The Fourteenth Amendment’s meaning has been shaped less by its text than by the Supreme Court cases interpreting it. Ratified in 1868, the amendment’s first section contains four clauses that have generated most of its litigation: the Citizenship Clause, the Privileges or Immunities Clause, the Due Process Clause, and the Equal Protection Clause.1National Archives. 14th Amendment to the U.S. Constitution: Civil Rights (1868)2Constitution Annotated. Fourteenth Amendment – Rights Guaranteed: Privileges and Immunities of Citizenship, Due Process, and Equal Protection The landmark Fourteenth Amendment Supreme Court cases below are the decisions that gave those clauses their working meaning, from Reconstruction-era rulings that narrowed the amendment to modern decisions on marriage, abortion, and birthright citizenship.
Cases That Shaped the Equal Protection Clause
The Equal Protection Clause requires states to treat people within their borders equally under the law. Its interpretation has changed dramatically over more than a century.
Plessy v. Ferguson (1896)
Homer Plessy was arrested for sitting in a whites-only railway car under a Louisiana segregation law. The Supreme Court ruled that racial segregation was constitutional as long as facilities for each race were equal. The decision produced the separate but equal doctrine, which sustained state-mandated Jim Crow segregation for decades.3Wex. Wex: Separate But Equal
Brown v. Board of Education (1954)
A unanimous Court overturned Plessy in the context of public schools, holding that separate educational facilities are inherently unequal. The Court found that segregating Black children generated a sense of inferiority that harmed their education, and that this violated the Equal Protection Clause.4Wex. Wex: Brown v. Board of Education (1954)5Congressional Record. Celebrating the 50th Anniversary of Brown v. Board of Education
Loving v. Virginia (1967)
Richard and Mildred Loving were sentenced to prison because their interracial marriage violated Virginia law. The Court struck the law down, ruling that the freedom to marry is a fundamental right and that laws restricting marriage based on race violate both the Equal Protection and Due Process Clauses.6Wex. Wex: Loving v. Virginia (1967)7Constitution Annotated. Constitution Annotated: Amdt14.S1.6.3.5 Marriage and Family
Regents of the University of California v. Bakke (1978)
The Court held that rigid racial quotas in university admissions were unconstitutional, but that schools could consider race as one factor among others to promote diversity.8Wex. Wex: Regents of the University of California v. Bakke (1978) The Supreme Court significantly changed this area of law in 2023 by placing strict limits on the use of race in college admissions.
Obergefell v. Hodges (2015)
The Court legalized same-sex marriage nationwide, ruling that marriage is a fundamental right that must be available to same-sex couples on the same terms as opposite-sex couples. Denying that right, the majority found, produced unequal treatment forbidden by the Constitution.9Wex. Wex: Obergefell v. Hodges
Cases That Shaped the Due Process Clause
The Due Process Clause does two distinct kinds of work. It applies most of the Bill of Rights to state governments through selective incorporation, and it protects certain fundamental liberties that are not written into the Constitution’s text.10Constitution Annotated. Constitution Annotated: Amdt14.S1.4.1 Bill of Rights and the States11Constitution Annotated. Constitution Annotated: Amdt14.S1.4.2 Selective Incorporation
Gideon v. Wainwright (1963)
Clarence Earl Gideon was charged with a crime in Florida, could not afford a lawyer, and was refused one by the state. He defended himself and was convicted. The Supreme Court ruled that the right to an attorney is fundamental, requiring every state to provide counsel to felony defendants who cannot afford their own.12Wex. Wex: Gideon v. Wainwright (1963) The case is a leading example of incorporation.
Roe v. Wade (1973)
Working from substantive due process, the Court held that the word liberty protects a right to privacy broad enough to cover a person’s choice to have an abortion, subject to state regulation as the pregnancy progressed.13Constitution Annotated. Constitution Annotated: Amdt14.S1.6.1 Substantive Due Process Generally14Wex. Wex: Roe v. Wade (1973) Roe remained the law for nearly 50 years.
Dobbs v. Jackson Women’s Health Organization (2022)
Reviewing a Mississippi law that banned most abortions after 15 weeks, the Court overruled Roe. The majority argued that the Constitution does not mention abortion and that the right is not deeply rooted in the nation’s history, returning the authority to regulate or ban abortion to the individual states.15Wex. Wex: Dobbs v. Jackson Women’s Health Organization (2022)16CRS. The Supreme Court Overrules Roe v. Wade and Planned Parenthood v. Casey
Cases That Shaped the Citizenship Clause
The Citizenship Clause was written to secure citizenship for formerly enslaved people, directly answering the 1857 Dred Scott v. Sandford ruling that Black Americans were not citizens.17Constitution Annotated. Constitution Annotated: Amdt14.S1.1.1 Citizenship and the 14th Amendment
United States v. Wong Kim Ark (1898)
Wong Kim Ark was born in San Francisco to parents who were subjects of the Emperor of China but had their permanent home in the United States. After a trip abroad, officials blocked his return under the Chinese Exclusion Act, arguing he was not a citizen. The Supreme Court ruled that anyone born in the United States and subject to its laws is a citizen at birth, with narrow exceptions for children of foreign diplomats and children of enemies during a hostile occupation of U.S. territory.18Wex. Wex: United States v. Wong Kim Ark
Because Wong Kim Ark’s parents were permanent residents rather than diplomats, he was a citizen from birth. How that rule applies across every modern immigration status remains contested in legal and political debate today.
Cases That Shaped the Privileges or Immunities Clause
Some legal scholars believe the Privileges or Immunities Clause was originally intended to protect a broad set of fundamental rights against state interference. Early court decisions cut that reading short, and most civil rights litigation now runs through the Due Process and Equal Protection Clauses instead.19Constitution Annotated. Constitution Annotated: Amdt14.S1.2.1 Slaughter-House Cases20CRS. The Privileges or Immunities Clause
The Slaughter-House Cases (1873)
A Louisiana law gave one company a monopoly on the slaughterhouse business. Independent butchers sued, arguing the law violated their privilege to practice their trade. The Supreme Court rejected the claim and drew a sharp line between the rights of national citizenship and the rights of state citizenship, holding that the clause protects only the narrow set of rights tied specifically to national citizenship.19Constitution Annotated. Constitution Annotated: Amdt14.S1.2.1 Slaughter-House Cases Examples the Court recognized include the right to travel between states and the right to seek federal protection while on the high seas.21Constitution Annotated. Constitution Annotated: Amdt14.S1.2.2 Examples of Privileges and Immunities
The ruling meant the Privileges or Immunities Clause could not carry the weight of applying the Bill of Rights to the states or protecting most civil rights. That work fell to the Due Process Clause, which is why the clause plays only a minor role in Fourteenth Amendment doctrine today.