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Curtis A. Bradley and Mitu Gulati’s Withdrawing from International Custom brings to mind the old joke recounted by Woody Allen in Annie Hall: “Two elderly women are at a Catskill mountain resort, and one of ’em says, ‘Boy, the food at this place is really terrible.’ The other one says, ‘Yeah, I know; and such small portions.’” Similarly, while Bradley and Gulati attack international law’s current prohibition of unilateral withdrawal from custom, they propose an alternative that differs only modestly from it (small portions). At the same time, the doctrinal change they propose would take customary international law in the wrong direction, diminishing its value to states as a mechanism to address common problems (terrible food). If the goal is, as the authors say, to strengthen rather than bury customary international law, the authors have come up with the wrong recipe.

Under the prevailing approach to withdrawal from custom, which the authors denominate the “Mandatory View,” states may exempt themselves from a rule of customary international law by persistently objecting to the rule while it is in the process of forming. Once the rule has come into being, however, states that have not persistently objected are bound until the rule dissolves through a multilateral process. Bradley and Gulati propose to replace the Mandatory View with the “Default View,” which would recognize a limited right of states to withdraw unilaterally from some rules of customary international law.

Part I of this essay considers how the Mandatory View actually differs from the authors’ proposed Default View. Section I.A examines the limitations of the Default View: some that Bradley and Gulati accept, some that they are willing to entertain and seem necessary, and some that they do not address but seem implicit in their proposal. Section I.B considers some aspects of the Mandatory View, as it actually operates, that render it less unlike the Default View than the authors suggest. Part I concludes that, taking account of the limitations of the Default View and the aspects of the Mandatory View discussed below, the doctrinal change the authors propose is less dramatic than they suggest.

Part II offers two reasons for believing that the modest doctrinal change that Bradley and Gulati propose would significantly diminish the value of customary international law as a mechanism for regulating state behavior. First, adoption of the Default View would weaken customary international law by increasing its indeterminacy and complexity. Because customary international law is unwritten and lacks a centralized mechanism of enforcement and dispute resolution, it depends to a significant degree on the clarity and simplicity of its rules for its efficacy. Customary international law already fares poorly in this respect, but the Default View would make a bad situation worse by making the applicability of its rules subject to indeterminate limitations and qualifications. If exercised, moreover, the right to unilateral withdrawal would produce an extremely complex web of relationships among the nations of the world. This added indeterminacy and complexity would weaken the norms’ pull toward compliance and in turn reduce the norms’ value to states.

Second, the Default View would reduce any given state’s incentive to comply with norms of customary international law by introducing uncertainty about how long other states will be bound by the norm. Acceptance of a norm of customary international law has value to states as a form of precommitment. Adding an option of unilateral withdrawal reduces the value of the norm to states by weakening the level of other states’ commitment. A state that acquiesces in a new norm of customary international law agrees to subordinate its own short-term interest in deviating from the norm because it believes it will benefit over the long term if other states do the same. Each state’s compliance is thus an investment that it expects to pay off over the long term. Giving states the option of unilateral withdrawal would reduce the expected long-term payoff, which in turn would make states less likely to make the investment in the first place. Thus, under the Default View, new norms of customary international law are less likely to get off the ground.

Bradley and Gulati express the hope that their proposal will prompt useful reflection about this particular feature of modern customary international law. They have clearly achieved this goal, but, for this reader, reflection has confirmed the wisdom of the prevailing view.

Publication Citation

120 Yale L.J. Online 269-291 (2011)