U.S. Constitution · Article I, Section 10, Clause 1

Contracts Clause; Bill of Attainder Clause; Ex Post Facto Clause

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Also known as: Contracts Clause · Bill of Attainder Clause · Ex Post Facto Clause

This clause bars states from coining money, issuing paper money, passing bills of attainder, ex post facto laws, or laws impairing contracts, and from granting titles of nobility.

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The text

No State shall enter into any Treaty, Alliance, or Confederation; grant Letters of Marque and Reprisal; coin Money; emit Bills of Credit; make any Thing but gold and silver Coin a Tender in Payment of Debts; pass any Bill of Attainder, ex post facto Law, or Law impairing the Obligation of Contracts, or grant any Title of Nobility.

National Archives transcription (public domain; original spelling and capitalization). archives.gov

SI explainer

What it means

This clause lists things that no state government may do. A state may not make treaties or alliances, coin money, print paper money, or require creditors to accept something other than gold or silver coin as payment. A state also may not pass a bill of attainder, an ex post facto law, or a law impairing the obligation of contracts, and may not grant a title of nobility. A bill of attainder is a law in which the legislature declares a person or group guilty and punishes them without a trial in court. An ex post facto law, as the Supreme Court has interpreted the term, is a criminal law applied backward in time, such as punishing someone for an act that was legal when done or adding punishment after the fact. A law impairing the obligation of contracts is a law that breaks or weakens binding agreements, such as canceling debts or changing the terms people already agreed to. Courts still allow states to use their police power to protect public health and safety, including reasonable and temporary limits during emergencies, but states may not use that power to single people out for punishment or to undo contracts without a strong public reason. No later amendment changed these bans. Other parts of the Constitution place similar limits on Congress and add protections for fair legal process, but this clause remains a direct limit on the states.

Original meaning

The generation that wrote and ratified this clause understood it as a set of firm limits on state legislative power drawn from basic ideas of justice and the rule of law. Madison wrote in The Federalist No. 44 that these kinds of state laws violated first principles, and in the Federal Convention Madison supported barring states from interfering with private contracts because of the harm such interference had caused, even while doubting that a bare prohibition would fully secure the goal without a broader federal check on state laws. Not all delegates agreed on every ban. Luther Martin argued in The Genuine Information that states should not be totally deprived of the right to emit bills of credit, especially since the general government had not been given authority for that purpose.

“Bills of attainder, ex-post-facto laws, and laws impairing the obligation of contracts, are contrary to the first principles of the social compact, and to every principle of sound legislation.” James Madison, The Federalist No. 44 (1788-01-25)
“Mr. MADISON admitted that inconveniences might arise from such a prohibition but thought on the whole it would be overbalanced by the utility of it. He conceived however that a negative on the State laws could alone secure the effect.” James Madison, Madison's Notes of Debates in the Federal Convention, August 28, 1787 (1787-08-28)
“It was my opinion, Sir, that the States ought not to be totally deprived of the right to emit bills of credit, and that as we had not given an authority to the general government for that purpose, it was the more necessary to retain it in the States” Luther Martin, Luther Martin, The Genuine Information, published serially Dec. 1787-Feb. 1788 (on bills of credit) (1787-12-28)

How the Supreme Court has read it

Calder v. Bull, 3 U.S. 386 (1798)

The Court held that the Ex Post Facto Clauses apply only to retroactive criminal laws, not to a state legislative act affecting civil rights such as a probate dispute.
Fletcher v. Peck, 10 U.S. 87 (1810)

The Court held that a Georgia statute rescinding land grants made by a prior legislature impaired the obligation of contracts. It was among the first decisions invalidating a state law as unconstitutional.
Trustees of Dartmouth College v. Woodward, 17 U.S. 518 (1819)

The Court held that Dartmouth College's royal charter was a contract protected by the Contract Clause, so New Hampshire could not alter it without the trustees' consent.
Home Building & Loan Assn. v. Blaisdell, 290 U.S. 398 (1934)

The Court upheld a Minnesota Depression-era mortgage moratorium law as a reasonable, temporary exercise of the state's police power that did not violate the Contract Clause. Chief Justice Hughes's majority read the Clause in light of changed economic conditions, while Justice Sutherland's dissent argued that the Clause's meaning was fixed by the framers' purpose of forbidding debtor-relief laws.
Smith v. Doe, 538 U.S. 84 (2003)

The Court held that Alaska's sex offender registration law was civil and nonpunitive, so its retroactive application did not violate the Ex Post Facto Clause.

Two schools of interpretation

Originalist / textualist reading

Originalists and textualists read this provision by starting with the public meaning of its words when adopted. On this view, no State may pass a bill of attainder, meaning a legislative act that finds guilt and imposes punishment without a judicial trial; may not pass an ex post facto law, meaning a retroactive criminal law that punishes conduct that was lawful when done or increases punishment afterward; and may not pass a law impairing the obligation of contracts, meaning a law that releases parties from, or materially alters, binding private agreements. Supporters of this reading argue that the text states absolute prohibitions, that the founding history shows a deliberate choice to forbid debtor-relief laws and other retroactive state interference, and that later pressures do not change that fixed meaning.

Living-constitutionalist reading

Living-constitutionalist and pragmatist readers argue that these bans must be applied in light of present conditions and purposes. On this view, courts should ask whether a law is punishment in effect, whether a bill singles out persons for legislative penalty without trial, and whether a contract impairment is reasonable and necessary to serve an important public purpose such as protecting health, safety, or economic welfare during an emergency. Supporters point to the Court's approach of upholding temporary, reasonable exercises of state police power and of distinguishing civil regulation from criminal punishment as examples of adapting broad constitutional language to changing social and economic needs.

Open questions

How far may a state go in modifying public contracts, including public pensions and municipal debts, without impairing obligation? What test separates a civil retroactive regulation from a punitive ex post facto law? What distinguishes a forbidden bill of attainder from permissible legislation that names or burdens specific persons or entities?

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Values for America Constitution Explorer, https://www.valuesforamerica.com/constitution (text: National Archives transcription, public domain), Article I, Section 10, Clause 1, https://www.valuesforamerica.com/constitution/article-1/section-10/clause-1

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