There has been a considerable amount of academic commentary on whether the Medellin v. Texas decision has put the status of a number of existing U.S. treaties into question: see, Blawgosphere Covers Medellin v. Texas from Blawg’s Blog by Bill Gratsch .
In his new article, Law(Makers) of the Land: The Doctrine of Treaty Non-Self-Execution (Harvard Law Review, forthcoming), David H. Moore (Brigham Young University Law) takes up the gauntlet in reply to Carlos Manuel Vazquez’s article Treaties as Law of the Land: The Supremacy Clause and the Judicial Enforcement of Treaties. Here is the abstract:
This essay responds to Carlos Manuel Vázquez, Treaties as Law of the Land: The Supremacy Clause and the Judicial Enforcement of Treaties, 122 Harv. L. Rev. 599 (2008). Focusing on the authority of the lawmakers of the land, rather than on treaties’ status as law of the land as Professor Vázquez does, this essay concludes that the Foster brand of nonself-execution (which assumes that a treaty may, in the absence of a clear statament, indicate that the treaty is domestically unenforceable) is supported by the Constitution, consistent with longstanding precedent, a coherent part of the non-self-execution doctrine, and endorsed by the Supreme Court’s decision in Medellín v. Texas, 128 S. Ct. 1346 (2008).
From a Canadian perspective, due to Canada’s consitutional division of powers, there is no self-execution issue. In R. v. Hape, a Canadian Charter or Rights & Freedoms case with an international law element, the majority expressly approved the doctrine of adoption qua reception of customary international law into Canadian domestic law. While the recognition of Canada’s international law commitments is laudable, it is equally confusing; insofar as the majority’s reasons conflate conflict of laws (private international law) with public international law. Clearly, Canada has entered into various multilateral and bilateral conventions or treaties (some of which create reciprocal rights and duties between state-state or investor-state, while others create or promote private rights of action). In any case, all such international instruments are implemented domestically via legislation.
However, customary international law principles, such as universal jurisdiction or jus cogens remain elusive (e.g. Bouzari v. Islamic Republic of Iran (2004), 71 O.R. (3d) 675, leave to appeal refused,  1 S.C.R. vi). The line between custom and convention is not easily drawn, as in the case of domestic versus international (or transnational) public policy.
Perhaps the following excerpt offers a glimmer of clarity:
“68 Parliament has clear constitutional authority to pass legislation governing conduct by non-Canadians outside Canada. Its ability to pass extraterritorial legislation is informed by the binding customary principles of territorial sovereign equality and non-intervention, by the comity of nations, and by the limits of international law to the extent that they are not incompatible with domestic law. By virtue of parliamentary sovereignty, it is open to Parliament to enact legislation that is inconsistent with those principles, but in so doing it would violate international law and offend the comity of nations. However, in light of the foregoing discussion of the jurisdictional principles of customary international law, the prohibition on interference with the sovereignty and domestic affairs of other states, and this Court’s jurisprudence, Canadian law can be enforced in another country only with the consent of the host state.”
Readers may also be interested in an article by Armand de Mestral and Evan Fox-Decent entitled “Implementation and Reception: The Congeniality of Canada’s Legal Order to International Law” in THE GLOBALIZED RULE OF LAW: RELATIONSHIPS BETWEEN INTERNATIONAL AND DOMESTIC LAW, Oonagh Fitzgerald, et. al. eds., Irwin Law, 2006.
Antonin I. Pribetic