International Law Defined
International law as it is used in this Guide refers specifically to public international law i.e., the set of legal rules that govern international relations between public bodies that include states (i.e. Pakistan) and international organizations (i.e. the United Nations).[1] The narrowest understanding of international law thus reflects a set of obligations between and upon states.[2] However, unlike domestic law, International law is not always binding on all states. In fact, the cornerstone of international law is consent and reciprocity. In other words, states will agree to be bound (give their voluntary consent) by certain legal obligations since other states are also assuming the same obligations on a reciprocal basis. Once this reciprocal mechanism is put in place both states then have legal rights over each other. In most cases, States can choose not to be bound by certain aspects of international law e.g. by not signing and ratifying a particular treaty. However, in those situations they cannot invoke the treaty and, therefore, will not have any rights on other states.
[1] Public International Law, European Commission available at http://ec.europa.eu/justice/glossary/publicinternational-law_en.htm.
[2] Diane Marie Amann, Benchbook on International Law, Am. Soc. of Intl. Law (2014) available at https://www.asil.org/sites/default/files/benchbook/ASIL_Benchbook_Complete.pdf.
