Treaty

In modern diplomatic practice, a treaty is a formal written agreement between states (though recently also designating agreements with and between international organizations), which is legally binding under international law. Treaties differ from a variety of other international agreements like declarations, memorandums of understanding, and gentlemen's agreements, which only create moral and political obligations, nonbinding commitments, or what has been branded as "soft law." The Helsinki Final Act of the Conference on Security and Cooperation in Europe (1975) is an example of an important international agreement that was deliberately drafted in a way that was legally nonbinding to the parties at the time, circulated at the United Nations but deliberately not registered with the Secretariat. In legal jargon, and as codified in the preamble as well as Article 26 of the Vienna Convention on the Law of Treaties (1969), a treaty, unlike other international agreements, comes under "the fundamental principle" of pacta sunt servanta. This Latin phrase means that "agreements must be observed," unless forced upon or concluded in bad faith. Pacta sunt servanta is a Ciceronian principle that has been selectively and problematically appropriated by modern treaty law. In De officiis (3.24), Cicero (106–43 B.C.E.) speaks extensively of ethical conduct and makes no distinction between agreements and promises (pacta et promissa) in his meditation on the matter. By contrast, international legal discourse allows for agreements that do not follow the pacta sunt servanta rule, in turn providing for diplomatic flexibility and a bypassing of ethics. This makes it possible to daily exchange agreements and promises that have shades of legality, publicly simulating commitment, but in practice retaining opt-outs and remaining legally unenforceable.