Students of the interaction between the judicial and elected branches of government typically assume that each branch can understand the other's intentions and capabilities. In classic separation-of-power models, justices do not craft opinions they know will be overridden, and Congress does not pass laws likely to be struck down or interpreted in a manner hostile to Congress's interests. In reality, the assumption of complete information is tenuous: The transmission of information between the branches is less than perfect. Members of Congress lack the capacity to perfectly anticipate future judicial decisions, and courts cannot anticipate how elected officials will respond. Hence, congressional goals are regularly thwarted by the courts, and on occasion, judicial attempts at policymaking are overruled by Congress.

In Overruled?, Jeb Barnes asks a question that students of American politics have ignored for too long: What happens when Congress adopts legislation that undoes the judiciary's interpretation of a federal statute? He explores this question from two perspectives. First, he asks how federal courts respond to congressional efforts to override previous interpretations of federal statutes. Second, he explores the character of the legislative process when Congress attempts to overturn judicial decisions.

Barnes randomly identifies 100 episodes in which Congress attempted to override a decision of the bench that involved statutory interpretation. He then compares judicial consensus (that is, the existence of agreement among all of the federal appellate and Supreme Court justices called upon to interpret the statute) before and after congressional action. He discovers that judicial consensus is significantly more likely after Congress attempts to undo a previous judicial interpretation, suggesting the courts' willingness to be overruled by Congress. Barnes also explores the openness of the decision-making process used by Congress in responding to the courts. To assess this openness, he examines whether competing interests are afforded the opportunity to testify before congressional committees during consideration of measures to overrule the courts. He concludes that the legislative process is typically quite open during such times, suggesting the receptivity of Congress to multiple interests in reviewing the work of the courts.

This book is a great example of persuasive social science research. Barnes asks innovative questions, advances our understanding of complex phenomena, and systematically marshals convincing data to test empirical conjectures. Throughout, Barnes combines both case studies and quantitative evidence to convince the reader that his conclusions are sound. When the coding process is subjective, he confirms the reliability of his judgments by relying on several colleagues to independently code the data. Rather than merely reporting the patterns he observes, he gives the reader enough information to independently assess the significance of these patterns. The result is an important book that advances our understanding of the relationship between Congress and the courts. It generates a number of hypotheses that students of American politics will have to grapple with in the years ahead. From a normative perspective, Barnes's book leaves the reader optimistic about the democratic character of the American political system. Contrary to those who fear an imperial judiciary, elected branches of government are able to keep the courts in check, overruling their interpretations of law and correcting judicial mistakes. And contrary to those who believe that narrow special interests may hijack the legislative process, Barnes suggests otherwise.

The author's analysis raises a number of questions for students of Congress and the courts. First, as Barnes recognizes, his sample of legislative efforts is drawn from a list of cases in which Congress successfully overrides a previous court decision. But if Congress fails to act if it suspects another challenge from the judiciary, conclusions about the courts' acquiescence to Congress may be premature. As he himself makes clear, his empirical tests are designed to determine the consequences when Congress successfully overrides the federal courts.

Second, Barnes's empirical tests do not distinguish between statutory decisions made by the Circuit Courts of Appeal and those made by the Supreme Court. As it turns out, the majority of the override efforts involve decisions of the lower federal bench. This pattern has implications for the author's conclusions about the rise in judicial consensus after congressional action. One possibility is that the increase in judicial consensus after such action stems from the behavior of strategic groups who “circuit shop” after Congress strikes down a decision stemming from a particular circuit. Another possibility is that judicial consensus may appear greater after congressional action if the case in question was reviewed by the Supreme Court before—but not after—congressional action. Consensus is typically greater when the panel is smaller, as on a lower appellate bench. Another possibility is that Congress has a different relationship with the federal appellate courts than with the Supreme Court. Given that decisions of the Supreme Court are not subject to further judicial review, the Supreme Court may be less deferential to Congress than are the Circuit Courts of Appeal. Although these complications are unlikely to account for the entire increase in judicial consensus before and after congressional action and may account for an insignificant amount of the increase, future empirical work based on a larger number of cases and multivariate controls should explore these alternative explanations.

Finally, future research might return to Barnes's conclusions about the openness of the legislative process, as determined by the mix of individuals testifying before Congress during override attempts. Such testimony certainly indicates who is afforded the opportunity to shape legislative measures. But it may also reflect Congress's efforts to create the appearance of openness, before it proceeds to mark up legislation ignoring the full range of views presented in congressional hearings. Additional indicators of congressional openness would bolster Barnes's intriguing findings.

Regardless of any limitations, Overruled? should become must reading for students of Congress and the courts and of the strategic interaction of the branches. Barnes has significantly advanced our understanding of the separation of powers, and in doing so, has made a persuasive case that our political system may be healthier than we typically recognize.