Much of that comes from taxpayers in the form of federal student loans. Steven R. Smith, dean of the California Western School of Law, described this sum as “the equivalent of an involuntary fee” that students must pay to get a diploma. “It is not obvious that students are the ones who should be paying the cost of legal scholarship. They are generally borrowing the money to do this and they are the least able of all those in the profession to pay for it.”

The Prestige Game

About half of all law school hiring begins at the Faculty Recruitment Conference, widely known as the meat market, held by the Association of American Law Schools. It is conducted every year at the Marriott in the Woodley Park neighborhood of Washington.

At this year’s conference, in October, nearly 500 aspiring law professors turned up for interviews with 165 law schools. Like the draft of every professional sport, there are superstars here and for two days they were hotly pursued. At the top of the pile were former Supreme Court clerks. Just under them were candidates with both a J.D. and a Ph.D. in another discipline. Law schools, especially those in the upper echelons, have been smitten by Ph.D.-J.D.’s for more than a decade.

Ori J. Herstein, who studied philosophy in grad school and is a doctor in the science of law, says that “an economics Ph.D. is the most valuable,” and that “the further away you get from the humanities the better.”

Mr. Herstein was sitting in the Marriott lobby between interviews. Israeli-born and cheerful in a boyishly wonky way, he has a résumé that seems custom-built to tantalize law school recruiters. He has two degrees from Columbia, which, along with a handful of other elite schools — most notably Yale — has become a farm team for the credential-obsessed legal academy. He has already published a handful of law review articles with promisingly esoteric titles (“Historic Injustice and the Non-Identity Problem: The Limitations of the Subsequent-Wrong Solution and Towards a New Solution”) and has submitted another that sounds perfectly inscrutable (“Why Nonexistent People Do Not Have Zero Well-Being but Rather No Well-Being”).

This type of scholarship, and the cash that keeps the law review conveyor belt spinning, are defended by law school professors as a way to attract the best and brightest to teaching. It is also said to enhance the prestige and sophistication of the American legal system. “Students want renowned scholars to teach them, period,” said Francis J. Mootz III, a professor at the William S. Boyd School of Law at the University of Nevada and the author of “Neo-Aristotelian Praise of Postmodern Legal Theory. “They want to learn from the best and brightest.”

It is true that a law school’s reputation, and the value of its diplomas in the legal market, are almost entirely bound up in the amount and quality of the scholarship it produces. That’s been especially so since the late ’80s, when U.S. News and World Report started to rank law schools. The publisher’s annual rankings all but define a school’s standing in the legal academy’s firmament, and 40 percent of the U.S. News algorithm is based on a “quality assessment” survey by hundreds of lawyers, judges, deans and professors.