Judicial capacity and the substance of constitutional law.

• Author: Coan, Andrew B.

ESSAY CONTENTS INTRODUCTION I. THE LIMITS OF JUDICIAL CAPACITY II. A JUDICIAL CAPACITY MODEL OF SUPREME COURT DECISIONMAKING A. High-Volume Legal Domains B. High-Stakes Legal Domains C. Hybrid Legal Domains D. Summary III. CAPACITY AND COMMERCE IV. NORMATIVE IMPLICATIONS A. Judicial Capacity and the Constitutional Choice Set B. Judicial Capacity as Independent Normative Metric C. Judicial Capacity and Judicial Competence D. Judicial Capacity and Judicial Independence V. CAVEATS CONCLUSION INTRODUCTION

Start with a very basic premise: courts can decide only a small fraction of the constitutional issues generated by the American government. By now, this is something of a commonplace among constitutional theorists. But it is a commonplace of a peculiar sort. It receives frequent lip service but is almost never taken really seriously. Advocates for more expansive constitutional protections routinely brush aside, or outright ignore, the judiciary's limited capacity. Opponents of such protections routinely write as if "government by judiciary" were a real and worrisome possibility. Meanwhile, there has been very little work exploring why the judiciary has such limited capacity or how we should expect this limitation to affect the substance of its constitutional decisions.

This Essay is the beginning of an attempt to take judicial capacity seriously. My thesis is twofold. First, the constraints on judicial capacity are a product of both the structural organization of the judiciary and certain widely shared but little-discussed normative commitments of American judges. Second, in certain important constitutional domains, these constraints create an almost irresistible pressure on courts to adopt hard-edged categorical rules rather than vague standards and a very strong pressure to defer to other government actors. After explaining each of these points in more detail, I apply them to the Supreme Court's recent Commerce Clause decisions as an illustrative example. My argument is mostly positive, but I conclude with a few thoughts on its normative implications, which I believe to be quite significant.

Before I begin, it is necessary to distinguish what I will be calling judicial capacity from two other attributes of the judiciary that sometimes go by that name. By judicial capacity, I mean the total volume of cases the court system is capable of handling. I do not mean the capacity of the judiciary to produce reliably good decisions, which I shall call judicial competence. Nor do I mean the capacity (or inclination) of the judiciary to produce social change against the tide of dominant political forces, which I shall call judicial independence.

Both judicial competence and judicial independence are the subjects of substantial literatures. Indeed, in one form or another, they have dominated the agenda of constitutional theory for more than half a century. For decades, theorists have debated whether courts represent a reliable "forum of principle" or an imperious aristocracy; (1) whether courts possess the factfinding tools and expertise to make reliable decisions on empirically difficult constitutional questions; (2) whether courts are meaningfully independent of the political process; (3) and if so, whether they are capable of producing meaningful social change in the teeth of political opposition. (4) That these questions have garnered substantial attention is hardly surprising. They are obviously important.

The principal aim of this Essay is to show that judicial capacity is comparably important. This claim rests on three premises. First, the constraints on judicial capacity help to explain the shape and evolution of many important constitutional doctrines. The Commerce and Equal Protection Clauses are two examples. In both contexts, the Supreme Court has adopted a broadly deferential posture toward the political process. And on the relatively rare occasions when it engages in serious review, it does so in the form of relatively hard-edged categorical rules that clearly insulate the vast majority of political action from serious scrutiny. Many of these rules are difficult to explain except as responses to the constraints of judicial capacity.

Second, capacity's influence on doctrine is a crucial determinant of judicial competence, one that constitutional theorists have almost completely overlooked. In particular, when the Court attempts to second-guess the political process, capacity constraints generally force it to do so in the form of crude categorical rules. This dynamic, in turn, produces constitutional doctrines that are at best crude proxies for the underlying purposes they are meant to serve. The pressure that capacity constraints place on the Court to employ such functionally unsound rules provides an important, though not necessarily dispositive, reason to distrust the Court, quite apart from the standard arguments about judicial expertise, information, and democratic unaccountability.

Third, the constraints on judicial capacity impose important limits on the judiciary's ability to challenge dominant political forces. These limits too have been largely overlooked. (5) Simply put, capacity constraints generally force the Court to adopt a posture of deference toward the political process. To do otherwise would invite more litigation than the judiciary could handle. But of course, it is difficult to challenge dominant political forces while adhering to a broad policy of deference. This is not to say that the Court will never swim against the tide of public opinion, but the limits of judicial capacity sharply constrain its ability to do so. Better understanding those limits therefore promises to enrich our understanding not only of the substance of constitutional law but also of judicial competence and judicial independence, two of the central preoccupations of American constitutional theory.

The Essay unfolds as follows. Part I explains the source and character of the constraints on judicial capacity. Part II lays out a positive theory of the influence of judicial capacity on the substance of constitutional law. Part III discusses the Supreme Court's recent Commerce Clause decisions as an illustrative example of the theory. Part IV draws out normative implications. Together, these Parts provide a brisk, broadly drawn overview of judicial capacity and its importance for constitutional law. Part V adds nuance and shading, in the form of several important caveats.

1. THE LIMITS OF JUDICIAL CAPACITY

   The most important work on judicial capacity traces the limited capacity of the courts to the pyramid-like structure of the federal judicial system, with the ninety-four district courts as its broad base, the thirteen courts of appeals as its somewhat narrower middle section, and the "one supreme Court" mandated by Article III as its apex. (6) The theory is that having just one court at the apex of the system, just one court that possesses authority to make nationally binding decisions of federal law, creates a kind of bottleneck. The capacity of the system as a whole is constrained by the capacity of the single court that sits at its top. (7)

   This structural explanation is an important part of the story, but it is not the whole story. We can see that rather easily once we recognize that nothing in the hierarchical structure of the judiciary requires the Supreme Court to approach its work in any particular way. Specifically, nothing in the hierarchical structure of the judiciary requires the Court to spend as much time on--or to approach with the degree of seriousness that it does--the cases that it decides. If the Justices were so inclined, they could decide cases by coin flip instead of by briefing and oral argument. Coin flips are fast. The Court could do an effectively unlimited number of them per year. If the Justices approached their decisions in this way, they would totally eliminate the bottleneck at the top of the American judiciary. Alternatively, the Court might delegate final decisional authority to individual Justices or even their law clerks. Neither would eliminate the Supreme Court bottleneck as would decision by coin flip, but either would expand the Court's decisional capacity fairly dramatically.

   Of course, none of these is a remotely plausible scenario. But the mere fact that they are possible without abandoning the hierarchical structure of the judicial system shows that this structure alone cannot explain the limited capacity of the judiciary. Any full explanation of the limits on judicial capacity needs to account for the widely shared judicial norms that make it unthinkable for the Court to decide cases by coin flip or in other ways that might radically expand its capacity relative to what the structural theorists have assumed that capacity to be. (8)

   What are those norms? The first and most basic is a commitment to maintaining minimum professional standards of judging. (9) At the Supreme Court level, this involves an elaborate briefing process, oral argument, internal deliberation, and public justification of the Court's decisions--all of which are expensive and time-consuming. Adherence to this norm alone probably caps the capacity of the Supreme Court at somewhere between one hundred fifty and two hundred full-dress decisions per Term, roughly what the Court decided at its peak in the early twentieth century. (10) This may not seem that constraining, given that the modern Supreme Court routinely decides fewer than one hundred cases per Term. (11) The appearance, however, is deceiving. Had the Court interpreted the Commerce, Equal Protection, or Takings Clauses differently--to pick just a few examples--the demands on its capacity would be vastly higher. That the Court has shaped constitutional law to avoid overwhelming its modest capacity should not be taken as evidence that this capacity is unlimited or overabundant. (12)

   Of course, the Court's jurisdiction is almost entirely...