Nullification is the doctrine that individual states can declare federal laws unconstitutional and refuse to enforce them, a state-level check rooted in the Tenth Amendment and compact theory that directly conflicts with the Supremacy Clause of Article VI and the Supreme Court's power of judicial review.
Nullification is the argument that a state can look at a federal law, decide it's unconstitutional, and simply treat it as void inside its borders. Supporters justified it with the Tenth Amendment (powers not delegated to the national government are reserved to the states) and with compact theory, the idea that the Constitution is an agreement among states, so the states get to judge when the federal government oversteps.
The problem is that the Constitution says the opposite. The Supremacy Clause in Article VI makes the Constitution and federal laws "the supreme Law of the Land," and Marbury v. Madison gave the federal courts, not the states, the job of deciding what's constitutional. The most famous showdown came in 1832, when South Carolina, following John C. Calhoun's reasoning, declared a federal tariff null and void. Nullification lost that fight and every fight since, but for AP Gov it's the clearest example of how the balance between national and state power gets contested.
Nullification lives in Topic 1.8, Constitutional Interpretations of Federalism (Unit 1), and supports learning objective AP Gov 1.8.A, which asks you to explain how the balance of power between national and state governments has changed over time based on Supreme Court interpretations. Nullification is the extreme states' rights position on that spectrum. It's the claim that states, not the Court, get the final word. Understanding why it fails (Supremacy Clause plus judicial review) is exactly the reasoning the exam wants when it asks how the Court defines federalism. It also helps you read cases like McCulloch v. Maryland, where the Court rejected a softer version of the same idea when Maryland tried to tax the national bank.
Keep studying AP® Gov Unit 1
Compact theory (Unit 1)
Compact theory is the logic underneath nullification. If the Constitution is a deal among states, then states can judge when the deal is broken. Nullification is what happens when a state acts on that judgment.
Dual Federalism (Unit 1)
Nullification is dual federalism pushed past its limit. Dual federalism says the national and state governments each rule their own separate spheres; nullification claims states can police the boundary themselves instead of letting the Supreme Court do it.
Commerce Clause (Unit 1)
When the Court reads the Commerce Clause broadly, federal power grows and states have less room to object. Nullification was an attempt to resist that growth from outside the courts; today, states fight the same battles inside the courts by challenging how far the Commerce Clause reaches.
Democratic-Republicans (Unit 1)
Jefferson and Madison's Democratic-Republicans floated early versions of nullification in the Virginia and Kentucky Resolutions, arguing states could judge the constitutionality of the Alien and Sedition Acts. The 1832 crisis didn't invent the idea, it escalated it.
Nullification usually shows up in multiple-choice questions about federalism and constitutional interpretation, often paired with the Supremacy Clause, the Tenth Amendment, or McCulloch v. Maryland. A typical stem gives you a scenario where a state refuses to follow a federal law and asks which constitutional provision resolves the conflict (answer: the Supremacy Clause, enforced through judicial review). No released FRQ has used the term verbatim, but it fits the Concept Application FRQ pattern of explaining a federal-state conflict. Practice questions in this vein ask things like how the tension between DOMA and the Supremacy Clause illustrates the Supreme Court's role in defining federalism. Your job on the exam isn't to defend nullification; it's to explain why the Constitution rejects it and what that says about who holds final interpretive power.
Compact theory is the idea; nullification is the action. Compact theory says the Constitution is an agreement among sovereign states, which means states can judge whether the federal government has overstepped. Nullification is what a state does with that conclusion, declaring a specific federal law void within its borders. You can hold compact theory as an abstract view of the founding without ever nullifying anything, but you can't justify nullification without something like compact theory behind it. On the exam, if the question is about the nature of the Constitution, that's compact theory. If a state is refusing to enforce a federal law, that's nullification.
Nullification is the claim that a state can declare a federal law unconstitutional and refuse to enforce it within its borders.
It rests on the Tenth Amendment and compact theory, but it directly contradicts the Supremacy Clause in Article VI, which makes federal law supreme over conflicting state action.
Marbury v. Madison settled that federal courts, not states, decide what is constitutional, which is why nullification has never held up legally.
South Carolina's 1832 nullification of a federal tariff, driven by John C. Calhoun, is the classic historical example of the doctrine in action.
For AP Gov 1.8.A, nullification marks the extreme states' rights end of the federalism spectrum, and explaining why it fails shows you understand how the Supreme Court shapes the federal-state balance of power.
Nullification is the doctrine that a state can declare a federal law unconstitutional and refuse to enforce it. It's grounded in the Tenth Amendment and compact theory but conflicts with the Supremacy Clause of Article VI, which is why it appears in Topic 1.8 on constitutional interpretations of federalism.
No. The Supremacy Clause makes federal law supreme over conflicting state action, and Marbury v. Madison gave federal courts the power of judicial review. Every attempt at nullification, including South Carolina's in 1832, has failed legally.
Compact theory is the underlying idea that the Constitution is an agreement among states, so states can judge federal overreach. Nullification is the action that follows, where a state actually declares a federal law void. The theory justifies the action.
A court challenge accepts that the Supreme Court gets the final word on constitutionality; nullification rejects that and claims the state itself decides. Modern states fight federal power through litigation over things like the Commerce Clause, which works within the system nullification tried to bypass.
In 1832, South Carolina, following John C. Calhoun, declared a federal tariff null and void inside the state, and the federal government refused to back down. For AP Gov you don't need a blow-by-blow of the crisis; you need to explain why nullification contradicts the Supremacy Clause and judicial review under learning objective AP Gov 1.8.A.
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