What is national law? In general, it is the law that governs the relationship between countries and their citizens. There are a variety of reasons why a particular country’s laws are relevant in a particular context. For example, international law may be applicable to a dispute involving an investment treaty between two parties. However, international law may conflict with a fundamental national norm. In such cases, national law is the proper choice. But what are the reasons for relying on national law?

In international relations, the rule of party autonomy is a crucial consideration. But the legitimate desire of a host state to implement international obligations is equally important. The SPP tribunal sought to distill the concept of “ordre public” by defining “general validity” as the rule governing national law. However, this principle can lead to slippery slopes and is rarely a good basis for international law. Instead, courts should strive to strike a balance between the legitimate expectations of the parties and the obligations of their host state.

The application of national law depends on how the parties to a contract agree on it. Some countries recognize treaty arbitration as a form of national law. Other countries recognize treaty arbitration as a valid method of resolving disputes in international law. For example, a country may agree to apply a certain law in international trade. But a country’s constitution may require the courts to apply national law. In the latter case, treaty arbitration is the proper form of dispute resolution in a particular area.