“No Bill of Attainder or ex post facto Law shall be passed.“ Article 1, Section 9, Clause 3 US Constitution.
A Bill of Attainder is an act passed by a legislature to punish a person without a trial in court. Bills of Attainder could condemn persons or groups of people to death without a trial. Bills of Attainder also required the “corruption of blood”, which means that heirs of the person condemned to death could not inherit the estate of the condemned person. This practice would be used by a tyrannical or dictator-type of government to punish the citizens that oppose them.
The Supreme Court set guidelines to determine if a law (legislation) violates the Bill of Attainder Clause:
1. Legislation specifies the affected persons
2. Law includes the punishment
3. There is lack of a judicial trial
Ex post facto literally means “after the fact”. It means that someone is criminally punished for conduct that was lawful when it was done. If a law is passed today, it cannot be used to convict a person for an act he committed yesterday.
Per Daniel Troy, Senior Vice-President and General Counsel, GlaxoSmithKline, writing for Heritage Foundation:
“In The Federalist No. 78, Alexander Hamilton noted that “the subjecting of men to punishment for things which, when they were done, were breaches of no law” is among “the favorite and most formidable instruments of tyranny.” Thomas Jefferson noted in an 1813 letter to Isaac McPherson “the sentiment that ex post facto laws are against natural right.”
Justice Samuel Chase defined ex post facto laws as:
“1st. Every law that makes an action done before the passing of the law, and which was innocent when done, criminal; and punishes such action.
2nd. Every law that aggravates a crime, or makes it greater than it was, when committed.
3rd. Every law that changes the punishment, and inflicts a greater punishment, than the law annexed to the crime, when committed.
4th. Every law that alters the legal rules of evidence, and receives less, or different testimony, than the law required at the time of the commission of the offence, in order to convict the offender. All these, and similar laws, are manifestly unjust and oppressive.”
In addition to Article 1, Section 9, Clause 3, the Founders also prohibited the states from passing Bills of Attainder and ex post facto laws. This is found in Article 1, Section 10, Clause 1. This shows how strongly the Founders felt about the danger of these practices – that they specifically addressed these points at the federal and state levels.
With Article 1, Section 9, Clause 3, we the people deny Congress the right to punish a person without a fair trial and to declare any act a crime that was not a crime at the time the act was committed.
We the people get assurance that no one will receive punishment by a legislative act and no one can be punished for an act committed before a law was written to prevent his or her behavior.
References:
http://www.heritage.org/constitution/#!/articles/1/essays/62/bill-of-attainder
http://www.heritage.org/constitution/#!/articles/1/essays/63/ex-post-facto
Findlay, Bruce Allyn and Findlay, Esther Blair. Your Rugged Constitution. Stanford: Stanford University Press, 1950
US Constitution
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