Treaty Reservations and the Economics of Article 21 (1) of the Vienna Convention

The study of the use of reservation in multi-lateral treaties reveals two striking phenomena: 1) the law of reservations, enshrined in Articles 19-21 of the Vienna Convention on the Law of Treaties, favors the reserving state; and 2) the number of reservations attached to international treaties is relatively low in spite of that natural advantage. The article draws on game theory to explain the states' behavior concerning reservations to international treaties and posits that Article 21 (1) of the Vienna Convention is a good place to search for an explanation. This provision establishes the concept that reservations are reciprocal: between a reserving state and a state that objects to the reservation, that provision of the treaty will not be in force. Therefore, if a state wants to exempt itself from a treaty obligation, it must be willing to let other nations escape that same burden as well. By considering different kinds of treaties in light of various game theory models, the article considers why most treaties have relatively few reservations, whereas human rights treaties present a notable, and disappointing, exception to this general rule.