Vienna Convention on the Law of Treaties 1969

Abstract

The Convention clearly marked the beginning of a new era in the law of treaties. This book is necessarily devoted largely to the Vienna Convention on the Law of Treaties 1969 (‘the Convention’), which contains the body of rules that determine whether an instrument (document) is a treaty, how it is made, brought into force, amended, terminated and operates generally. It is not so concerned with the substance of a treaty (the rights and obligations created by it), which is known as ‘treaty law’. That is a matter for the negotiating states. For good reason, the Convention has been called ‘the treaty on treaties’. Although the Convention does not occupy the whole ground, it covers the most important areas, and is the starting point for any description of the modern law and practice of treaties. Thus, it merits its own chapter. This chapter's other purpose is to define the scope of this book by mentioning briefly those aspects of the law of treaties that the Convention does not deal with. Similarly, the MOU (which is not mentioned explicitly in the Convention) is between two or more states and looks at first sight rather like a treaty, but is not a treaty because it is not governed by international law, or, for that matter, any law (see Chapter 3 below). The UN General Assembly established the International Law Commission (ILC) in 1947 with the object of promoting the progressive development of international law and its codification. The law of treaties was one of the topics selected by the ILC at its first session in 1949 as being suitable for codification. A series of eminent British international legal scholars (Brierly, Hersch Lauterpacht, Fitzmaurice and Waldock) were appointed as (successive) Special Rapporteurs. Their task (which took them some fifteen years) was to draw up a coherent account of the already well-developed customary international law on treaties. In 1966, the ILC adopted a final set of draft articles. The UN Conference on the Law of Treaties considered them in 1966, and in 1968 and 1969. It adopted the Vienna Convention on the Law of Treaties on 22 May 1969, and the Convention entered into force on 27 January 1980. By the end of 2012, it had only 112 parties out of the 193 states that are members of the United Nations today. Some of the reasons for this will be discussed below.