Judicial capacity and the substance of constitutional law

Courts can decide only a small fraction of constitutional issues generated by the American government. This is widely acknowledged. But why do courts have such limited capacity? And how does this limitation affect the substance of constitutional law? This Essay advances a twofold thesis. First, constraints on judicial capacity derive from a combination of the hierarchical structure of the judiciary and broadly held judicial norms. Second, in certain important constitutional domains, these constraints create strong pressure on courts to adopt hard-edged categorical rules, defer to the political process, or both. The argument is mostly positive but has significant normative implications. In particular, the constraints of judicial capacity suggest a new and previously unexplored justification for courts to defer many constitutional questions to the political process. Capacity constraints also help to explain the reluctance of courts to challenge political majorities, diminishing though not eliminating the countermajoritarian difficulty. For these reasons and others, judicial capacity deserves a central place on the agenda of constitutional theory.