Eric Talbot Jensen (Brigham Young University School of Law) has posted Presidential Pronouncements of Customary International Law As an Alternative to the Senate's Advice and Consent (Brigham Young University Law Review, Vol. 2015, No. 1525, 2016) on SSRN. Here is the abstract:
The Restatement (Fourth) of Foreign Relations Law of the United States has thus far focused on the status of treaties in United States law, and has not specifically considered the topic of customary international law. While the American Law Institute undoubtedly has good reasons for its approach, there is an emerging presidential practice that should catch the attention of the drafters and encourage them to make at least a small foray into customary international law’s impact on the domestic law of the United States. This practice consists of presidents proclaiming to the international community that certain provisions of treaties that are currently before the Senate for its advice and consent have already achieved the status of customary international law and, therefore, are binding on the United States, regardless of Senate action. While it appears that the president has the constitutional authority to determine what is customary international law as part of his foreign relations power, it is less clear that he determines the domestic effect of customary international law, particularly in instances where Congress has intentionally not taken action on a specific treaty. The Restatement (Fourth) has the opportunity to clarify the domestic effect of such presidential actions.