I'm on record as believing (1) that there is a bias against hiring conservatives in legal education and (2) that that bias has more to do with network effects that actual subjective intent. Note I said "more to do." It's not all network effects. There are die-hard left-liberal law professors who simply will not vote to hire anyone to the right of, say, Bill Clinton.
It looks like we may have a case in point at the University of Iowa. Walter Olson has been on top of this story for a while, but the case is so obvious that even the NY Times deigned to cover it. In the Times report, we learn that a conservative law faculty applicant may have generated opposition expressly on the basis of her politics:
“Frankly, one thing that worries me is that some people may be opposed to Teresa serving in any role, in part at least because they so despise her politics (and especially her activism about it),” Associate Dean Jonathan C. Carlson wrote in 2007 to the law school’s dean, Carolyn Jones.
Personally, I can think of a hell of a lot of my colleagues at UCLA and formerly at Illinois for whom I would not have voted if I had taken into account their left-liberal activism. But I didn't oppose them, because that's profiling and profiling is wrong (or so they tell me).