One interesting thing about this study is that, at some schools, there is a substantial gulf between the measured scholarly impact of the tenured faculty and the U.S. News peer reputation score (which is supposed to measure the quality of the faculty) — to say nothing of the variance between the scholarly impact score and overall U.S. News rankings. For instance, my own institution (Case Western Reserve University School of Law) ranks 25 in this rating, which is substantially higher than either U.S. News measure.
This sort of ranking has some obvious limitations. Academic citations are but one potential measure of a school’s scholarly impact, and scholarly impact is but one measure of a law school faculty. Nonetheless, this sort of ranking system provides some measure of which faculties (and which scholars) have had the greatest impact on legal scholarship in recent years.
UPDATE: I should also note that the George Mason University School of Law (my alma mater and the home of several VC contributors) is ranked 21, which is much higher than its U.S. News ranking.