James Cleith Phillips has just posted Testing a Beckerian-Arrowian Model of Poltical Orientation Discrimination on the U.S. Law Professor Labor Market: Measuring the "Rank Gap", 2001-2010. Here's the abstract:

There are comparatively few conservative and libertarian law professors on U.S. law school faculties. Why is this? One possible explanation is discrimination based on political orientation. This paper tests this using a model of discrimination based on the work of Nobel Prize-winning economists Gary Becker and Kenneth Arrow in order to measure the "rank gap"—the difference in the ranking of a hiring law school based on one's political orientation after controlling for other predictors of that ranking (clerkships, publications, the law school one graduated from, etc.).

The paper, using matching statistical methods, finds that upon comparing conservative/libertarian law professors hired from 2001-2010 with equally-credentialed liberal law professors, conservatives/libertarians end up, on average, at a law school ranked 12-13 spots lower (i.e., less prestigious). … This rank gap is not uniform, being more moderate with the top 75 schools, non-existent with schools 76-100, and the largest with the lowest-ranked schools. … The paper finds a similar "rank gap" for law professors whose political orientation was unknown or moderate compared to their liberal peers. Thus, while there may be other mechanisms causing the dearth of conservative/libertarian law professors in the legal academy, those who do make it in the door appear to experience discrimination based on political orientation.

The paper also discusses the harms that a lack of conservative/libertarian law professors causes. Namely, legal scholarship suffers from an echo chamber; law students, particularly liberal ones, may not sufficiently learn how to make or counter conservative and libertarian arguments; and law and policy is not as strong as it could be without conservative/libertarian critiques and perspectives. …