No. A state cannot nullify federal laws. Under Article VI of the U.S. Constitution, valid federal law is the supreme law of the land, and no state legislature, governor, or state court has the authority to declare it void within the state’s borders. Every court that has considered a nullification attempt has rejected it. What states can do is refuse to lend their own police, courts, and staff to federal enforcement, and challenge federal laws they believe are unconstitutional through the federal court system.
Why Nullification Has No Legal Force
The Supremacy Clause is short and blunt. The Constitution, federal laws made under it, and U.S. treaties “shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.”1Cornell Law School. U.S. Constitution Article VI That closing phrase is the whole answer to the nullification question: state constitutions, state statutes, and state court rulings all yield when they conflict with valid federal law.
The framers wrote it that way on purpose. Under the Articles of Confederation, the national government had no reliable way to enforce its laws against defiant states, and the Constitution was designed to fix that. A federal law only claims supremacy if it was made “in Pursuance” of the Constitution, meaning Congress had the power to pass it in the first place. If it was, no state can void it.
The Supreme Court has never recognized nullification as legitimate. When Wisconsin’s Supreme Court tried to release a man held in federal custody under the Fugitive Slave Act, the U.S. Supreme Court reversed unanimously in Ableman v. Booth (1859), holding that no state court can interfere with federal proceedings or free a prisoner held under federal authority.2Justia Law. Ableman v Booth, 62 US 506 (1858) A century later, when Arkansas passed laws purporting to nullify Brown v. Board of Education, all nine justices personally signed the opinion in Cooper v. Aaron (1958) declaring that no state official “can war against the Constitution without violating his solemn oath to support it.” Constitutional rights, the Court wrote, “can neither be nullified openly and directly by state legislators or state executives or judicial officers, nor nullified indirectly by them through evasive schemes.”3Justia Supreme Court Center. Cooper v Aaron, 358 US 1 (1958)
The historical attempts confirm the point. Thomas Jefferson and James Madison drafted the Kentucky and Virginia Resolutions in 1798 against the Alien and Sedition Acts, arguing that each state could judge whether federal laws exceeded the compact’s limits.4Avalon Project. Virginia and Kentucky Resolutions No other state joined them. In 1832, South Carolina passed an Ordinance of Nullification declaring federal tariff laws unenforceable and threatening secession. President Andrew Jackson rejected the ordinance outright, Congress authorized him to use military force to collect the tariffs, and South Carolina rescinded the ordinance.5Encyclopedia Britannica. Force Bill No federal law was ever successfully voided by a state.
What States Can Do Instead
Challenge the Law in Federal Court
A state that believes a federal law exceeds Congress’s authority has a real remedy: sue. The power to decide whether a federal law is constitutional belongs to the federal judiciary, established in Marbury v. Madison (1803).6Legal Information Institute. Marbury v Madison (1803) States use this route regularly and sometimes win. The Supreme Court has struck down portions of federal laws for exceeding the commerce power, violating the Tenth Amendment, or infringing on individual rights. The difference from nullification is that a court ruling binds everyone; a state declaration binds no one.
Refuse to Help Enforce It
The federal government cannot force states to do its bidding. This is the anti-commandeering doctrine, and it is where states have real, court-tested power.
In New York v. United States (1992), the Supreme Court struck down a federal law that would have required states to take ownership of radioactive waste or regulate it on federal instructions, holding that “Congress may not simply commandeer the legislative processes of the States by directly compelling them to enact and enforce a federal regulatory program.”7Justia Supreme Court Center. New York v United States, 505 US 144 (1992) In Printz v. United States (1997), the Court extended the rule to state executive officers, striking down a Brady Act provision that required local police to run background checks on handgun buyers.8Cornell Law School. Printz v United States, 521 US 898 (1997) And in Murphy v. NCAA (2018), the Court confirmed the rule cuts both ways: Congress cannot order state legislatures to pass laws or to refrain from passing them either.9Supreme Court of the United States. Murphy v National Collegiate Athletic Association, 584 US 453 (2018)
The practical result is this: a state can tell its own police, its own courts, and its own agencies not to spend resources enforcing a federal law. What it cannot do is stop federal agents from enforcing that law using federal resources.
How This Plays Out in Practice
State Marijuana Legalization
A majority of states have legalized marijuana for medical or recreational use, but marijuana remains a controlled substance under federal law. As of early 2026, the federal government has proposed rescheduling marijuana from Schedule I to Schedule III but has not completed the process. State legalization does not make marijuana legal federally; it means the state’s own officers will not arrest people for conduct the state permits. Federal agents keep full authority to enforce the Controlled Substances Act within any state.10Office of the Law Revision Counsel. 21 USC Chapter 13, Subchapter I – Control and Enforcement
The gap has real consequences. Federal employees in legalized states can still be disciplined or fired for marijuana use, because state legalization “does not alter Federal law or Executive Branch policies regarding a drug-free workplace.”11U.S. Office of Personnel Management. Assessing the Suitability/Fitness of Applicants or Appointees on the Basis of Marijuana Use State-licensed cannabis businesses struggle to access the banking system because financial institutions face federal Bank Secrecy Act obligations when serving businesses that violate federal law.
Immigration Sanctuary Policies
Some cities and states limit how much their local agencies cooperate with federal immigration enforcement. A sanctuary jurisdiction might tell its police not to hold people solely on federal immigration detainers, or refuse to share certain information with Immigration and Customs Enforcement. These policies sit inside the anti-commandeering doctrine: the state is declining to volunteer its resources, not declaring federal immigration law void. Federal agents can still conduct enforcement operations anywhere in the country. The federal government has also tried financial leverage, attaching immigration cooperation conditions to grants like the Edward Byrne Memorial Justice Assistance Grant.12United States Department of Justice. Attorney General Sessions Announces Immigration Compliance Requirements for Edward Byrne Memorial Justice Assistance Grant Programs
Second Amendment Sanctuary Laws: The Line That Gets Crossed
Several states have passed laws declaring federal firearms regulations “invalid” or “null and void” inside the state, and some impose penalties on state officials who cooperate with federal firearms enforcement. This is where anti-commandeering ends and actual nullification begins, and federal courts have not accepted it.
A federal district court struck down Missouri’s Second Amendment Preservation Act, calling it “an unconstitutional interposition against federal law” and “an impermissible nullification attempt that violates the Supremacy Clause.” In Kansas, two men who relied on that state’s Second Amendment Protection Act to manufacture and sell unregistered firearms suppressors were prosecuted federally and convicted. The Tenth Circuit upheld the convictions, ruling that the state law was no defense to federal charges.13Justia Law. United States v Cox, No 17-3034 (10th Cir 2018) The defendants received probation partly because the sentencing judge acknowledged their own state legislature had misled them, but the convictions stood. Anyone treating a state nullification statute as a personal shield against federal prosecution is taking a gamble no court has validated.
The Money Lever
Even without commandeering, the federal government has a powerful tool: funding conditions. Congress attaches strings to federal money, and states that refuse the strings lose the money. The classic example is the drinking age. Congress did not order states to set it at 21. It directed the Secretary of Transportation to withhold 8 percent of federal highway funds from any state that lets people under 21 buy or publicly possess alcohol.14Office of the Law Revision Counsel. 23 USC 158 – National Minimum Drinking Age Every state complied. The Supreme Court upheld the approach in South Dakota v. Dole (1987), so long as the conditions relate to the federal interest and the pressure does not become outright coercion.
More recent conflicts show the same lever at higher stakes. In 2026, a federal court temporarily blocked the Trump administration from withholding roughly $10 billion in social services funding from five states over policy disagreements, covering child care, temporary assistance for families, and social services block grants. Whether or not those particular freezes survive court review, they show the reality: states depend on hundreds of billions in federal funds every year, and that dependency lets the federal government shape state behavior without sending in a single agent.
Does the Tenth Amendment Authorize Nullification?
No, and this is a common mistake. The Tenth Amendment reserves to the states or the people “powers not delegated to the United States by the Constitution, nor prohibited by it to the States.”15Library of Congress. U.S. Constitution – Tenth Amendment The amendment is real and enforceable, and it does meaningful work. It is the constitutional foundation for the anti-commandeering doctrine. It is the basis states use to win lawsuits against federal overreach.
What it does not do is make any individual state the judge of its own case against Congress. That judgment belongs to the federal courts. A state convinced Congress has exceeded its enumerated powers has a strong argument to bring to court. A state that simply declares a federal law void has produced a document with no legal effect. The anti-commandeering line of cases delivered concrete, enforceable Tenth Amendment protections for every state. Nullification, in more than two centuries of trying, has produced none.