Bill of Attainder

A bill of attainder is a law enacted by a legislature that imposes punishment on a named individual or an easily identifiable group without the procedural protections of a criminal trial. Historically, English Parliament used attainders to declare individuals guilty of treason or felony, often resulting in execution, forfeiture of property, and "corruption of blood" — the inability of heirs to inherit. A narrower variant, the bill of pains and penalties, imposed lesser punishments such as fines, imprisonment, or banishment.

The device was widely viewed as a tool of political vengeance. Notable English examples include the attainder of Thomas Cromwell in 1540 and that of Thomas Wentworth, Earl of Strafford, in 1641. Parliament formally abandoned the practice in the 19th century.

In the United States, the framers regarded bills of attainder as incompatible with the separation of powers and with due process. The U.S. Constitution prohibits them in two places:

• Article I, Section 9, Clause 3 bars Congress from passing any bill of attainder.
• Article I, Section 10, Clause 1 imposes the same prohibition on the states.

The U.S. Supreme Court has applied the clause in several leading cases. In Cummings v. Missouri (1867) and Ex parte Garland (1867), the Court struck down post–Civil War loyalty oaths that effectively punished former Confederates. In United States v. Lovett (1946), it invalidated a congressional rider barring named federal employees from being paid because of alleged subversive ties. In United States v. Brown (1965), the Court struck down a statute making it a crime for Communist Party members to serve as labor union officers.

For comparative researchers, the prohibition illustrates how constitutional design can wall off the legislative branch from adjudicating individual guilt — a principle echoed, though not identically framed, in many civil-law constitutions through guarantees of judicial process and the prohibition of ex post facto punishment.