Public International Law

Public international law is a worldwide legal system which regulates the conduct of states (countries) and other actors, both in their international relations and within states’ territories. It governs many areas, such as sovereignty over territory; rights and responsibilities at sea; environmental protection; human rights and the suppression of international crimes; trade and investment; the use of military force; responsibility for breaches of the law; and the settlement of disputes. This chapter introduces the main features of public international law, including its history, sources and purposes. It outlines what the law regulates, who has rights and bears obligations under it, and how it is implemented and enforced. The chapter then considers jurisprudential debates about the nature of public international law as ‘law’ and the reasons for compliance with it, and concludes with discussion of some key critical theories.