Constitutional scholars do not typically employ spatial reasoning in their work. And yet, constitutional jurisprudence implicitly rests on a set of assumptions that can best be cast in spatial terms. This includes assuming that debated positions respecting constitutional issues, along with the views of Supreme Court justices, rest along a common liberal-to-conservative ideological dimension. Political scientists who embrace the Attitudinal Model are more explicit in this framing, which is itself a premise of those who code the Supreme Court Database upon which much quantitative work in the field of Judicial Politics takes place.
The assumption of a single analytical dimension is apt for much work on the Supreme Court and for many bodies of substantive constitutional doctrine. And yet, that approach suffers inherent limitations. First, Supreme Court decision-making rules, both within and across cases, expose problems of dimensionality. Second, important Supreme Court doctrines reveal embedded problems of dimensionality. Third, and finally, throughout the Supreme Court’s history, positions deemed liberal (or conservative) in one period have become conservative (or liberal) in the next, once more suggesting a long-standing feature of dimensionality throughout our jurisprudential history. Social choice proves uniquely suited to explaining these important features of constitutional law.
After introducing the discipline of constitutional law and its relationship to social choice, this Article provides three illustrations of how social choice analysis deepens our understanding of important substantive areas: exposing dimensionality within Supreme Court decision-making rules, within separation of powers doctrine, and in historical shifts in the liberal and conservative valence of once-prominent jurisprudential positions. Each discussion will necessarily be brief, but I will refer interested readers to additional sources that explore these examples and themes in greater depth. The central lesson from this Article is that failing to appreciate the role of dimensionality, which lies at the core of social choice theory and analysis for both the Supreme Court and constitutional law risks a truly one-dimensional understanding of a richer and multidimensional institution and body of doctrine.