"It is heresy in some circles to suggest that the Supreme Court could learn anything useful from the world outside our borders. This book argues that the European doctrine of proportionality not only helps us understand our existing constitutional rules more clearly but also leads to some significant improvements. Readers will find much to learn about our own constitutional system as well as European law. As the authors show, we need to take seriously the idea of proportionality between the ends and means of government action."--Daniel Farber, Sho Sato Professor of Law, University of California, Berkeley "In this important study in constitutional and public law, Professors Sullivan and Frase take on a familiar concept-proportionality--that is widely revered as a benchmark for mediating between conflicting values and interests. They show, through their comparative work and analysis of American law, how the differing meanings of proportionality indicate different processes of assessment. We should be grateful to the authors for so impressively drawing out these varying meanings and for developing a set of principles of proportionality that safeguard key values in the process of judicial review."--Andrew Ashworth, Vinerian Professor of English Law, All Souls College, Oxford University "An important corrective for the practice of judicial review in American courts, Proportionality Principles in American Law argues that every intrusive government measure that threatens individual rights should undergo some sort of serious proportionality review. While proportionality principles are increasingly employed, courts have not been explicit about this fact and no unified theory has emerged; we can all be grateful for the conceptual groundwork and rigorous definitions developed here by E. Thomas Sullivan and Richard S. Frase. This book is certain to be an important addition to any public law scholar's library."--Herbert Hovenkamp, Ben V. and Dorothy Willie Professor of Law and History, University of Iowa