AP Gov Court Cases

plessy v ferguson

Definition: The Supreme Court upheld Louisiana’s law requiring separate railway cars for Black and white passengers, ruling that racial segregation was constitutional under the “separate but equal” doctrine. This decision legitimized Jim Crow laws across the South and allowed racial segregation in public facilities for decades. It was later overturned by Brown v. Board of Education (1954).
Constitutional Principle: 14th Amendment – Equal Protection Clause.

schenck v united states

Definition: a man was convicted for distributing leaflets urging resistance to the WWI draft. The Court ruled that speech presenting a “clear and present danger” (such as inciting unlawful acts during wartime) is not protected by the First Amendment.
Impact: Established limits on free speech during wartime and introduced the “clear and present danger” test.
Constitutional Principle: 1st Amendment – Free Speech.

gitlow v new york

Definition: a man was arrested for publishing socialist material calling for government overthrow and violating the [state] Criminal Anarchy law. The Court upheld his conviction but, for the first time, applied the First Amendment’s free speech protections to the states through selective incorporation under the 14th Amendment.
Impact: Began the process of applying the Bill of Rights to state governments.
Constitutional Principle: 1st Amendment, 14th Amendment – Due Process Clause.

korematsu v united states

Definition: Upheld the internment of Japanese Americans during World War II as a “military necessity” following Executive Order 9066. this man’s conviction for evading internment was upheld.
Impact: National security above civil liberty in times of war. Seen today as one of the worst civil liberties violations in U.S. history; formally denounced by later courts.
Constitutional Principle: 14th Amendment – Equal Protection; national security powers.

brown v board of edu

Definition: Overturned Plessy v. Ferguson; ruled that racial segregation in public schools is inherently unequal and violates the Equal Protection Clause of the 14th Amendment.
Impact: Ended de jure segregation in education; major victory for the Civil Rights Movement.
Constitutional Principle: 14th Amendment – Equal Protection.

mapp v ohio

Definition: Police found obscene materials in a woman’s home without a valid warrant. The Supreme Court ruled that evidence obtained through illegal searches cannot be used in state courts.
Impact: Applied the Exclusionary Rule to the states, reinforcing the 4th Amendment.
Constitutional Principle: 4th Amendment – Search and Seizure; 14th Amendment – Due Process.

baker v carr

Definition: Voters challenged Tennessee’s outdated legislative districts that gave unequal representation. The Court ruled that redistricting cases are justiciable (can be decided by courts) under the Equal Protection Clause.
Impact: Led to the “one person, one vote” principle in representation.
Constitutional Principle: 14th Amendment – Equal Protection.

engle v vitale

Definition: The Court struck down a New York law requiring a voluntary prayer in public schools, ruling it violated the Establishment Clause by promoting religion.
Impact: Reinforced separation of church and state in public schools.
Constitutional Principle: 1st Amendment – Establishment Clause.

gideon v wainwright

Definition: a man was denied an attorney in a state felony case. The Court ruled that the right to counsel is essential for a fair trial and must be provided to defendants who cannot afford one.
Impact: Required states to provide public defenders in criminal cases.
Constitutional Principle: 6th Amendment – Right to Counsel; 14th Amendment – Due Process.

griswold v connecticut

Definition: Struck down a state law banning contraceptives, ruling that the Bill of Rights implies a right to privacy of married couples through the “penumbras” of several amendments.
Impact: Laid the foundation for later privacy-based cases, including Roe v. Wade.
Constitutional Principle: 1st, 3rd, 4th, 5th, and 9th Amendments – Right to Privacy..

miranda v arizona

Definition: a man’s confession was used against him without him knowing his rights. The Court ruled that suspects must be informed of their right to remain silent and right to an attorney before interrogation.
Impact: Created the Miranda warnings now required during arrests.
Constitutional Principle: 5th Amendment – Self-Incrimination; 6th Amendment – Counsel.

tinker v des moines

Definition: Students suspended for wearing black armbands to protest the Vietnam War sued the school. The Court ruled that students do not lose their First Amendment rights at school unless their expression causes substantial disruption.
Impact: Strengthened student free speech rights; only expression that infringe on other rights or cause disruptions can be limited in schools.
Constitutional Principle: 1st Amendment – Free Speech.

new york times v united states

Definition: The government tried to block publication of the Pentagon Papers. The Court ruled that prior restraint (censorship before publication) is unconstitutional unless it causes direct harm to national security.
Impact: Expanded freedom of the press and limited government censorship.
Constitutional Principle: 1st Amendment – Free Press.

wisconsin v yoder

Definition: Amish parents refused to send their children to high school, violating state law. The Court ruled in favor of the Amish, finding that compulsory schooling violated their Free Exercise rights.
Impact: Strengthened religious freedom protections.
Constitutional Principle: 1st Amendment – Free Exercise Clause.

us v nixon

Definition: During Watergate, President Nixon claimed executive privilege to withhold tapes. The Court unanimously ruled that the president is not above the law and must comply with subpoenas.
Impact: Reinforced checks and balances; led to Nixon’s resignation.
Constitutional Principle: Separation of Powers; Rule of Law.

gregg v georgia

Definition: The Court upheld the constitutionality of the death penalty under new procedures ensuring fairness. It found that capital punishment is not cruel and unusual if applied judiciously.
Impact: Reinstated the death penalty in the U.S.
Constitutional Principle: 8th Amendment – Cruel and Unusual Punishment

new jersey v tlo

Definition: A student’s purse was searched after she was caught smoking. The Court ruled that schools only need reasonable suspicion, not probable cause, to search students.
Impact: Defined limits of student privacy at school.
Constitutional Principle: 4th Amendment – Search and Seizure

hazelwood v kuhlmeier

Definition: A principal censored articles in a student newspaper. The Court ruled that schools can restrict student speech in school-sponsored activities if the censorship is reasonably related to educational goals.
Impact: Limited student press rights.
Constitutional Principle: 1st Amendment – Free Speech.

texas v johnson

Definition: Gregory Johnson burned the U.S. flag in protest. The Court ruled that flag burning is protected symbolic speech under the First Amendment.
Impact: Reinforced broad protection for expressive conduct.
Constitutional Principle: 1st Amendment – Free Speech.

shaw v reno

Definition: North Carolina created a racially gerrymandered district to elect more Black representatives. The Court ruled that race cannot be the dominant factor in drawing voting districts, must be reasoned.
Impact: Limited racial gerrymandering under equal protection.
Constitutional Principle: 14th Amendment – Equal Protection.

us v lopez

Definition: a man was charged under a federal law banning guns in school zones. The Court ruled Congress overstepped its Commerce Clause powers because carrying a gun in a local school zone is not economic activity.
Impact: First case in decades to limit federal power under the Commerce Clause.
Constitutional Principle: Commerce Clause; Federalism

kelo v city of new london

Definition: The city seized private property for economic development. The Court ruled that this qualified as public use under the Takings Clause, even if the land was given to private developers.
Impact: Expanded government’s eminent domain power.
Constitutional Principle: 5th Amendment – Takings Claus

citizens united v fec

Definition: The Court ruled that corporations and unions have the same political speech rights as individuals, allowing them to spend unlimited money on political advertising.
Impact: Led to the creation of Super PACs and major changes in campaign finance.
Constitutional Principle: 1st Amendment – Free Speech.

mcdonald v chicago

Definition: The Court ruled that the Second Amendment right to bear arms applies to state and local governments through the 14th Amendment’s Due Process Clause.
Impact: Incorporated the Second Amendment; strengthened gun rights nationally.
Constitutional Principle: 2nd Amendment; 14th Amendment – Due Process.

obergefell v hodges

Definition: The Court ruled that same-sex couples have a constitutional right to marry, as state bans violate the Equal Protection and Due Process Clauses of the 14th Amendment.
Impact: Legalized same-sex marriage nationwide; major civil rights milestone.
Constitutional Principle: 14th Amendment – Equal Protection and Due Process.

dobbs v jackson

Definition: The Court upheld a Mississippi law banning most abortions after 15 weeks and overturned Roe v. Wade and Planned Parenthood v. Casey, ruling that the Constitution does not guarantee a right to abortion. States now have the authority to regulate or ban abortion.
Impact: Ended federal abortion protections and shifted the issue to state governments.
Constitutional Principle: 14th Amendment – Due Process Clause (right to privacy).