How do states and others change customary international law as well as Essay

How do states and others change customary international law as well as treaties and treaty interpretation. How do law and politics affect these attempts at law - Essay Example In order to do this, it begins with an explanation of what customary international law and treaties are before proceeding to examine the role states and others play in the process of making international law. Customary international law is an unwritten body of rules that are derived from a combination of â€Å"state practice† and opinio juris (Byers 3–4). As the term implies, â€Å"state practice† refers to what governments actually do when conducting their relationship with other governments. Opinio juris, on the other hand, is a psychological belief that a particular practice carries within it the perception by states that it is obligated by international law (Joyner 12). When a new custom is first being formed, some countries may actively adhere to it while others may oppose it. This new custom will not become a customary rule of international law until it receives widespread support and there is an opinio juris that it is required under law (Nicaragua v United States of America). Nonetheless, support does not have be actively expressed; acquiescence by countries is sufficient. Hence, a country may be bound by a customary practice that becomes law by doing nothing during the formative stage of the rule. Accordingly, most countries monitor international practices carefully to avoid becoming unwittingly bound by new customary rules (Byers 4). Treaties are black letter agreements entered into bilaterally or multilaterally with the intent of creating binding rights and obligations as amongst the parties and registered with a third party (Byers 4; Joyner 11). They may be referred to as â€Å"charter†, â€Å"convention†, covenant†, etc. (Byers 4). The rules for interpreting treaties are set out in the 1969 Vienna Convention on the Law of Treaties (VCLT) (Byers 5). The actions of states and other international legal persons often cause custom and treaties to interact with each