Three and four decades ago, students of the courts such as Walter Murphy and S. Sidney Ulmer paid particular attention to how the group context shaped judicial behavior and court outcomes, drawing on the political and social psychology research of the day. However, contemporary scholars pay attention to the group context for appellate court decision making only to the extent that it provides an opportunity for strategic behavior. But judges, as human beings, are profoundly affected by the identities of those with whom they make decisions and the norms of the environments within which they make those decisions. I would argue that not all of those concerns are, strictly speaking, strategic in nature.
To illustrate, consider designated judges. The chief judge of a circuit has the authority to temporarily assign (designate) a district court judge from his circuit to serve as part of an appellate panel. According to data available from the Administrative Office of the Courts, designated judges account for upwards of twenty percent of all case participations in the United States Courts of Appeals. Though some of these designated judges are circuit court judges serving from other circuits, the majority are district court judges. A basic question is whether these designated district court judges are fungible with their circuit court colleagues or if their status as district court judges affects their ability to be fully equal partners in the deliberative process. Work that appears in Law & Society Review in 2001 by Brudney and Ditslear ("Designated Diffidence: District Court Judges on the Courts of Appeals") provides some insight into this question, as does earlier work by Thomas G. Walker that appeared in the American Journal of Political Science in 1973 ("Behavioral Tendencies in the Three-Judge District Court).
Think, too, about how the presence of a designated judge may affect the behavior of the regularly sitting appeals court judges with whom he sits. Much of the workload of the United States Courts of Appeals consists of cases appealed from the federal district courts. Do the regularly sitting appeals court judges reviewing a district court ruling in the company of a designated district court judge approach that review in the same way or do they suppress the error correction function inherent in the appellate court process in deference to their district court colleague?
I am intrigued by this line of inquiry precisely because it represents an empirical question the answer to which has important implications for a normative concern. (Or, if you like, a normative question to which empirical evidence can be brought to bear.)