Introduction: the empirical revolution in law.

• Author: Ho, Daniel E.

1. IMPETUS II. SKETCH III. THEMES I. IMPETUS

   In November 2012, Stanford Law School hosted the Seventh Annual Conference on Empirical Legal Studies (CELS), purportedly "the largest annual refereed academic legal conference in the world." (1) Of the forty-some members of Stanford's law faculty, nearly thirty became integrally involved with the program, reflecting an enormous shift in interest over the years. We see this same shift in the proportion of articles in the Stanford Law Review invoking empirical work, which (as Figure 1 shows) has skyrocketed over the decades.

   [FIGURE 1 OMITTED]

   How did this come to be? What role does empirical work play in law'? Where is that work leading? And why might (or might not) one be skeptical? Rather than answer these questions abstractly and top-down--a near-impossible task--this issue of the Stanford Law Review addresses these questions bottom-up, through the lens of particular substantive fields. It selects some of the best papers presented at CELS as a springboard to contextualize the intellectual history of questions in the field, to provide a sense of why empirical work has become so important in legal scholarship, and to develop a more affirmative vision for empirical work in law.

   The Essays in this volume cover six different fields--civil procedure, contracts, constitutional law (specifically, election law), criminal law, corporate governance, and law and philosophy--and demonstrate the unique, field-specific, and vibrant role of empiricism across different areas of law. While some areas have a long history of empirical work (criminal law being the obvious example), in others this kind of work is relatively new, raising unique questions about its interplay with different disciplines (e.g., civil procedure or experimental philosophy). The choice of fields is not meant to be comprehensive, but rather to illustrate empiricism's engagement across diverse areas. (3)

   Such analysis is in many ways natural for Stanford, which has a long tradition of engagement with legal empiricism. Lawrence Friedman, one of the early proponents of law and society and its "law in action" approach, joined the faculty in the 1960s. (4) Bob Rabin conducted one of the first quantitative studies of prosecutorial discretion in the 1970s. (5) Deborah Rhode deployed surveys to assess enforcement of the unauthorized practice of law and the legal profession in the 1980s. (6) And the addition of scholars like John Donohue and Deborah Hensler in the 1990s, and Rob Daines, Dan Kessler, Alison Morantz, Joan Petersilia, and a number of others in more recent years, has strengthened the empirical turn. But Stanford's receptivity to empirical work stems not just from faculty members who specialize in such work, but from the engagement by and with the faculty at large. The contributors to this volume, though not all principally empiricists, represent this broad level of empirical engagement. Each of them brings a long-term synoptic vision of his or her field to consider how the empirical movement has unfolded within it, in spite of its many fits and starts. (7)

2. SKETCH

   In The Twiqbal Puzzle and Empirical Study of Civil Procedure, David Engstrom describes how "a hundred empirical flowers have bloomed" (8) around the question of the effects of Bell Atlantic Corp. v. Twombly (9) and Ashcroft v. Iqbal, (10) or "Twiqbal," which heightened the pleading standard in civil litigation. Engstrom attributes this blossoming of interest to a combination of easily available evidence (most notably in the form of docket sheet data) and advances in statistical methods. But he also questions how well those methods have been deployed. Roughly ten years have passed since Lee Epstein and Gary King excoriated law reviews for publishing so much empirical work that violated basic rules of inference, (11) yet Engstrom documents how much this pathology persists in the context of Twiqbal. Researchers commonly introduce sampling bias, omit key confounding covariates, and fail to adjust for potential selection effects. Moreover, many of these design errors hinge on substantive questions: focusing on claims as opposed to parties as the unit of analysis, for example, may exaggerate the impact of Twiqbal, as some plaintiffs will still remain in court. In an informal recta-analysis of studies purporting...