The United States doesn't have one set of laws — it has several layers stacked on top of one another. This design is called federalism: power is split between a single national government and fifty state governments, and the states hand much of their power down again to counties, cities, and townships. A rule that shapes your day — a speed limit, a sales tax, a building code, your rights when you're arrested — could come from any one of these layers. Here's how each layer makes law, and how they all fit together.
The pyramid, top to bottom
Picture American law as a pyramid. When two rules conflict, the higher one wins — this is the principle of supremacy. A town can't pass an ordinance that violates its state's constitution, and a state can't pass a law that violates the U.S. Constitution.
- 1 The U.S. Constitution — the supreme law of the land
- 2 Federal law — treaties, acts of Congress, and agency regulations
- 3 State constitutions and state law
- 4 Local law — county and municipal ordinances
(One wrinkle: Native American tribes are a third kind of sovereign, with their own governments and law.)
1 The Constitution: the supreme law
Everything starts with the U.S. Constitution. It creates the three branches of the federal government — the legislative (Congress, which writes laws), the executive (the President, who carries them out), and the judicial (the courts, which interpret them) — and lists what the federal government is allowed to do. Just as importantly, the Bill of Rights and later amendments set limits the government can't cross. No law at any level may violate it.
2 Federal law: three ways Washington makes rules
a) Acts of Congress (statutes)
This is the process you probably learned as "how a bill becomes a law." Congress is bicameral — it has two chambers, the House of Representatives and the Senate — and a bill must clear both before it can reach the President.
- Introduction. A representative or senator introduces a bill.
- Committee. The bill goes to a committee of specialists, who hold hearings, mark it up, and amend it. Most bills quietly die here.
- Floor debate & vote. If it survives, the full chamber debates, amends, and votes. In the Senate, a filibuster can mean 60 votes are needed to move ahead.
- The other chamber. The bill must pass both the House and Senate in identical wording; a conference committee irons out differences.
- The President. He can sign it into law, veto it, or do nothing (after 10 days it becomes law anyway — unless Congress has adjourned, a "pocket veto").
- Override. Congress can overturn a veto with a two-thirds vote in both chambers.
Once signed, the law is numbered, published, and folded into the United States Code, the official compilation of permanent federal law.
Verify: Congress.gov — The Legislative Process ↗ · House.gov ↗ · USA.gov — How Laws Are Made ↗
b) Regulations (administrative law)
Congress can't spell out every detail, so it writes broad laws and delegates the fine print to executive agencies — the EPA, FDA, IRS, and dozens more. Under the Administrative Procedure Act, an agency proposes a rule in the Federal Register, opens it to public comment, then issues a final rule that is collected in the Code of Federal Regulations. These regulations carry the full force of law even though no one in Congress voted on the specifics.
c) Federal courts (case law)
When courts decide disputes, they interpret the Constitution and statutes, and their rulings become binding precedent for later cases — the doctrine of stare decisis. The Supreme Court has the final word on what federal law means. Federal courts have narrower power to "make" law than state courts do; they generally build it only around an existing constitutional provision, statute, or regulation.
Supremacy & preemption
Article VI's Supremacy Clause makes the Constitution, federal laws, and treaties the "supreme Law of the Land." When valid federal law conflicts with state law, federal law preempts (overrides) it. But there's a limit: the federal government has only the enumerated powers the Constitution grants it. Under the Tenth Amendment, everything else is reserved to the states — which is why so much of everyday law is made closer to home.
3 State law: where most law actually lives
Each state is its own sovereign, and each mirrors the federal design: a state constitution, a legislature (bicameral in every state except Nebraska, which is unicameral), a governor and state agencies, and a system of state courts. A bill becomes a state law much the way it does in Congress — introduced, sent to committee, passed by both chambers, then signed or vetoed by the governor.
States hold plenary power over everything the federal government hasn't taken: contracts, property, family law, most crimes, traffic, schools, professional licensing, and more. The scale tells the story — state courts handle roughly 83 million cases a year, while federal courts handle around 350,000. States can also grant their residents more rights than the U.S. Constitution requires; they just can't offer fewer.
Verify: USA.gov — State Governments ↗
4 Local law: counties, cities & townships
Local governments are not independent sovereigns — they are creations of the state, and the state decides how much power they get. Two competing doctrines settle that question:
- Dillon's Rule. A local government may do only what the state has expressly allowed. This is the stricter, default approach in many states.
- Home Rule. The state grants a locality a charter with broad self-governing power, so it can act on local matters unless the state forbids it.
Local laws are usually called ordinances — think zoning, noise rules, parking, business licenses, property-tax rates, and building codes. They're passed by an elected body (a county board or commission, a city council, or a township board of trustees), typically through one or more public readings, a hearing where residents can speak, and a majority vote — often with a mayor's signature.
Townships add one more layer in parts of the Northeast and Midwest, handling things like local roads, snow removal, and zoning beneath the county. New England takes it furthest: the town meeting is a form of direct democracy where residents themselves vote on the town budget and ordinances.
Verify: USA.gov — Local Governments ↗
The bottom line
The higher up the pyramid you go, the broader and rarer the law; the lower you go, the more it touches your actual street. Most of the law you feel day to day — your lease, your speed limit, your school district, your trash pickup — is written not in Washington but in your statehouse and your town hall.
And every layer answers to the people. Americans don't just live under these laws — they shape them, above all through the ballot box. Voters choose the representatives, senators, governors, state legislators, and city-council members who actually write the law, and they vote them out when they disappoint. (You can register to vote at vote.gov.)
Between elections there are quieter levers, too: contacting your representatives, testifying at a committee or city-council hearing, submitting a public comment on a proposed federal regulation, serving on a jury, or — in many states — voting directly on a ballot initiative or referendum. New England's town meetings go furthest of all, letting residents vote on local laws and budgets themselves. The law, in other words, is downstream of who shows up.