution Center includes an introduction, big questions, recorded class sessions, briefing documents, slide decks, and worksheets about the fourth amendment of the United States Constitutuion.

The Founders paid close attention to the rights of the accused because they realized that the government had the power both to prosecute and convict. Protections were needed to guard against the government's abuse of these powers. Understanding how the Fourth, Fifth, Sixth and Eighth Amendments operate to guarantee such protection and how they work to ensure both individual liberty and limit government is vital to maintaining free citizenship. This lesson explores these amendments and the protections they provide.

The Founders listed several rights guaranteed to the people in the first eight amendments of the Bill of Rights. They did not believe that this list was all encompassing, so they included the Ninth Amendment as a way to protect the rights of the people that were not listed in the first Eight. This lesson explores the nature of these unnamed rights and examines the arguments around who should interpret them, judges or the people.

Katz v. United States (1967) asked the Supreme Court to decide whether wiretapping a public phone booth requires a search warrant. The Court found that an average person has an expectation of privacy while making a call in a public phone booth. As a result, agents violated the Fourth Amendment when they used electronic surveillance to listen in on a suspect without a warrant.

This lesson is based on the Annenberg Classroom video âSearch and Seizure: Mapp v. Ohio,â which explores the landmark Supreme Court decision that makes state governments also responsible for protecting our Fourth Amendment right. With the exclusionary rule, this right becomes real for all of us.

In Payton v. New York (1980), the Supreme Court found that warrantless entry into a private home to make a felony arrest violated the Fourth Amendment of the U.S. Constitution. New York state statutes could not authorize officers to illegally enter a person's home.

Case background and primary source documents concerning the Supreme Court case of Pottawatomie v. Earls. Dealing with students' Fourth Amendment protections when in schools, this lesson asks students to assess the Court's evolving definition of "reasonable" searches with respect to public school students.

In 1957, Dollree Mapp stood up to police who tried to enter her home without a search warrant. Her act of defiance led to a landmark Supreme Court ruling in Mapp v. Ohio that limited police powers. This documentary explores the Fourth Amendment case in which the Court ruled that evidence illegally obtained by police is not admissible in state courts. The 1961 case redefined the rights of the accused.

In Tennessee v. Garner (1985), the Supreme Court ruled that under the Fourth Amendment, a police officer may not use deadly force against a fleeing, unarmed suspect. The fact that a suspect does not respond to commands to halt does not authorize an officer to shoot the suspect, if the officer reasonably believes that the suspect is unarmed.

Terry v. Ohio (1968) asked the United States Supreme Court to determine the legality of stop-and-frisk, a police practice in which officers would stop passersby on the street and inspect them for illegal contraband. The Supreme Court found the practice was legal under the Fourth Amendment, if the officer could show he had a "reasonable suspicion" that the suspect was armed and dangerous.

The Fourth Amendment protects people against unreasonable searches and seizures by government officials. A search can mean everything from a frisking by a police officer to a blood test to a search of an individual's home or car. A seizure occurs when the government takes control of an individual or something in his or her possession

Can Police Officers Use GPS to Track a Vehicle? In United States v. Jones (2012) the U.S. Supreme Court found that attaching a GPS tracker to a private vehicle constituted an illegal search and seizure under the Fourth Amendment of the U.S. Constitution.

The Constitutional principle of due process, which holds that government must interact with citizens according to duly-enacted laws, balances the rights of suspects with public safety. This lesson explores the protections provided by the Fourth Amendment and how the Supreme Court has interpreted it over time.