The Constitution prohibits the states but not the federal government—from passing any law “impairing the obligation of contracts” (Article I, section 10). “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.” —Article I, section 10, of the Constitution. [Source: The Supreme Court A to Z; Contract Clause]
Article I
contract clause
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