Author: Bart Szewczyk

[Dr. Bart Szewczyk is an Associate in Law at Columbia Law] This excellent article provides an invaluable contribution to our knowledge of the original understanding of Articles 31 and 32 of the Vienna Convention of the Law of the Treaties.  Its careful attention to the factual details, articulated in an elegant narrative, provides a vivid picture of the debates and decisions in Vienna.  And its comprehensive analysis of the historical record corrects any modern misperceptions as to what the drafters of the VCLT expected as the rules applicable to treaty interpretation.  The follow-on question, as the article notes, is “whether a regular and uncontested contrary practice has arisen—not just as a matter of what interpreters say, but of what they do—sufficient to undercut that original understanding.” (at 785). Indeed, alongside the VCLT, there may exist several conventions (in the commonwealth, rather than international, sense of the term) governing interpretation for particular treaties, courts, or jurisdictions.  Such contemporary customs or practice may be as important in interpreting treaties as the rules of the VCLT.  For instance, judgments of the International Court of Justice are formally binding only between the parties to a particular case.  The ordinary meaning of the text of Article 59 of the Court’s Statute—the “decision of the Court has no binding force except between the parties and in respect of that particular case”—allows for no other interpretation.  Yet, any State would be highly remiss—and its advocates would border on malpractice—if it argued that an ICJ judgment on a specific legal question should be disregarded because it is not binding.  On the other hand, judicial decisions of other courts may be granted less weight in the ICJ, even though formally, they have equal status with ICJ judgments under Article 38(1)(d) of the ICJ Statute as “subsidiary means for the determination of rules of law.” Or take Article 27 of the U.N. Charter:
Decisions of the Security Council on all other matters shall be made by an affirmative vote of nine members including the concurring votes of the permanent members.
In the Legal Consequences for States of the Continued Presence of South Africa in Namibia (South West Africa), the ICJ held that “concurring,” notwithstanding its apparent textual clarity and travaux to the contrary, included voluntary abstentions from voting.  The Court’s interpretation was based on the “consistent[] and uniform[]” practice of the Security Council.” (para. 22).  As for the U.N. Charter so too for the VCLT, subsequent practice can inform or even transform the original interpretation of a treaty provision. The article recognizes this tension between the original understanding of the VCLT and subsequent interpretive practice of international courts.  It notes that