What accounts for the explosion in the law school market for making lateral hires from other law schools? Law schools have long attempted to hire legal scholars from other schools. But the degree of competition for top laterals has become remarkable.

One indication is the huge number of law professors who will be visiting top law schools as reported in Leiter's Law Reports: 103, including Harvard (46), Stanford (4), Chicago (14), Columbia (20), NYU (19). Such visits are typically used to look over professors for a possible lateral offers, and clearly that is what is going on for a large number of persons on this list. The number of lateral visitors Harvard Law School will have next year will be double what the size of the whole faculty was in the 1950s.

Some of this will turn out to be professorial flirting, but a lot of these visits will result in actual lateral offers and moves. Consider the large, and highly prominent, set of laterals that have accepted offers from Harvard Law School during Dean Kagan's four year Kagan deanship: Noah Feldman, Jody Freeman, Jack Goldsmith, Daryl Levinson, Bruce Mann, John Manning, Gerald Neuman, Robert Sitkoff (just yesterday), Kathy Spier, George Triantis, Mark Tushnet, and Adrian Vermeule.

And the full returns are not even in yet on past visits, for Harvard still has outstanding offers out to: Yochai Benkler, Richard Ford, Pamela Karlan, Michael Klarman, Martha Nussbaum, Robert Post, William Rubenstein, Seana Shiffrin, Reva Siegel, Henry Smith, and Cass Sunstein. If even six out of these eleven outstanding offers are consummated, it will mean the addition of a total of 18 laterals, a remarkably sharp transformation of the school in a very short time.

What accounts for this explosion in competition for laterals? One might think the phenomenon is unique to Harvard. But the long list of visitors at top law schools indicates it is a more universal phenomenon. Still, there is a Harvard-centric theory. Namely, the Kagan deanship ended a certain amount of constipation in the Harvard laterals hiring process, and once Harvard started to aggressively pursue laterals, other law schools had to do so to keep up with the competition.

I think there is a certain amount of truth this. One individual can often make a remarkable difference, and Dean Kagan appears to have done so. But this explanation does beg the question: why didn't other law schools choose to compete by instead focusing more on the entry level market? There the level of hiring seems largely unchanged.

Other factors have also surely contributed to the current laterals frenzy. The large run up in the stock market last decade made donors and law schools relatively well-off, giving them the funds to pursue scholars and smaller class sizes. The revival of New York City by Guiliani made NYU and Columbia much more attractive places and helped them compete for top scholars. And all the top law schools have in recent years had deans who are young, smart, ambitious, and aggressive. But all these factors still fail to quite explain why these well-funded, more attractive schools with ambitious deans choose to focus more on laterals than on entry-levels, especially given that entry-levels do not require expensive visits and are generally easier to land because they are less likely to require a family-disrupting move.

I think the answer is related to a trend I mentioned yesterday: the death of doctrinalism. That death caused the entry level market to largely shift its focus to JD/PhDs as the set of persons who could, at the entry level, most plausibly offer demonstrable proof of their ability to engage in the sort of serious interdisciplinary work that modern law schools now require. But there is a relatively small set of such JD/PhDs to chase, so this strategy does not offer many opportunities for expansion. And it misses the large set of talented potential legal scholars who do not get PhDs.

One reaction to this limited pool has been to create fellowships to train JDs to do interdisciplinary work before they hit the entry level market. But this is a relatively new phenomenon and has not yet created a sufficient number of serious interdisciplinary entry level candidates to meet demand.

So the complementary alternative has been to use the laterals market to focus on those scholars who have proven their ability to do interdisciplinary work as professors elsewhere. We're often not sure which entry level candidates will turn out to be able to do such work, because many of them have not been given much of an opportunity to do so. But once they demonstrate such an ability in their scholarship, then the top law schools are all over them.

This explanation is consistent with the pattern of PhD hiring at the entry and lateral levels. For example, 6 out of 7 of Harvard's recent entry-level hires have (or will soon get) PhDs, and the one who does not was a quasi-lateral, having been a visiting professor here for two years first. In contrast, 9 of Harvard's 12 recent lateral hires have no PhD. I can attest that this pattern was not the product of any conscious design: it simply reflects which sorts of candidates seemed attractive.

Another trend that is consistent with this explanation is that lateral visits are now increasingly focusing on laterals much earlier in their career, often after they have been professors elsewhere for only a few years. This is a big change from the old model, where lateral offers generally focused only on fairly senior scholars who were the established leaders of their field. This shift makes sense if the shift to laterals reflects some substitution away from entry level hires because of the limited number of JD/PhDs, toward other young candidates who have demonstrated their ability to do interdisciplinary scholarship at another school. Look for more of the same in future, with some lessening of focus on laterals as fellowship programs expand to meet the demand for entry level candidates who can do interdisciplinary work without necessarily having PhDs.