Expressio Unius (Est) Exclusio Alterius
- International courts and tribunals, procedure — Expressio unius exclusio alterius rule — Object & purpose (treaty interpretation and) — Ordinary meaning (treaty interpretation and) — Consistent interpretation
Published under the direction of Hélène Ruiz Fabri, with the support of the Department of International Law and Dispute Resolution, under the auspices of the Max Planck Institute Luxembourg for Procedural Law.
1 Expressio unius (est) exclusio alterius (sometimes simply referred to as expressio unius) is an interpretative maxim pursuant to which the express mention of an item excludes others. In international law, expressio unius is mainly invoked in the context of treaty interpretation (Treaties, Interpretation of). Whether this maxim is a legal rule or a law of logic has been widely discussed especially in light of its non-inclusion in the customary rules on treaty interpretation codified in the 1969 Vienna Convention on the Law of Treaties (‘VCLT’) (Interpretative...