Also known as: acts of attainder · bill of attainder
Written by attorneys · grounded in primary & secondary sources — see below
A legislative act that identifies specific persons or an ascertainable group and imposes punishment on them without a judicial trial. The prohibition prevents legislatures from bypassing judicial process to target individuals for adverse treatment based on past conduct.
State A enacts a statute that names Silver Construct and its owner Sara along with two other firms and permanently bars them from bidding on state contracts. The disqualification rests solely on prior administrative investigations that ended in settlements without any judicial finding of wrongdoing. Silver Construct sues, arguing the measure functions as legislative punishment on identified parties.
Congress passes a statute naming RiverWatch Legal Collective and declaring that any firm that represented claimants against a federal dam project is barred from federal court practice for five years. The firms sue to enjoin the law, asserting that the measure singles them out and inflicts professional disqualification by legislative decree. No judicial proceeding determines their guilt or the appropriateness of the sanction.
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A coastal state enacts a statute that names shipping companies previously fined for environmental violations and bars them from state ports for ten years while canceling their existing dockage contracts. OceanBlue Shipping sues, claiming the law imposes legislative punishment on an identified group without any new adjudication. The statute applies only to the listed firms based on past conduct.
Congress enacts a statute directing the SEC to impose a fifteen percent income surcharge on owners and executives of companies named in a 1995 contamination report and to bar them from federal remediation contracts for ten years. Fair Plastics and former manager Saul appear on the list despite having no current connection to the discharges. They challenge the measure as legislative punishment imposed without individualized hearings.
A federal statute makes it a crime for members of the Communist Party to serve as officers or employees of labor unions. Union members previously affiliated with the party face prosecution solely because of their past association. They argue the law inflicts punishment on an identifiable group through legislative action rather than judicial trial.
A federal statute denies higher-education financial aid to male students aged eighteen to twenty-six who have not registered for the draft. Students who failed to register challenge the denial as punishment imposed by legislative classification without judicial process. The law applies the restriction based solely on the identified group and past failure to act.
A statute constitutes an act of attainder when it singles out an identifiable individual or group, imposes punishment, and does so without the protections of a judicial trial. Courts examine whether the law targets specific persons rather than applying neutral criteria to an open class and whether the sanction functions as legislative punishment.
Supporting sources
A statute's stated regulatory or forward-looking purpose does not prevent it from being an act of attainder when the law specifically names parties and imposes irreversible sanctions based on past conduct without judicial process. Courts focus on the combination of specificity and punitive effect rather than the label attached by the legislature.
Supporting sources
The act of attainder prohibition targets legislative selection of specific persons for punishment without trial, while the ex post facto clause bars retroactive criminalization of past lawful conduct or increases in punishment for completed acts. A statute may violate one or both depending on whether it names identifiable targets or merely changes consequences for past behavior generally.
Supporting sources
…on one person was expressed not only in this general allocation of power, but also in more specific provisions, such as the Bill of Attainder Clause, Art. I, § 9, cl. 3. As the Court recognized in United States v. Brown , 381 U. S. 437, 442 (1965), "the Bill of Attainder Clause was intended not as a narrow, technical . . .…