Discussion

For the purposes of disciplines such as geography, politics, economics and sociology, it is appropriate to consider the world as divided into countries and, because it is of little significance in those disciplines, simply to add that some of these countries may be federated or otherwise divided into regions or provinces. The focus is on the broad cultural patterns of political allegiance that arise by virtue of citizenship and nationality, e.g. the so-called social contract is that the State, in its nontechnical sense, will defend the interests of its citizens in return for the loyalty of its citizens.

The power to make law is an aspect of sovereignty, but it does not follow that the law is the same throughout a single sovereign's territory. Differences may arise in two ways:

• as new territory is added to old, or as two countries are combined under a single sovereign (e.g. German reunification), the laws of the formerly separate units continue distinct unless and until the sovereign assimilates one into the other. Beale offers this example at § 2.2:

"...when Hawaii was annexed to the United States it remained a separate legal unit; but when Wales was conquered by England it became a part of the new legal unit, England"; and

• when new law is to be made, the sovereign may legislate for only part of the territories either because the territory has been divided into separate units, each with their own legislative bodies, or because a single legislative body limits a new law to only a portion of the territory.

Hence, the extent of territory through which a given law applies is a political rather than a legal question, more often than not, the result of historical accidents involving the division or annexation of territory, conquest and colonisation, federation and decentralisation, all of which affect the extent of territory within which a single law prevails. In the U.S., for example, the relationship between State and federal law reflects the evolving debate between local and national interests and their respective claims to be supreme.

But in these more modern times, it is highly relevant to consider the significance of separate legal systems, particularly if the application of those systems would produce different results on the same set of facts. For example, in some parts of the world, one person may acquire multiple spouses or a spouse of the same biological sex. If such a marriage is validly created in one State, should it cease to be valid if the family travel to another State on holiday? Similarly, if a company is created with certain capacities under one law, should its capacities change if it seeks to trade in another law area? Social mobility is now the norm and trade across different markets is a vital part of the world's economic system. These and many other questions can only be answered by recognising the potential conflicts between State laws, and producing formalised systems to reconcile them. The issue is where these systems should be located.

Public International Law exists to provide a framework within which the relationship between sovereign nation States can be regulated. It provides a system of contract called treaties and offers systems to resolve disputes over territorial boundaries, access to the high seas, etc. But, it is a supranational system and, as such, it has no direct effect on the municipal laws unless each nation waives its sovereignty. Hence, although the Hague Conference on Private International Law makes recommendations, it is for each State to develop its own laws to address and resolve actual conflicts of outcome (although, in the U.S., it is acknowledged that the American Law Institute has devised federal guidelines covering some aspects of the subject). These municipal law systems are termed Private International Law or Conflict of Laws, and fall into four sections:

1. jurisdiction: forum shopping can be a problem and it is necessary for litigants to demonstrate a real connection between their dispute and the court invited to adjudicate;
2. characterisation in which the court allocates the causes of action to their appropriate legal classification subject to any issues of public policy;
3. choice of law: where the result will be different depending on which law is applied, clear and consistent rules must be applied to decide which competing law(s) should be applied (including the issue of renvoi);
4. the chosen law(s) (the lex causae) should be applied: this is not straightforward because the court in one State is being asked to give extraterritorial effect to another State's laws, thereby making its own laws inapplicable (and, arguably, breaching sovereignty).