A “presumption of X” signifies that X is taken to be the case without requiring argument or evidence to support it. The burden of its rebuttal is on the challenger of the presumption.

The presumption of liberty signifies that an individual is taken to be free to perform any feasible act without having to show that there is no sufficient reason that he should not perform it. The burden of showing sufficient cause against the act (or against this particular individual performing it) is on the challenger. The latter is characteristically the political authority, or the plaintiff in juridical disputes, but may be anybody with access to public rule-making and administration. Sufficient cause may consist of an applicable rule prohibiting the act or in enough probability ...