1. General: The topic under discussion relates to the incidence of the criminal laws of more than one state applying to the same offence, committed by the same person, and the question with which we are confronted is how—if at all—this phenomenon may be prevented, and, if it is inevitable, and if remedies are called for, what are the available remedies.
The topic falls within the orbit of international criminal law as a branch of law comprising the system of norms of domestic criminal law, which regulates matters containing a foreign element, and of international law, which regulates matters containing a criminal element. And indeed, concurrent incidence of criminal laws as aforesaid is the fruit of the regulation by norms of this nature.
In order to provide answers to the questions concerning concurrent jurisdiction as a consequence of the concurrent incidence of the criminal laws of several states, it is necessary to answer a preliminary question, i.e., is the problem of concurrent jurisdiction a procedural problem of distribution of the judicial functions amongst the courts of a number of states, or, rather, is it a fundamental, substantive problem, of which judicial competence is only the result?