The AP United States Government and Politics exam requires students to master 15 required Supreme Court cases. These cases form the constitutional backbone of the course, illustrating the tension between liberty and order, federal and state power, and the evolving interpretation of the Bill of Rights. Mastering these precedents is not merely about memorization; it is about understanding the constitutional reasoning that shapes American law today. This guide breaks down every required case, the constitutional principle at stake, and the holding you need to know for the exam.
The Foundational Cases: Judicial Review and Federal Supremacy
Marbury v. Madison (1803)
Principle: Judicial Review This is the cornerstone of the American judicial system. William Marbury sued James Madison for failing to deliver his judicial commission. Chief Justice John Marshall ruled that while Marbury had a right to the commission, the section of the Judiciary Act of 1789 enabling him to bring the claim directly to the Supreme Court was unconstitutional. Holding: The Supreme Court established the power of judicial review—the authority to declare legislative and executive acts unconstitutional. This case cemented the judiciary as a co-equal branch capable of checking the other two.
McCulloch v. Maryland (1819)
Principle: Federal Supremacy & Implied Powers (Necessary and Proper Clause) Maryland attempted to tax the Second Bank of the United States. The state argued the Constitution did not explicitly grant Congress the power to create a national bank. Holding: The Court ruled in favor of the federal government on two grounds. First, the Necessary and Proper Clause (Article I, Section 8) grants Congress implied powers to execute its enumerated powers (creating a bank to manage fiscal operations). Second, under the Supremacy Clause, states cannot tax the federal government ("the power to tax involves the power to destroy"). This dramatically expanded federal authority Practical, not theoretical..
United States v. Lopez (1995)
Principle: Limits on the Commerce Clause / Federalism Congress passed the Gun-Free School Zones Act of 1990, banning guns near schools under the Commerce Clause. Alfonso Lopez was arrested for carrying a concealed weapon at his high school. Holding: In a 5-4 decision, the Court struck down the law. It ruled that possessing a gun in a school zone is not an economic activity that substantially affects interstate commerce. This was the first time since the New Deal that the Court limited Congress’s Commerce Clause power, signaling a shift toward new federalism and protecting state sovereignty.
The First Amendment: Speech, Press, and Religion
Schenck v. United States (1919)
Principle: Limits on Free Speech (Clear and Present Danger) Charles Schenck distributed anti-draft leaflets during WWI. He was convicted under the Espionage Act. Holding: The Court upheld the conviction. Justice Oliver Wendell Holmes established the "clear and present danger" test: speech can be restricted if it creates a clear and present danger of bringing about substantive evils Congress has a right to prevent. The famous analogy: "The most stringent protection of free speech would not protect a man in falsely shouting fire in a theatre and causing a panic."
Tinker v. Des Moines (1969)
Principle: Student Speech / Symbolic Speech Students wore black armbands to school to protest the Vietnam War. The school suspended them. Holding: The Court ruled students do not "shed their constitutional rights to freedom of speech or expression at the schoolhouse gate." School officials may only restrict student speech if it materially and substantially disrupts the educational process. This established the "Tinker Test" (substantial disruption standard) for student speech The details matter here..
New York Times Co. v. United States (1971)
Principle: Prior Restraint / Freedom of the Press The Nixon administration sought to block the New York Times and Washington Post from publishing the Pentagon Papers (classified documents on Vietnam War decision-making). Holding: The Court ruled against the government, establishing a heavy presumption against prior restraint (government censorship before publication). The government failed to meet the burden of proving publication would cause "direct, immediate, and irreparable" harm to national security.
Citizens United v. FEC (2010)
Principle: Political Speech / Campaign Finance Citizens United, a conservative non-profit, wanted to air a film critical of Hillary Clinton close to the 2008 primary, violating the Bipartisan Campaign Reform Act (BCRA). Holding: The Court ruled that corporate funding of independent political broadcasts cannot be limited under the First Amendment. Political spending is a form of protected speech. The government cannot restrict independent expenditures by corporations, unions, or associations. This decision led to the rise of Super PACs and significantly altered campaign finance landscape.
Engel v. Vitale (1962)
Principle: Establishment Clause / School Prayer New York public schools authorized a voluntary, non-denominational prayer at the start of each day. Holding: The Court ruled this violated the Establishment Clause. Government cannot compose official prayers for any group of citizens to recite as part of a religious program carried on by government. "Voluntary" does not cure the constitutional defect; the state cannot sponsor religious activity.
Wisconsin v. Yoder (1972)
Principle: Free Exercise Clause / Religious Liberty Amish parents refused to send their children to public school past the 8th grade, violating Wisconsin’s compulsory education law. They argued it violated their Free Exercise rights. Holding: The Court ruled for the Amish. The state’s interest in universal education was not compelling enough to outweigh the burden on the free exercise of religion. The Court applied strict scrutiny, finding the Amish way of life was inseparable from their religious beliefs and that an extra two years of school would endanger their salvation/community.
The Rights of the Accused: Due Process and Incorporation
Gideon v. Wainwright (1963)
Principle: Right to Counsel / Selective Incorporation (6th Amendment) Clarence Gideon, too poor to afford a lawyer, was denied counsel in a Florida felony trial. He defended himself and was convicted. Holding: The Court unanimously ruled the 6th Amendment right to counsel is fundamental and applies to the states via the 14th Amendment Due Process Clause (Selective Incorporation). States must provide attorneys for indigent defendants in felony cases. This overturned Betts v. Brady Not complicated — just consistent..
Miranda v. Arizona (1966)
Principle: Self-Incrimination / 5th Amendment / Due Process Ernesto Miranda confessed to kidnapping and rape after hours of police interrogation without being informed of his rights. Holding: The Court ruled that custodial interrogation is inherently coercive. Prosecutors may not use statements from custodial interrogation unless the suspect was informed of their right to remain silent and right to an attorney (Miranda Rights). This is a procedural safeguard for the 5th Amendment privilege against self-incrimination.
Mapp v. Ohio (1961)
Principle: Exclusionary Rule / 4th Amendment Incorporation Police entered Dollree Mapp’s home without a valid warrant and found obscene materials. Holding: The Court applied the Exclusionary Rule to the states via the 14th Amendment. Evidence obtained in violation of the 4th Amendment (unreasonable search and seizure) cannot be used in state courts. This nationalized the remedy for illegal searches Worth keeping that in mind..
