A Note on Bjorge’s The Evolutionary Interpretation of Treaties

A treaty. An international court or tribunal. Two states. The search for meaning. Submissions are made by the parties as to the ‘correct’ or ‘best’ interpretation of the treaty. Recourse is had to the canons of interpretation in the Vienna Convention on the Law of Treaties. Terms like ‘good faith’, ‘ordinary meaning’, ‘object and purpose’ are repeated like incantations. So too, almost as often, terms like ‘subsequent agreement’, ‘subsequent practice’ and ‘evolutionary interpretation’ reverberate. One sometimes wonders what has happened to the actual text of the treaty to be interpreted, blanketed as it now is in interpretative theory.

In this careful and lawyerly study, Eirik Bjorge cuts through all this, drawing our attention back to basics. First and above all one has to look at the text of the treaty. The text, in its authentic language(s), is the primary expression of the common intention of the parties. This common intention is to be determined objectively by applying the canons of interpretation established in the Articles 31-33 of the Vienna Convention. Bjorge points out that the evolutionary interpretation of treaties is nothing more than that: an expression of the traditional canons of treaty construction. It is a method suited for all treaties, not just one class. It is a method for all international tribunals, not just one. But how much interpretation can the text stand? It is this question that encapsulates the quest for meaning.

Take the Navigational and Related Rights case as an example. The text in question was the Treaty of Limits, concluded between Costa Rica and Nicaragua in 1858. Lengthy submissions were made by both states as to the correct interpretation of a simple expression, ‘libre navegación … con objetos de comercio’ (ICJ Reports 2009, paras 43-71). The Court read the text as ‘for the purposes of commerce’, as Costa Rica had argued, and not ‘with objects of trade’, in Nicaragua’s contrary argument. The freedom accordingly encompassed not only the transport of goods but also the transport of people, including tourists.

If one considers evolutionary interpretation to involve bringing a treaty up to speed with modern times, then the Court engaged in such an interpretation. It considered the term ‘commerce’ as having its modern meaning, rather than the one it had during the conclusion of the Treaty of Limits. But in truth it was not necessary to engage in such an interpretation because the 1859 traveler was in evidence (the principal use of the ‘Nicaragua route’ in the mid-19^th century was for transit of persons to California). Although evolutionary interpretation was hardly necessary, the Court interpreted the text on the basis that some terms had a ‘meaning or content capable of evolving’ (para 64).

Take, by contrast, Whaling in the Antarctic. The text in question was the International Convention for the Regulation of Whaling 1946, Article VIII, which permitted nationals of states parties to obtain a permit authorizing them to ‘kill, take and treat whales for purposes of scientific research’ (ICJ Reports 2014, para 43). The expression ‘scientific research’ was intensely disputed. The Court referred to the Convention as ‘an evolving instrument’ (para 45), but it did not seem to engage in an evolutionary interpretation. It accepted that the term scientific research could include ‘lethal methods’, but it rejected the criterion (which the parties had accepted) that lethal methods ‘must avoid an adverse effect on the relevant stocks’ (para 85). In a case where an evolutionary interpretation might have seemed called for to bring the Convention in line with modern understandings of the preservation of whale stocks, the Court insistently did not ‘devise any alternative’ criteria (para 86): it decided the case on the facts as put in evidence. We seem to have a Court that is evolutionary when it is not really necessary but not evolutionary when the text invites such an interpretation.

For his part, Bjorge has grasped the heart of the Vienna Convention. With the object and purpose of the treaty of treaties in mind – determining the true intention of the parties – he incisively analyses an array of cases from a series of international tribunals. Given a solid grounding in the Vienna Convention, Bjorge reveals as clear and unitary what others with their categories have struggled to understand.

Editor’s note: this post is adapted from Professor Crawford’s Foreword to Eirik Bjorge’s book.