The DC Circuit is considering a petition for rehearing en banc in Halbig (the Affordable Care Act case). I have no opinion on what the Court should do, and I think that it’s silly for outsiders to advise judges on a discretionary matter. (In other words, there is no “expertise” on whether to go en banc.)
I thought this would be a good opportunity, though, to reflect on how circuits differ with respect to en bancs. Some have many and others have few. Why is that? One answer is that large circuits (I’m talking to you–Ninth) tend to go en banc more often. In part this is because a panel is more likely to be unrepresentative of the court as a whole, and in part because large circuits are just less collegial because there are more judges who live further apart. Another thought is that circuits that are badly split along ideological lines (I’m talking to you–Sixth) go en banc more often.
But there is also a distinctive culture that develops in each circuit about this issue. The Second Circuit (where I clerked) has long had a strong aversion to going en banc. (Indeed, the year that I clerked there were no en banc hearings.) This practice is usually attributed to Learned Hand, who thought that en bancs were a waste of time and showed disrespect for the judges on the panel. I think all of us would be interested to hear from former DC Circuit clerks about their thoughts on the norms there.