MBE Rules · Constitutional Law
Bills of Attainder and Ex Post Facto
Art. I §§9-10 — attainder/ex post facto
The rule
Legislatures may not punish named individuals without trial, nor retroactively criminalize conduct, increase punishment, or reduce the evidence required for conviction; the ex post facto bars apply only to criminal laws.
In plain English
Bills of Attainder are laws that punish specific individuals or groups without a trial, which is prohibited by the Constitution. Ex Post Facto laws make it illegal for legislatures to retroactively change the law to increase penalties or change the standards of evidence for convictions. Both rules ensure fairness in the legal process and protect individuals from arbitrary punishment.
Worked example
In 2021, a state legislature passed a law declaring that John, a specific individual, is guilty of treason and must serve ten years in prison without a trial. This law is unconstitutional as it constitutes a Bill of Attainder, and John cannot be punished without due process. Therefore, the law is invalid, and John cannot be imprisoned.
Memory hook
No trial, no punishment: Bills of Attainder and Ex Post Facto laws keep justice fair and square.
The trap
Exams may present scenarios where a law seems to retroactively affect a person's rights but does not clearly state the punishment, leading students to overlook the Bill of Attainder aspect. Students might also confuse civil penalties with criminal laws, mistakenly applying the ex post facto rule where it does not apply.
How examiners test it
Questions often involve hypothetical laws that target specific individuals or change penalties for past actions, requiring candidates to identify whether these laws violate constitutional protections against Bills of Attainder or Ex Post Facto laws.
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