The hierarchy of laws in the United States ranks every legal rule in a fixed order, and when two rules conflict the higher one wins. From the top down: the U.S. Constitution, federal statutes and treaties, federal regulations, state constitutions, state statutes, state regulations, and local ordinances. Article VI of the Constitution sets the top of this ladder, declaring the Constitution, federal laws, and treaties to be “the supreme Law of the Land.”1Legal Information Institute. Article VI, U.S. Constitution Everything below has to yield to what sits above it.
The Constitution Sits at the Top
No federal statute, executive order, state law, or local ordinance survives if it contradicts the Constitution. The Supremacy Clause in Article VI expressly binds judges in every state to follow the Constitution over any conflicting state law.1Legal Information Institute. Article VI, U.S. Constitution
What makes that supremacy real is judicial review. In Marbury v. Madison (1803), Chief Justice John Marshall wrote that “a law repugnant to the Constitution is void,” and that it is the judiciary’s duty “to say what the law is.”2National Archives. Marbury v. Madison (1803) That decision gave courts the power to strike down any legislative or executive act that violates the Constitution. Without it, the ranking would be theoretical. Courts are the institution that actually enforces it.
Federal Statutes and Treaties
Directly below the Constitution sit federal statutes and treaties. Both are named in the Supremacy Clause as part of “the supreme Law of the Land.” Federal statutes are laws passed by both chambers of Congress and signed by the President, and they apply nationwide.
Treaties occupy roughly the same tier. A self-executing treaty operates automatically as domestic law and courts treat it as equivalent to a federal statute.3Legal Information Institute. Self-Executing and Non-Self-Executing Treaties A non-self-executing treaty needs Congress to pass implementing legislation before courts can enforce it. Until Congress acts, that kind of treaty creates international obligations but has no force in domestic courts.
When a federal statute and a self-executing treaty conflict, courts apply the “last-in-time” rule. The Supreme Court said in Whitney v. Robertson (1888) that if the two are inconsistent, “the last one in date will control the other.”4Federal Judicial Center. Foreign Treaties in the Federal Courts In practice, courts have overwhelmingly used this rule to let later statutes override earlier treaties, not the reverse.
How Federal Law Overrides State Law
When a valid federal statute conflicts with state law, the federal law wins. This is called preemption, and it comes in three main forms. Express preemption is when Congress explicitly says the statute overrides state law on a subject. Field preemption happens when Congress regulates an area so thoroughly that no room is left for the states. Conflict preemption arises when a state law directly contradicts a federal requirement, such as when a state permits something federal law forbids.
Preemption is not automatic just because a federal law touches the same subject a state law does. When a statute doesn’t clearly address the question, the Supreme Court looks for evidence of congressional intent and generally leans toward interpretations that preserve state authority.
Executive Orders
Executive orders are directives from the President that carry the force of law within the executive branch. They sit below federal statutes because their authority comes from one of two places: a statute that grants the President discretion, or the President’s own constitutional powers under Article II, most notably the duty to “take Care that the Laws be faithfully executed.”5Library of Congress. Article II Section 3, U.S. Constitution
An executive order cannot create new law. It can direct how federal agencies enforce existing law, set enforcement priorities, manage the executive branch, or exercise powers the Constitution specifically gives the President, such as pardons or military command. An order that reaches beyond those boundaries by imposing new obligations on the public without any statutory basis is vulnerable to being struck down.
The Supreme Court’s most influential framework for judging presidential power comes from Justice Jackson’s concurrence in Youngstown Sheet & Tube Co. v. Sawyer (1952). Presidential power is strongest when Congress has authorized the action, uncertain when Congress is silent, and at its weakest when the President acts against Congress’s will.6Library of Congress. Youngstown Sheet and Tube Co. v. Sawyer, 343 U.S. 579 (1952) A new President can also simply revoke or replace a predecessor’s orders, which happens routinely at transitions.
Federal Regulations
Federal agencies such as the Environmental Protection Agency and the Food and Drug Administration write the detailed rules that put broad congressional statutes into practice. The Clean Air Act, for instance, gives the EPA authority to regulate air emissions, but the specific pollutant limits on factories come from EPA regulations.7US EPA. Summary of the Clean Air Act These regulations carry the force of law and can override conflicting state rules, but only to the extent the underlying statute actually authorizes them.
The Administrative Procedure Act sets the process. An agency must publish a proposed rule, take public comments, and issue a final rule at least 30 days before it takes effect.8Office of the Law Revision Counsel. 5 USC 553 – Rule Making Rules that skip this process can be challenged in court.
Not everything an agency publishes has the force of law. Agencies frequently issue guidance documents such as memos, FAQ pages, and interpretive letters that explain how the agency reads its own rules. Guidance can signal enforcement priorities but does not bind the public and cannot be the sole basis for an enforcement action.9United States Department of Justice. Principles for Issuance and Use of Guidance Documents
Courts No Longer Defer to Agencies on Ambiguous Statutes
For 40 years, courts followed the Chevron doctrine: when a federal statute was ambiguous, judges deferred to the administering agency’s interpretation as long as it was reasonable. In June 2024, the Supreme Court overruled Chevron in Loper Bright Enterprises v. Raimondo, holding that the Administrative Procedure Act requires courts to exercise their own independent judgment about what a statute means.10Supreme Court of the United States. Loper Bright Enterprises v. Raimondo (2024) Courts can still consult agency expertise as persuasive input, but they no longer have to accept an agency’s reading just because the text is unclear. That change weakened agencies’ ability to expand their own authority through creative statutory interpretation.
State Constitutions and State Laws
Below the federal tier, each state has its own constitution, which is the highest-ranking law within that state’s borders. State constitutions structure the state government and often include protections that go further than the federal Bill of Rights. A state can grant broader free speech or stronger privacy protections than the U.S. Constitution requires; it cannot offer less.
State statutes passed by the state legislature sit below the state constitution. They cover the wide range of subjects not exclusively controlled by the federal government, including criminal law, family law, contracts, and property. A state statute that violates either the state constitution or the federal Constitution is invalid.
Marijuana is the clearest live example of a federal-state clash. Under the federal Controlled Substances Act, marijuana is classified as a Schedule I substance, the most restrictive category, which makes possession and distribution illegal under federal law.11Office of the Law Revision Counsel. 21 USC 812 – Schedules of Controlled Substances Dozens of states have legalized marijuana for medical or recreational use. In May 2024, the Department of Justice proposed rescheduling marijuana to the less restrictive Schedule III, but as of late 2025 that rulemaking remains pending before an administrative law judge.12White House. Increasing Medical Marijuana and Cannabidiol Research Until that process concludes, marijuana remains Schedule I under federal law, and the federal government retains legal authority to enforce its drug laws in states that have legalized it, even where it has largely declined to do so.
Local Ordinances
At the bottom of the hierarchy sit local ordinances, the laws enacted by city councils, county commissions, and similar bodies. Ordinances cover the everyday work of local governance: zoning, noise, building codes, parking, and public health. A local ordinance that conflicts with a state statute, a state constitution, or any federal law is invalid.
How much power a local government has depends on the state’s framework. Under Dillon’s Rule, a municipality can exercise only powers the state has expressly granted, plus what is necessarily implied. If the state hasn’t clearly authorized it, the city can’t do it. Under Home Rule, the state constitution or a statute grants municipalities a degree of self-governance on local matters without needing specific state authorization, though state law still controls where the two conflict. Many states blend the two approaches, applying Dillon’s Rule to some kinds of local governments and Home Rule to others.
Where Tribal Governments Fit
Native American tribal governments don’t slot neatly into the federal-state-local stack. The Constitution gives Congress the power to regulate commerce “with the Indian Tribes,” and since the early 1800s courts have recognized that tribes possess inherent sovereignty, including the power to govern their members and their territory.13Legal Information Institute. Commerce With Indian Tribes The federal relationship with tribal governments is government-to-government rather than hierarchical in the usual sense.14U.S. Department of the Interior. Government-to-Government Relations with Native American Tribal Governments
That sovereignty is not unlimited. Congress can limit or override tribal authority, and tribal governments generally lack criminal jurisdiction over non-members unless a federal statute grants it. States, for their part, usually cannot tax or regulate activity on tribal lands without federal consent. The practical result is a three-way relationship where federal law is supreme, tribal authority is real but bounded, and state power largely stops at the reservation border.
How Case Law Runs Alongside the Ladder
Case law doesn’t sit on a single rung. It runs alongside the whole hierarchy. When a judge interprets a statute or applies a constitutional provision to resolve a dispute, the written opinion becomes precedent, and under stare decisis courts generally follow their own prior decisions and those of higher courts within the same system.15Federal Judicial Center. Stare Decisis
The weight of a court decision depends on what it interprets and which court issued it. A Supreme Court ruling interpreting the Constitution carries constitutional-level authority: every federal and state court is bound by it, and a Supreme Court reading of the First Amendment effectively carries the same weight as the constitutional text. A decision interpreting a federal statute is authoritative on that statute’s meaning but can be undone if Congress amends the statute. A state court’s decision on state law is authoritative within that state. So the hierarchy is best understood not as a rigid stack but as a framework in which different sources of legal authority interact, with courts acting as the referees who decide which rule controls in any given conflict.