Constitutional law in social choice perspective

Constitutional scholars do not typically employ spatial reasoning in their work. And yet, constitutional jurisprudence and much work in judicial politics implicitly rest on assumptions best cast in spatial terms. These include assuming that positions in constitutional disputes, and the views of Supreme Court justices, generally lie along a common liberal-to-conservative ideological dimension. Although the single dimension assumption is often appropriate, it suffers inherent limitations. First, Supreme Court decision-making rules, both within and across cases, expose problems of dimensionality. Second, important substantive doctrines likewise reveal dimensionality. Third, and finally, throughout the Supreme Court’s history, positions deemed liberal (or conservative) in one period have emerged as conservative (or liberal) in a later period, suggesting that dimensionality is a persistent feature in our jurisprudential history. Social choice proves uniquely suited to explaining these important aspects of constitutional law. After briefly introducing the discipline of constitutional law and its relationship to social choice, this article offers three illustrations of how social choice analysis deepens our understanding of important substantive areas. The analysis exposes dimensionality within Supreme Court decision-making rules, within separation-of-powers doctrine, and over historical shifts in the liberal and conservative valence of once-prominent jurisprudential positions. Failing to appreciate dimensionality, which lies at the core of social choice theory, when studying the Supreme Court and constitutional law risks a truly one-dimensional understanding of a richer and multidimensional institution and body of doctrine.