We have a new draft paper, forthcoming in the Harvard Law Review, on how extensively the president has come to control international law for the United States, and what, if anything, should be done about it. As we explain at the end of this post, one of the central questions implicated by the paper is: Does Congress care?

Eight years ago, Oona Hathaway demonstrated the extent of Congress’s massive delegation of authority to the president to make ex ante congressional-executive agreements, which are the vast majority of agreements for the United States. Hathaway concluded, correctly in our view, that ex ante congressional-executive agreements “possess the form of congressional-executive cooperation without the true collaboration.” Building on that and related work, our paper seeks to widen the lens to bring other forms of unilateral presidential control over international law into the picture.

As we show, in recent years the president’s control over international agreements has expanded yet further, especially with the rise of so-called “Executive Agreements+” (agreements that are alleged to complement existing law but are not authorized by such law) and by consequential political commitments (like the Paris Agreement, in part, and the Iran Deal). But presidential control over international law extends much further than this. The president dominates the U.S. interpretation and termination of international agreements; its contributions to state practice and opinio juris relating to customary international law; its interpretations of customary international law; its activities, including lawmaking acts, in international organizations; and its claims to interim obligations or provisional application concerning signed but unratified treaties. Through the accumulation of these and other pathways of control, we argue, presidents (and the executive branch more generally) have come to dominate the creation, alteration, and termination of international law for the United States. And this president-made international law has significant effects on U.S. states and private actors, and can raise the hurdles to domestic lawmaking by Congress.

The president’s dominance over international law reflects a familiar pattern that characterizes the modern rise of presidential authority more generally. As the United States grew in power over two centuries, and as the world became more complex and dangerous, Congress delegated increasing authority over international law to the executive branch, which it believed possessed better information and was structurally better suited to make international law for the United States. In addition, presidents, faced with the responsibility to conduct U.S. foreign policy, interpreted Article II to allow them to assume even more control over international law, and Congress largely acquiesced.

Many aspects of the president’s control over international law—for example, ex ante congressional executive agreements and some forms of sole executive agreements—have been given effect by the courts, and the president has long asserted without controversy the authority to interpret international law for the United States in most contexts. Other elements of the president’s control—for example, consequential political commitments and the power to terminate treaties—are a regular part of presidential practice even if they are somewhat more controversial. By contrast, some elements of presidential control, most notably the power to make Executive Agreements+, are very likely unlawful under standard separation-of-powers principles that are otherwise favorable to the president. In our paper, we seek to explain these points, and to offer some guidance on the related but understudied question of when and whether Congress has implicitly authorized the president to make international agreements.

The larger and more difficult question the paper addresses is whether presidential control of international law is legitimate in Richard Fallon’s sense of “justified, appropriate, or otherwise deserving of support.” Should we be sanguine about such presidential power as currently practiced in this context? Or should we worry about it and seek to reform it—and if so, to what degree and how? Intuitions vary widely about the right answer to these questions, and the intuitions depend in many respects on information that is either contested (e.g., is the president doing a good job in exercising control over international law for the United States?) or unknown (e.g., what is the rate of unlawful presidential action related to international law?). Our major normative proposal is that Congress should insist that there be greater transparency about executive branch actions related to international law, once those actions are taken, including perhaps most notably about the asserted legal basis for concluding binding agreements without the Senate’s advice and consent.

The ultimate question the paper raises is whether Congress, which has delegated a good deal of authority over international law to the president, cares about what the president has been doing. Congress is generally aware of the practice of presidential control and occasionally complains about it and makes small interventions. But overall Congress has delegated authority (often in the distant past) and watched as the president shapes international law for the United States. Does relative congressional inaction in these contexts reflect ignorance, indifference, or resource constraints? Or is Congress generally satisfied with the performance by presidents over the years? And does Congress think the legality concerns we raise in the paper are marginal and thus not worth worrying about? We may get some answers on these questions, as Curt will be testifying next Tuesday before the Senate Foreign Relations Committee on precisely these topics.

This article originally appeared on Lawfare.