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This article draws on novel data and presents the results of the first empirical analysis of how potentially salient characteristics of Court of Appeals judges influence class certification under Rule 23. We find that the ideological composition of the panel (measured by the party of the appointing president) has a very strong association with certification outcomes, with all-Democratic panels having dramatically higher rates of certification than all-Republican panels—early triple in about the past twenty years. We also find that the presence of one African American on a panel, and the presence of two females (but not one), is associated with pro-certification outcomes.

Our results show that, contrary to conventional wisdom in scholarship on diversity on the Courts of Appeal, the impact of diversity extends beyond conceptions of “women’s issues” or “minority issues.” The consequences of gender and racial diversity on the bench, through application and elaboration of certification law, radiate widely across the legal landscape, influencing implementation of consumer, securities, labor and employment, antitrust, insurance, product liability, environmental, and many other areas of law. In considering possible explanations for our findings on the pro-certification preferences of female and African American judges, we note that class action doctrine, as trans-substantive procedural law, traverses many policy areas. As strategic actors, it would be rational for judges to take into consideration how class certification doctrine in a case that does not implicate issues on which they have strong preferences might affect certification in cases that do. Alternatively, or in addition, our results may be the first evidence that trans-substantive procedural law affecting access to justice is itself a policy domain in which female and African American judges have distinctive preferences. In either case, the results highlight the importance of exploring the effects of diversity on trans-substantive procedural law more generally.

Our findings on gender panel effects in particular are novel in the literature on panel effects and the literature on gender and judging. Past work focusing on substantive anti-discrimination law found that one woman can influence the votes of males in the majority (mirroring what we find with respect to African American judges in class certification decisions). These results allowed for optimism that the panel structure—which threatens to dilute the influence of underrepresented groups on the bench because they are infrequently in the panel majority—actually facilitates minority influence, whether through deliberation, cue taking, bargaining, or some other mechanism.

Our gender results are quite different and normatively troubling. We observe that women have substantially more pro-certification preferences based on outcomes when they are in the majority. However, panels with one female are not more likely to yield pro-certification outcomes. Female majority panels occur at sharply lower rates than women’s percentage of judgeships, and thus certification doctrine underrepresents their preferences relative to their share of judgeships and overrepresents those of male judges.

Publication Citation

109 Mich. L. Rev. __ (forthcoming).