Abstract
In an effort to render universal jurisdiction more palatable, in recent years States have applied the so-called subsidiarity principle. Under this principle, States exercising universal jurisdiction defer prosecution of international crimes to a State which has a stronger connection to the case, normally the State where the crimes were committed or the State of nationality of the accused, provided one of those States is able and willing to pursue the case. Through a study of the statutes and caselaw of States applying universal jurisdiction, this Article seeks to discern whether subsidiarity is merely a non-binding political concept, an emerging (or newly emergent) rule of customary international law, or a general principle of law applicable to all States.