MARK JANIS' INTRODUCTION TO INTERNATIONAL LAW
This research paper consists of an eight-page summary of Mark W. Janis's An Introduction to International Law.
Chapter 1 The Nature of International Law
Janis traces the origins of international law, "the roots of run deep in history," to the ancient Roman belief in ius gentium, law "common to all men" (p. 1). In the 17th century, the sovereign states of Europe established "a set of mutually agreed-upon rules respecting the nature of . . . states and their fundamental rights and obligations inter se" (p. 2). In 1627 the Dutch jurist Hugo Grotius argued that certain fundamental legal principles governed the relations of those states.
International law can be divided between public international law, which governs the relations between and among states, and private international law, which governs transactions involving private parties, but these two categories overlap. It is sometimes said that there is no such thing as international law because it is not, due to the absence of any overriding international supranational power, as readily enforceable as municipal law. This is, however, untrue. Janis points out that there are a great many rules governing international conduct "that . . . are usually, for one reason or another, observed in international practice" (pp. 3-4).
The sources of international law are not to be found in domestic or municipal law but rather in: 1. international treaties; 2. customary international practice among nations; and 3. certain fundamental norms of conduct, which before the 20th century were said to be based on natural law principles. Sources 1 and 2 are based on the consent of the nations involved, source 3 less so. Evidence of customary international law is found in many places, such as the practices and declarations of states, court decisions, writings of jurists and commentators, international arbitral awards, etc.
Janis says the pr...