In recent years, although the national application of international law has gathered much interest, the domestic point of view on the issue has not been adequately considered. The argument defended in this article is that the domestic use of international law is, as far as Canadian judges and other domestic actors are concerned, a question of statutory interpretation, which must be addressed, rationalized, and understood within this framework. First, the author refers to the principle according to which Canadian courts are not bound by international norms, including treaty norms, which is still valid even though some judicial and doctrinal statements seem to challenge it. International law cannot be binding upon national courts because the “Westphalian” model of international relations, regulated by the “Vattelian” legal structure, postulates the existence of an international plane that is distinct and separate from the internal spheres. Hence, the requirement that international conventions be implemented through the adoption of domestic legislation. Our courts interpret and apply Canadian law and, to the extent that international treaty law is part of domestic law, it may have an influence on them, but without ever binding them. The second part, and the main contribution of the article, consists of an analytical scheme of the persuasive force of international law. The practices of treaty implementation and how it relates to parliamentary intent — showing also that passive incorporation is impossible — as well as Driedger’s modern approach to statutory interpretation, which favours recourse to international law as a contextual element in all cases over a presumption of conformity involving the preliminary and artificial requirement of ambiguity are discussed in the article. In the final analysis, it is shown that the weight of the international law argument shall be based on the degree of incorporation of treaty norms within the Canadian legal system. In this regard, there would be four types of context in which fall the categories of treaty norms. In decreasing order of persuasive authority: (1) internal-immediate context; (2) internal-extended context; (3) external-immediate context; and (4) external-extended context.