Definition
The Fourteenth Amendment to the United States Constitution, ratified in 1868, is one of the Reconstruction Amendments and among the most consequential provisions in American constitutional law. It operates directly against state governments and state actors, not private parties, and works through five distinct sections. The operative provisions most frequently encountered in legal research are in Section 1:
1. Citizenship Clause: All persons born or naturalized in the United States and subject to its jurisdiction are citizens of the United States and of the state in which they reside. This clause overturned the Supreme Court's holding in Dred Scott v. Sandford (1857) and established birthright citizenship as a constitutional baseline.
2. Privileges or Immunities Clause: No state shall make or enforce any law that abridges the privileges or immunities of citizens of the United States. Severely narrowed by the Slaughterhouse Cases (1873), this clause has played a limited doctrinal role compared to the clauses that follow it, though scholarly and judicial interest in its revival has grown.
3. Due Process Clause: No state shall deprive any person of life, liberty, or property without due process of law. This clause has two branches: procedural due process (requiring fair process before deprivation) and substantive due process (holding that certain fundamental rights are protected from government interference regardless of the procedures used). Substantive due process has been the vehicle for some of the most contested constitutional developments of the twentieth and twenty-first centuries.
4. Equal Protection Clause: No state shall deny to any person within its jurisdiction the equal protection of the laws. This clause is the constitutional foundation for antidiscrimination law, the framework of tiered scrutiny (rational basis, intermediate scrutiny, strict scrutiny), and much of modern civil rights litigation.
5. Section 5 — Enforcement Power: Congress has the power to enforce the provisions of the amendment by appropriate legislation. This grants Congress authority to act against state violations but is subject to the congruence-and-proportionality requirement established in City of Boerne v. Flores (1997).
Common Confusion
The Fourteenth Amendment is frequently conflated with the Fifth Amendment's Due Process Clause, which applies to the federal government. When a due process or equal protection claim is brought against a state actor, the Fourteenth Amendment governs. When the claim is against federal actors, the Fifth Amendment's Due Process Clause applies — and equal protection principles have been read into that clause through reverse incorporation. The source of the constitutional claim matters for both doctrine and jurisdiction; researchers should confirm whether the challenged conduct is state or federal before proceeding.
The Privileges or Immunities Clause of the Fourteenth Amendment is also frequently confused with the Privileges and Immunities Clause of Article IV, Section 2, which governs a state's treatment of citizens from other states. These are distinct provisions with distinct doctrinal histories.
Core Elements
The amendment's most litigated provisions share a common structural logic researchers should keep in mind:
State Action Requirement: Section 1 applies only to state action — government conduct or conduct sufficiently attributable to the state. Private discrimination, without more, does not trigger Fourteenth Amendment protection (though it may trigger statutory protections).
Person vs. Citizen: The Due Process and Equal Protection Clauses protect any "person," not just citizens. Non-citizens, corporations, and other legal entities may invoke these protections. The Privileges or Immunities Clause, by contrast, protects only citizens.
Tiers of Scrutiny (Equal Protection): Courts apply different levels of review depending on the classification at issue. Rational basis review applies to most economic and social legislation. Intermediate scrutiny applies to sex-based classifications and certain others. Strict scrutiny applies to race, national origin, and classifications affecting fundamental rights.
Procedural vs. Substantive Due Process: Procedural due process asks whether the government followed fair procedures before depriving someone of life, liberty, or property. Substantive due process asks whether the government had a sufficient justification to make the deprivation at all, regardless of procedure.
Why It Matters in Research
The Fourteenth Amendment is not a single doctrine but a cluster of doctrines with different histories, different tests, and different trajectories. Researchers who treat it as a monolith will misread sources.
For historical sources, the amendment's meaning was dramatically constrained in the decades following ratification. The Slaughterhouse Cases (1873) gutted the Privileges or Immunities Clause almost immediately. The Civil Rights Cases (1883) limited Congress's enforcement power. Plessy v. Ferguson (1896) allowed "separate but equal" under the Equal Protection Clause. None of this reflects the amendment's current doctrinal meaning, and early treatises and encyclopedias will reflect the narrower post-Reconstruction reading. Researchers working in pre-1954 sources should treat equal protection analysis with particular caution.
Incorporation is a major research trap. The Bill of Rights originally applied only to the federal government. Through the doctrine of selective incorporation — developed through the Fourteenth Amendment's Due Process Clause — most Bill of Rights guarantees have been applied to the states, but the process was piecemeal and unfolded over decades. Early sources discussing state-level application of free speech, search and seizure, or jury rights may reflect a pre-incorporation world that no longer exists.
Section 5 research requires attention to the shifting boundary between congressional power and judicial supremacy. The congruence-and-proportionality test has invalidated several federal statutes as exceeding Congress's enforcement authority. Researchers analyzing the validity of civil rights legislation, abrogation of state sovereign immunity, or disability rights statutes will encounter this doctrine at the center of the analysis.
The Due Process Clause's substantive dimension has been politically and jurisprudentially volatile. Rights recognized under substantive due process at one period have been reconsidered — most notably in Dobbs v. Jackson Women's Health Organization (2022). Researchers must verify the current status of any right previously grounded in substantive due process rather than assuming older authorities remain good law.
Historical Dictionary Support
Bouvier's Law Dictionary reproduces the text of Section 1 and identifies the amendment's core prohibitions: abridging privileges or immunities, depriving persons of life, liberty, or property without due process, and denying equal protection. This textual approach was standard in late nineteenth-century legal reference works. What Bouvier and contemporaneous dictionaries could not capture was the amendment's dramatic narrowing in the Slaughterhouse Cases and its subsequent reinvigoration in the mid-twentieth century. Historical legal dictionaries treat the Fourteenth Amendment as a relatively settled text rather than a living and contested framework, which means they are useful for understanding original textual meaning but offer little guidance on the doctrinal architecture that modern researchers actually navigate. Bouvier's entry predates incorporation doctrine entirely and should not be relied upon for any question involving Bill of Rights application to the states.
Jurisdictional Note
The Fourteenth Amendment is federal constitutional law and applies uniformly against all states. However, states may provide broader protections under their own constitutions, and some state courts have developed independent state constitutional doctrine that supplements or diverges from federal Fourteenth Amendment analysis. Researchers focusing on state constitutional law should check whether a state's due process or equal protection provisions have been interpreted independently.
Encyclopedia Cross-Reference
Section 5 of the Fourteenth Amendment: Congressional Enforcement Power — The Law Mind Constitutional Law Encyclopedia
Abrogation of Sovereign Immunity Under Section 5 of the Fourteenth Amendment — The Law Mind Constitutional Law Encyclopedia
Prisoners' Rights: First, Eighth, and Fourteenth Amendment Protections — The Law Mind Constitutional Law Encyclopedia