There can be no such thing as a political crime under the American system of
law. Since an individual has the right to hold and to propagate any ideas he
chooses (obviously including political ideas), the government may not infringe
his right; it may neither penalize nor reward him for his ideas; it may not
take any judicial cognizance whatever of his ideology.
By the same principle, the government may not give special leniency to the
perpetrator of a crime, on the grounds of the nature of his ideas.