Bill of Attainder
Definition - What does Bill of Attainder mean?
Historically, a bill of attainder was one created through a rare legislative act that automatically imposed capital punishment on an individual or group. These bills were created in cases where the accused committed treason or similar crimes. However, the creation of such bills is no longer allowed because they deprive the accused of the right to a jury trial.
Justipedia explains Bill of Attainder
The widespread use of bills of attainder in America dates to the Revolutionary War, when they resulted in both the automatic imposition of punishments, and the confiscation of property. However, the introduction of a constitutional clause that simply states, "No Bill of Attainder or ex post facto Law will be passed" effectively changed all of that.
However, a literal interpretation of the so-called bill of attainder clause has not always been universally embraced. In the 1965 case, United States. v. Brown, the court said that the clause was really meant to reinforce the separation of powers by ensuring that the legislature did not perform "judicial function."