Ex Post Facto

The US constitution states that neither Congress nor the individual states may pass an ex post facto law. Ex post facto is a curious phrase, meaning something like “out of the aftermath.” But what does this mean for us? My Latin isn’t very good, to the point of being nonexistent. Regardless, let me try to explain “ex post facto.” An ex post facto law reaches back in time to change how the law applies to a person or an activity. Wikipedia provides a better explanation: “An ex post facto law … retroactively changes the legal consequences (or status) of actions that were committed, or relationships that existed, before the enactment of the law.” For example, a law retroactively increasing the sentence a criminal is already serving would be an ex post facto law. Such a law is unconstitutional, and unfair.

Interestingly, I don’t recall ever seeing a law contested because it might be an ex post facto law. Why is that? Sometimes politicians talk of adding a wealth tax on top of the income, capital gains, and estate taxes we already pay. Sometimes they would like to increase our income taxes retroactively. Would either of these scenarios create an ex post facto law controversy? Where else might the ex post facto prohibition come into play? I am not a judge or attorney, but can’t help but wonder…