Principle on which one court will often decline to hear a case although it has jurisdiction to do so because another court which also has jurisdiction is already seized (seised) of the matter. Although expressed as a principle of judicial politeness, the main reason for comity is avoiding dueling court decisions as well a judicial economy and avoiding duplication of effort. The basic idea is that courts should not act in a way that demeans, usurps or ousts the jurisdiction, laws, or judicial decisions of another jurisdiction or its courts.