Jurisdiction is a manifestation of state sovereignty. It has been defined as' the capacity of a state under international law to prescribe or to enforce a rule of law.'! There is, of course, a necessary distinction to be drawn between prescriptive jurisdiction and enforcement jurisdiction.'The former embraces those acts by a state, usually in legislativeform, whereby the state asserts the right to characterize conduct as delictual. Examples would be the enactment of criminal, civil, commercial codes, or regulations governing tax or currency transactions. The latter embraces acts designed to enforce the prescriptive jurisdiction, either by way of administrative action such as arrest or seizure or by way of judicial action through the courts or even administrative agencies of a state. The relationship between the two kinds of jurisdiction is reasonably clear. There can be no enforcement jurisdiction unless there is prescriptive jurisdiction; yet there may be a prescriptive jurisdiction without the possibility of an enforcement jurisdiction, as, for example, where the accused is outside the territory of the prescribing state and not amenable to extradition. Thus, jurisdiction hinges, fundamentally, on the power to prescribe and it is on this aspect of jurisdiction that this essay will concentrate.

A further distinction, common to most legal systems is that between civil and criminal jurisdiction. Assuming that international law contains rules governing the exercise of jurisdiction by states (a matter to be discussed below), the question then arises whether such rules vary according to whether the jurisdiction is civil or criminal. It is on this question that the views of writers differ. 3