In the latest issue of the Green Bag, David Garrow has a very interesting discussion of the ideological leanings of feeder judges and the impact they may have on the internal workings of the Supreme Court. (Feeder judges, for those unfamiliar with the term, are lower court judges whose clerks often go on to clerk for the Supreme Court.) Garrow notes that many feeder judges are considerably more ideological -- that is, less politically centrist -- than is typical for appellate judges. Garrow writes:
[I]n recent decades virtually every [feeder judge] has been either exceptionally liberal or highly conservative and almost none have been politically difficult to pigeonhole.
For instance, the D.C. Circuit has long enjoyed an overall numerical advantage, but why is it that judges Silberman, Sentelle, and Williams, just like judges Bazelon, Wright and Mikva in earlier years, score far above equally well-respected but ideologically moderate jurists like Judith W. Rogers? Similarly, in a national context, why have judges Luttig and Kozinski topped the charts rather than say judges Michael Boudin, Pierre Leval, and the late Edward Becker? The explanation is not that the Fourth and Ninth Circuits have decidedly stronger reputations than the First, Second, or Third, nor that clerks to judges like Silberman are decidedly more able than clerks to a Boudin or Leval. If instead the real answer is simply that multiple justices have closer personal ties to judges like Luttig, Silberman and Kozinski than Rogers, Boudin, and Becker, then the justices have only themselves to blame for a "clerk force" whose political loyalties are far more partisan than was the case in earlier decades when clerks did not undergo the ideological socialization that they now receive during their appellate clerkships.
Garrow speculates that training by ideological feeder judges has created a more ideological Supreme Court. The dynamic, Garrow suggests, is that feeder judges train law clerks to wage ideological battle. Those clerks naturally take the same approach when they get to the Supreme Court:
Law clerks who come to the Supreme Court already socialized into a highly political and ideologically oriented view of appellate decision-making may not best serve either their justice or the Court. Instead they may be predisposed toward what Judge Posner rightly calls the "disreputably partisan" behavior so richly documented in case files from Justice Blackmun's latter years on the Court.
I suspect Garrow has an exagerrated sense of how much court of appeals judges influence their clerks. Most appellate clerks have some pretty settled ideas about the law before they start their clerkships. At the same time, the ideology of feeder judges may be important because judges often prefer to hire clerks with views roughly similar to their own. It seems plausible to say that if feeder judges are unusually ideological, on average they will probably tend to hire clerks that are pretty ideological; if feeder judges are more centrist, on average they will probably tend to hire clerks that are more centrist. Exceptions exist, obviously, but this seems like a decent rule of thumb.
So are feeder judges more ideological than most? That may be right, although the evidence is more mixed than Garrow lets on. For example, Judge Kozinski doesn't fit well along the left-right axis; his libertarian leanings make him "conservative" in some areas and "liberal" in others. (I must know 20 or 30 Kozinski clerks, and on the whole they're pretty hard to pigeonhole politically.) To the extent Garrow's point is right, I suspect there are a bunch of possible expanations. First, part of it is probably just a coincidence, the result of close personal connections between Justices and particular judges. (For example, Judge Luttig clerked for Scalia and helped Thomas prepare for his confirmation hearings.) Second, Presidents looking to move the courts to their side have an incentive to put bright, young, connected, and politically predictable nominees on the circuit courts; those bright judges are more likely to become feeder judges. Third, some Justices may want clerks with a particular set of views, as the Justices may have those views, too. Finally, successful feeders are often natural lobbyists who try to "sell" their clerks to the Justices. Perhaps a rough correlation exists between perceived ideology and willingness to pursue the sale.
UPDATE: Garrow's piece is now online here, thanks to Howard Bashman.