/oʊˈpiniːoʊ ˈdʒʊrɪs ɛt nɛsɛˈsɪtætɪs/ – Latin phrase
Definition: sự tin chắc vào tính hợp pháp và tính thiết yếu.
A more thorough explanation: Opinio juris et necessitatis is a Latin term used in international law. It refers to the belief or opinion that a certain practice is required by law or necessity. In the context of international law, opinio juris et necessitatis is an important element in establishing the existence of a customary international law norm. It signifies that states engage in a certain practice not just out of habit or convenience, but because they believe it is required by law or necessity.
Example: The principle of opinio juris et necessitatis holds that a state’s actions are considered lawful when they are based on a genuine belief in legal obligation and necessity.