Foundational Law · the Constitution of the United States

How U.S. law is layered — and how the layers check each other

Four layers, three branches, one system. Each layer draws its authority from the one above it, and the courts sit across all of them.

The checks run between the layers: courts strike statutes and rules as unconstitutional (judicial review); Congress amends the Code to override a court's reading of a statute; a constitutional amendment overrides the Court itself; an agency rule is bounded by its statute. See the landmark cases →

Read the Constitution (official sources)

The structure: three branches, three Articles

Article I — Legislative (Congress)

Creates the House and Senate and grants their powers — tax and spend, borrow, regulate interstate commerce (the Commerce Clause), coin money, declare war, and make all laws “necessary and proper.” Limits Congress (no bills of attainder, no ex post facto laws) and sets how a bill becomes law: passed by both houses and presented to the President. This is where Statutory Law comes from.

Article II — Executive (the President)

Vests executive power: faithfully execute the laws, command the armed forces, make treaties (Senate advice and consent) and appoint officers/judges, and veto legislation. The agencies that issue Regulatory Law sit here — acting only within the authority a statute delegates.

Article III — Judicial (the courts)

Establishes the Supreme Court and lower federal courts and extends judicial power to “cases and controversies.” The branch that decides what the other layers mean and whether they are constitutional — the source of Case Law.

Articles IV–VII

IV: the states (full faith & credit). V: how the Constitution is amended — the one way to override the Supreme Court. VI: the Supremacy Clause. VII: ratification.

Checks and balances — the landmark cases

Each row states the case, its citation, and what the Court held, as a matter of record — no judgment on whether it is rightly decided or currently good law. Click through to the court's own words.

Courts over statutes: judicial review

Courts over the executive

Congress vs. the executive: bicameralism & presentment

The executive bounded by statute: agency deference

The other direction: overriding the Court

Checks run up too. When the Court reads a statute a way Congress dislikes, Congress can amend it (e.g. the Lilly Ledbetter Fair Pay Act overrode Ledbetter v. Goodyear, 550 U.S. 618 (2007)). When the Court reads the Constitution, only an Article V amendment can override it (the 11th overrode Chisholm v. Georgia; the 16th overrode Pollock; the 14th overrode Dred Scott).