International Law Glossary

A non-binding legal opinion issued by the ICJ on questions of international law referred by authorized UN organs or agencies.

A treaty between two states or parties, as opposed to a multilateral treaty involving three or more parties.

The informal and voluntary recognition by one state of the legislative, executive, or judicial acts of another state, not based on legal obligation.

Jurisdiction accepted by states in advance as binding, typically through an optional clause declaration under Article 36(2) of the ICJ Statute.

Rules of international law derived from consistent state practice accompanied by a sense of legal obligation (opinio juris).

A temporary suspension of certain legal obligations, typically human rights provisions, during a state of emergency, subject to strict conditions.

Legal protections granted to diplomats exempting them from the jurisdiction of the host state's courts and law enforcement.

Latin for 'toward all.' Refers to obligations owed by a state to the international community as a whole.

The formal process by which one state surrenders an individual accused or convicted of a crime to another state for trial or punishment.

Four international treaties (1949) that establish standards for the humanitarian treatment of victims of armed conflict.

Acts committed with intent to destroy, in whole or in part, a national, ethnic, racial, or religious group, as defined by the 1948 Genocide Convention.

The body of law that regulates the conduct of armed conflict, seeking to protect those not participating in hostilities and restrict means of warfare.

The branch of international law governing the conditions under which states may resort to the use of force.

Peremptory norms of international law that are accepted as norms from which no derogation is permitted under any circumstances.

The branch of international law governing the conduct of parties during armed conflict, synonymous with international humanitarian law.

A treaty between three or more states, often establishing general rules or creating international organizations.

The principle prohibiting the return of refugees or asylum seekers to territories where they face threats to life or freedom.

A subjective element of customary international law meaning the belief that a practice is carried out because it is legally obligatory.

The formal act by which a state consents to be bound by a treaty after it has been signed.

A unilateral statement made by a state when signing or ratifying a treaty, purporting to exclude or modify the legal effect of certain provisions.

The inherent right of a state to use force to defend itself against an armed attack, recognized under Article 51 of the UN Charter.

The supreme authority of a state to govern itself within its territory without external interference.

The principle that states are legally accountable for internationally wrongful acts, including breaches of treaty and customary law obligations.

A formal, binding written agreement between states or international organizations governed by international law.

The principle allowing any state to prosecute individuals for the most serious international crimes regardless of where the crime was committed.