Prior to the turn of this century, political scientists historically paid little attention to international courts, which were seen as being of little or no importance in global politics. In recent decades, however, political scientists have taken up their study, driven by the empirical proliferation of international courts and by the availability of data about their behavior. The two books under review here both formulate and test rational choice models of international cooperation and institutional design in order to explain the contribution of international courts to the practice of international cooperation, as well as the limits of courts’ independence and impact (Clifford J. Carrubba and Matthew S. Gabel) and the “hidden costs” of strengthening international courts (Leslie Johns).
Both books begin theoretically with the decision by states to engage in international collaboration and to design international dispute-settlement systems, and both then proceed to theorize the subsequent behavior of member states as litigants and of courts as interpreters of the law, as well as the influence of court rulings on a variety of international outcomes, including (in Johns’s terminology) compliance, settlement, and stability. Johns begins her book with member-state decisions to cooperate and delegate powers to international courts, but focuses on the hidden or unintended costs of strong courts, assessing her claims through case studies of the International Court of Justice (ICJ) and the Dispute Settlement Body (DSB) of the World Trade Organization. Carrubba and Gabel, in turn, put forward a general model of international cooperation and adjudication, generating predictions about the strategic behavior of both states and courts, which they test with the aid of an original data set of European Court of Justice (ECJ) decisions over four decades.
Johns begins her game-theoretic analysis in Strengthening International Courts from the perspective of the member states, which reap both benefits and costs by delegating dispute-settlement functions to international courts. All else being equal, she argues, “strong” international courts, defined in terms of high levels of delegation and obligation, increase the costs of noncompliance, and thus improve states’ compliance, with international legal agreements. Along with these benefits, however, come two “hidden costs.” First, Johns argues, strong courts increase the uncertainty associated with litigation, and thus discourage negotiated settlements in favor of costly litigation. Second, because strong courts are less permissive of occasional defections, leaders facing “tough times” (i.e., a greater-than-usual incentive to defect) become more likely to withdraw from international agreements, paying the long-term costs of exit rather than the prohibitively high short-term costs of compliance with an adverse judgment. Strong courts, in short, provide the benefit of promoting compliance with international law, but they do so at the expense of discouraging negotiated settlements and undermining the stability of international agreements.
Johns argues, however, that states can minimize, if not eliminate, these hidden costs through careful institutional design, in two ways. First, states can reduce the negative impacts of strong courts by adopting more precise rules, thus minimizing uncertainty. Stronger courts, therefore, should go hand in hand with greater precision of laws. Second, institutional designers can increase the stability of a regime by linking the court (and acceptance of its jurisdiction) to a broader political institution, such as the European Union or the WTO, thus raising the cost of exit.
The author’s empirical challenge is to test her claims about the beneficial effects and hidden costs of changes in the strength of a court, while holding other factors constant. She does so by engaging in two qualitative, longitudinal case studies of the ICJ and the WTO, respectively, identifying critical moments at which the strength of each court increased or decreased, and testing for the predicted changes in compliance, settlement, and stability before and after. In her ICJ case study, Johns identifies two landmark cases that, she argues, first weakened the Court (the 1966 South West Africa decision) and then strengthened it (the turn-of-the-century rulings against the United States over the Vienna Convention on Consular Relations). (She refers to these cases as “internal” changes in the strength of a court, resulting from the court’s own jurisprudence, as opposed to “external” changes resulting from member-state recontracting.) Tracing the fallout from each of these two cases, she argues that outcomes support her hypotheses, namely, that the weakening of the Court in the 1960s resulted in decreased compliance but greater settlement and stability, while the strengthening of the Court in the 1990s promoted compliance but undermined settlement and stability. In the WTO case, Johns rightly identifies the 1995 Dispute Settlement Understanding as a dramatic strengthening of the Court, and argues that this external change helps to explain the dramatic increase in the precision of substantive rules from the GATT to the WTO.
Johns’s case studies support the plausibility of the claim that strengthening international courts may inadvertently decrease the stability of international cooperation, insofar as courts rule against states with prohibitively high compliance costs, thus prompting at least some defendants’ exit from cooperative agreements. At a time when Britain is withdrawing from the European Union due in part to objections to the ECJ, and while the United States is holding the WTO Appellate Body hostage, this association of strong courts with decreased stability rings true, and merits further study.
As the author points out, however, her theory does not explicitly model the possibility that strategic judges might rationally anticipate government responses and apply the law selectively to avoid noncompliance and exit by defendants experiencing tough times. Such strategic judges might simultaneously pursue both (selective) compliance and stability. In this sense, Carubba and Gabel’s International Courts and the Performance of International Agreements picks up where Johns leaves off, devoting substantial effort to analyzing the strategic choices of international courts in both theory and practice.
Carrubba and Gabel propose and test a general theory of international cooperation in collective-action situations, beginning with the decision by a group of states to create an international regulatory regime, the further decision to create an international court, and the types of judicial and state behavior that should result in equilibrium. Like Johns and other rational choice theorists, they argue that international courts can help promote compliance with agreements, acting as both a “fire alarm” for the identification of potential violations and as an “information clearinghouse” through which “litigants can make their arguments and third parties (particularly other governments) can weigh in on the case” (p. 24). Courts, in this model, are assumed to be strategic actors with independent preferences, seeking wider application of international rules while avoiding noncompliance with their rulings (p. 38).
Developing and analyzing this model, the authors generate a series of propositions, from which they select two for testing in the book: First, the Political Sensitivity Hypothesis predicts that a strategic court “is more likely to rule against a defendant government the more briefs are filed against the government and the fewer briefs are filed in support of it,” suggesting that judges are sensitive to the political signals generated by member governments; the Conditional Effectiveness Hypothesis, in turn, predicts that “court rulings against defendant governments are more likely to change governmental behavior the more briefs filed in support of the ruling and the fewer filed against it” (p. 47). Having formally generated these two predictions about the behavior of courts and of losing defendants, respectively, the authors devote the bulk of their book to the innovative and painstaking testing of each claim, drawing on their original database of 40 years of ECJ cases.
With respect to the Political Sensitivity Hypothesis, the authors predict that the ECJ’s rulings are likely to be influenced by third-party observations from member governments, since the latter serve as cues of states’ willingness to sanction possible noncompliance. As the authors point out, however, they cannot simply look for a correlation between member-state observations and ECJ rulings, since both of these variables may reflect merely the strength of the plaintiff’s legal case. In their highly innovative Chapter 4, therefore, Carrubba and Gabel put forward a proxy for the quality of the legal case, in the form of the Advocate General’s (AG) Opinion. In doing so, they perform the first-ever tests to determine whether Advocates General demonstrate bias in favor of their home country’s expressed views. They find an intriguing, but very small, number of cases in which the AG’s Opinion does appear to demonstrate national bias, and on the basis of this finding they proceed with appropriate caution to use AG Opinion as a proxy for the quality of the legal case. Controlling for this and for other factors, such as the position of the European Commission, the authors produce robust findings showing a strong correlation between member-state observations and Court rulings, providing the most compelling evidence to date of a strategic Court tailoring its rulings to the expressed preferences and anticipated responses of the Union’s member governments.
Finally, Carrubba and Gabel test their Conditional Effectiveness Hypothesis, seeking to determine whether ECJ rulings against defendant states result in increased imports from other EU countries. Consistent with previous work and with their own theory, they find that ECJ rulings overall do not predict subsequent intra-European trade patterns, but that ECJ rulings with support from other member governments (in the form of third-party observations) do appear to generate a sustained and statistically significant increase in imports from the rest of the Union.
Taken together, these two books demonstrate the promise of rational-choice formal theories to generate important insights into the motivations of states that create and design international courts, the strategic judges who rule on the cases before them, and the decisions by defendant states to comply or not comply with international court rulings.
