Using 1994-1995 and 2002-2003 data, Nieswiadomy (1998, 2006) found that economics majors scored well on the LSAT. These results are frequently posted on university web sites by Economics and other departments. This note, which updates the prior studies using current 2007-2008 data for the 2008-2009 class of students entering law school, finds that Economics majors still perform at or near the top of all majors taking the test. Economics majors (LSAT score of 157.4) are tied for first (with Philosophy) of the 12 largest disciplines (those with more than 1,900 students entering law school). Economics is tied for second (with Philosophy/Religion (157.4)) behind Physics/Math (160.0) in a set of 29 discipline groupings that are created to yield at least 450 students with similar majors.Paul Caron also reproduces a table with the results.
What explains these results? Certainly there could be some amount of self-selection. For instance, I think it's reasonable to assume that only a small portion of physics and math majors take the LSAT, and it is possible that those who take the LSAT have have a greater aptitude for legal reasoning (insofar as that is what the LSAT tests) than do physics and math majors generally. But I also think the data suggests that those disciplines that place a greater emphasis on logic and syllogistic reasoning are better preparation for the LSAT than those that do not.
UPDATE: An interesting thought from the comments: The nation's most selective universities are less likely to offer a "Prelaw" major, therefore the results may reflect the fact that a Yale undergraduate who wants to go to law school may be a history or philosophy major, while an undergrad with the same interests at a less selective school might major in Prelaw or criminal justice. Also, it's curious that the study does not group political science and government majors. Assuming that few schools offer both majors, is it possible that more selective schools are more likely to offer one than the other? Might that explain the three point difference in LSAT averages between the two groups?