How do States React to Advisory Opinions? Rejection, Implementation, and what Lies in Between

Abstract

Advisory opinions of the International Court of Justice (ICJ) are non-binding and lack operative clauses requiring compliance. At the same time, they reflect the ICJ's views as to rights and obligations of states under international law. In that sense they are not different from binding judgments and generate expectations of implementation of the Court's determinations. Although some states may reject an opinion, others have pursued implementation through the requesting organ, or through alternative political and legal means. And although it is not always easy to ascertain the effect of an opinion on states’ behavior, advisory opinions often have practical ramifications, even if they are not implemented.