Constitutional Rights, Private Law, and Judicial Power

The spread of constitutions with judicially-enforceable rights has transformed governance around the world. On the classical liberal view, constitutional rights have vertical effect: they regulate the hierarchical relationship between state authority and individuals. But rights can also have horizontal effect: they can regulate legal relations among private parties, and indeed, they do in practically all legal systems, to varying degrees. Rights have the potential to transform societies and their processes of governance most fully when they reach into private law, and they do so when they are given horizontal effect by courts.;This dissertation develops a theory to explain why and how courts give horizontal effect to constitutional rights, and with what effects. Its core is a structured, focused comparison of how rights are deployed horizontally within three jurisdictions: Germany, Canada, and the United States. Courts begin applying constitutional rights horizontally in order to meet normative demands not satisfied by ordinary (non-constitutional) law, but only when normative and strategic logics favor this move. Over time, courts develop horizontal effect doctrine that attempts to justify case outcomes with respect to a larger normative narrative, and also serves as an argumentation framework that litigants can access to press new claims. Horizontal effect doctrine can set off a constitutional cascade, in which rights reasoning spreads to more and more sites and modes of governance, blurring the lines between constitutional law and ordinary law and between the work of courts and legislatures. The dissertation traces the process by which doctrinal choices, in combination with system-specific institutional and normative features, can lead to either a constitution cascade or a different equilibrium outcome. By taking account of the horizontal dimension of rights, this study offers an expanded view of the work that constitutional rights do in contemporary systems of governance.