Here is a new paper that is not directly on a tax topic, but does touch on the treaty power, which occasionally comes up in tax policy discussion and therefore may be of interest. Kristen Eichensehr, Treaty Termination and the Separation of Powers:
The President, Congress, and the courts have long disagreed about who has the power to terminate treaties. Presidents have claimed the power to terminate treaties unilaterally, while Congress and particularly the Senate have argued that because the political branches share the power to make treaties, they should also share the power to terminate them. Unilateral presidential treaty terminations have prompted lawsuits by congressmen and private parties, Senate hearings and reports, and a divided academic literature. Meanwhile, the courts have deemed treaty termination to be a nonjusticiable political question.
This article reframes the debate over treaty termination by looking to treaty formation and analogizing to the Supreme Court's precedents on the Appointments Clause and removal power. The Appointments Clause uses the same "by and with the advice and consent of the Senate" language as the Treaty Clause and is found in the same sentence of the Constitution. Proponents of presidential power have relied on the Supreme Court's Appointments Clause jurisprudence to argue that Congress cannot limit the President's termination power. This article agrees that the oft-proposed requirement of Senate consent prior to treaty termination would be unconstitutional by analogy to the Appointments Clause. However, the Appointments Clause analogy points toward a new solution to the termination debate — namely, that the Senate could impose a "for-cause" restriction on the President's termination power. In particular, this article proposes a "for-cause" limitation implemented via a reservation, understanding, or declaration at the time of a treaty's ratification.
Recognizing the constitutionality of a "for-cause" termination reservation alters the terms of the ongoing debate about the interchangeability of congressional-executive agreements and Article II treaties. Both proponents and opponents of interchangeability have noted that the President's ability to terminate Article II treaties unilaterally makes treaties unreliable as compared to congressional-executive agreements, which cannot be terminated absent action by both Congress and the President. A "for-cause" termination reservation would increase the reliability of Article II treaties and so would shift the comparative utility of congressional-executive agreements and Article II treaties.