No More International Treaty Interpretative Methods in Canada’s Statutory Interpretation: A Question of Access to Domestic Travaux Préparatoires

The paper argues that the main reason why there was once a need for domestic courts in Canada to invoke the methodology of treaty interpretation relates to the common law-based exclusionary rule on preparatory work (or travaux preparatoires). The hypothesis is that, now that this rule has been set aside, the methods of interpretation are exactly the same in the international legal order and in Canada’s domestic legal system. Hence the contemporary trend at the Supreme Court of Canada to boycott the Vienna Convention and its interpretative provisions. To set the tone for the discussion, the background issues of treaty interpretation and interlegality are preliminarily examined, as well as the legislative drafting techniques to incorporate international conventional law domestically. Then the crux of the argument concerns the evolution in the practice of Canada’s highest court, which does not use the international interpretative methodology anymore when it needs to construe domestic implementing legislation. The paper concludes that recourse to the Vienna Convention is now superfluous given the complete commonality of interpretative approaches between international law and Canadian law, with the quasi-unrestricted access to travaux preparatoires.