Lawyer and part-time adjunct law professor [0] here. In terms of root-cause analysis, some of the comments to the NY Times article are thought-provoking --- they suggest that perhaps the urge for prestige and income, on the part of both students and schools, resulted in an upward ratchet for law-faculty salaries and thus for law-school costs, resulting eventually in a mismatch with market realities.

For example (all italics are mine):

"The question many have asked is why is law school so expensive .... [O]ther than books and space to sit in lectures and small sessions, what is there? Medical schools need labs, cadavers, hospitals, and other expensive equipment. Physicists need telescopes, rockets into space and expensive equipped labs. ...
But law school? Every time I hear that graduates are hundreds of thousands in debt, I wonder where the money went." --- from "Dale," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"The schools have little in expenses ... physical plant, library and professors. Students buy the only 'equipment': texts and laptops." --- from "Billy Bobby," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"As to the commenter who asked why law school is so expensive, try taking a look at the professor and dean salaries. [1] I was shocked when I learned what some of the professors and deans made at the third tier law school I attended. And, in my view, the school routinely admitted students who had no business being there, likely to pay the bloated salaries of the professors and deans." --- from "JJ," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"But in the mid- to late 1980s, he said, the school put an increasing emphasis on legal scholarship .... Across the country, many law schools were undergoing a similar evolution. It’s no coincidence that the average law school faculty began to grow quickly around this time: Each professor was teaching fewer courses to make time for research. ... Every law school seemed to want to emulate Harvard and Yale." --- from the article itself, not the comments

"I heard a lawyer say recently that in law school there were many students for whom the 'choice' to do law was more the result of a process of elimination. They are not able or interested in stem fields, but want the prestige and income of a white collar profession which the soft sciences don't necessarily provide, i.e. Sociology, social work, psychology. ... [T]his is why the field is saturated." ---from "Johanna," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"Make no mistake, the American Bar Association created this mess. The ABA has certified too many law schools and has placed ridiculous standards on these school thus driving up tuition to back-braking [sic] levels. Now law schools are admitting unqualified students to keep their numbers up. It is scary to observe many of these recent graduates. They are poorly read, lack critical thinking skills and are loosely educated." --- from "Peter," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"There are crushing unmet legal needs in communities across the country. Survivors of gender based violence lack representation. Police violence is uninvestgated. Predatory lenders prey on retirees." --- from "monte," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

"There is a genuine need for lawyers in this society. First, let's all get beyond the popular fantasy that they should all be upper middle-class. Yes, a minority can become well-paid attorneys. For the reset [sic], lower tuition, train them at public universities, and shut down the lawyer -mill expensive private places. Teach most to expect social worker-type salaries and conditions. Allow some loan forgiveness for those who work with the indigent. If nothing else, such an approach to legal training would attract people who would otherwise go into social work." --- from "Oceanviewer," http://www.nytimes.com/2016/06/19/business/dealbook/an-expen...

[0] Adjunct law professors are paid a pittance, so we're not part of the problem of escalating law-school costs --- we all have day jobs as lawyers or judges, and teach because we enjoy it and find it rewarding.

[1] I looked up the faculty salaries at my alma mater law school, at UT Austin, as reported by the Texas Tribune. Supposedly, the dean makes $466K; 64 full professors get a median salary $212K; one assistant professor gets $172K; one associate professor gets $122K; 18 lecturers get a median salary of $91K. https://salaries.texastribune.org/university-of-texas-at-aus...