Bear with some meandering musings below....
To grossly oversimplify the history of the American Bar Association accrediting law schools, it looks something like this.
About a hundred years ago, just about anyone could take a bar exam, as long as you studied with a lawyer or "read law" for a time. Some attended law school, but it was not required. By the 1930s, states began making it more difficult to pass the bar exam--presumably in part to reduce competition for existing lawyers and make the profession more difficult for individuals to enter. (Presumably, of course, with another, at least salutary, benefit of increasing the "quality" of those practicing law.)
The ABA today describes its accreditation standards as "minimal educational requirements to qualify a person for eligibility to sit for the bar examination." As state bars became more exclusionary, these bars began to adopt minimal standards--driven, perhaps, by the ABA itself, which has become the sole accrediting body in most jurisdictions. The bar required attendance at an accredited law school; the accreditation process was designed to ensure that legal education met standards that the ABA believed to offer a "sound program" of legal education.
All this is actually quite descriptive and lacks any normative explanation. Why should there be certain standards for legal education that must be met before someone takes the bar exam?
What is the difference between legal education and the bar exam?
Perhaps we have legal education we believe that attorneys should be, somehow, perhaps, well-rounded and well-educated individuals, apart from their ability to pass the bar exam? That would seem to be the driving concern--we think (perhaps you don't, but work with the assumption) lawyers shouldn't just be able to pass the bar and practice law; they should have some kind of training and background before they practice law and something that qualifies them apart from the bar exam's test of "minimum competence."
The ABA has a near obsessive focus on the picayune details of how a law school functions, including the types of books the law library maintains. Many of the ABA standards are fairly generic, requiring things like "suitable" classrooms, "sufficient" space for staff, and "sound" admissions policies. Ensuing interpretations often add specific guidance to these generic standards, which drive a great deal of law school decision-making. But these are all designed to elevate the educational experience, quite apart from the ability to pass the bar exam.
Many of these standards, of course, suffer from serious deficiencies. For matters like the books in a library, they are antiquated notions about access to print materials from an era where books were scarce. Today, not only are books plentiful, the resources attorneys principally use are electronic. Some standards are the result of bargains with entrenched interests within the ABA rather than with empirical or quantifiable pedagogical benefit.
But that can be set aside for the moment--the ABA may have a goal of providing some kind of a quality education for all prospective attorneys before they take the bar, but it may simply do so a but ham-handedly.
But there is a different, perhaps reverse, form of the question: if legal education provides students with three years of sound education and a degree at the end, why is the bar exam even needed? Isn't graduating from a law school after three years of thickly-regulated education sufficient to make one eligible to practice law? Indeed, it's a reason why the state of Wisconsin offers "diploma privilege" to graduates of its two law schools.
The opening question, then, is really to determine the purpose of the bar exam and the purpose of accreditation of law schools.
To recap, the bar exam has perhaps less-than-noble purposes (such as limiting the pool of attorneys), and some perhaps good purposes (such as establishing minimum competence to practice law, however imperfect the bar exam may establish that).
Legal education, in contrast, is, I think, designed to offer something beyond simply establishing "minimum competence." It, perhaps, and perhaps ideally, offers students an opportunity to learn about the law in a more systematic way than reading law might have permitted. That, of course, comes at a high cost for prospective attorneys who must invest (typically) three years of education and a substantial sum of money to achieve the diploma required to take the bar.
Therefore, I think it would be fair to say that legal education is providing something distinct from the bar exam. (Whether the accreditation process is a proper assessment, and whether accreditation should be required, are separate concerns.)
If legal education is providing something distinct from the bar exam, then why are new accreditation standard focusing on the bar exam?
So, why is the ABA still accrediting law schools given its new obsession with the ability of graduates to pass the bar exam?
Most of the rest of the ABA's accreditation practices focus upon the terms of education. It is, in theory, providing something apart from the bar exam. Now comes the new ABA standard, on track for approval, which provides, quite flatly, "At least 75 percent of a law school’s graduates in a calendar year who sat for a bar examination must have passed a bar examination administered within two years of their date of graduation." An earlier malleable standard has become a clean rule. It also threatens a number of schools currently in non-compliance with this standard, likely to get worse as bar rates continue to decline.
What value is the ABA adding if its newest, most stringent control is simply redundant of, well, the bar exam itself? Why have accreditation at all?
It seems a bit self-referential to say that a law school cannot send its graduates to take the bar exam until enough of its graduates pass the bar exam--particularly as the entire point of legal education, as I've suggested, is to provide something apart from "minimum competence."
After all, it would be pretty simply stuff for state bars to simply disclose the pass rates of all institutions whose graduates take the bar exam. Then consumers could know if their school met the standards that they expected or desired when attending law school.
But perhaps it is because of the consumer protection-focused nature of recent years that has driven this result. Legal education is not really seen as offering something "apart from" anymore. It is instead deemed more a necessary and costly hurdle before taking the bar exam. And if law school graduates are going through this costly and time-consuming process, but unable to pass the bar exam, then their function is greatly diminished.
There are two principal, and opposing, kinds of responses one could make to my query.
First, I suppose one could make the claim that if a law school is not providing "minimum competence" to its graduates, then it is hardly providing the kinds of aspirational traits legal education purports to provide and should not be accredited. That's, I think, somewhat misguided. The bar exam is not really very well designed to test "minimum competence." Indeed, it's not really very well designed to test the abilities of lawyers. Timed, closed-book essays that principally rely on regurgitating black letter law (indeed, often greatly simplified, even fictitious versions of law), alongside a series of multiple choice questions, in selected areas of practice designed for general practitioners who arose from a common-law, 70s-era form of the law, are not really something that should be taught in law school--at least, not emphasized.
In reality, the problem is not that law schools are failing to train their graduates with the "minimum competence" needed to practice law. Or, even the ability to pass the bar. It is that many are accepting, and then graduating, students who are unable to acquire the skills needed to pass the bar--because they are incapable of doing so, or because they are unable to transfer the three years of legal education into the licensing regime of bar test-taking, or because they have been prioritizing other things, or whatever it may be.
This is, I think, a subtle point. It is tied, I think, closer to admissions and graduation practices, and to post-graduation study habits, more than legal education. That is, of course, because legal education is supposed to be providing something other than bar prep, and has been doing so for decades. So, the decline in bar pass rates is not really a problem with "education" in the sense of the time in the classroom for three years. It is about other things.
Second, one could say that the ABA needs to have some standards for accrediting law schools, and this is as good a standard as any to help control the admissions and graduation problems that may be contributing to bar pass rate declines. But this, again, gets back to my opening question--why have accreditation at all?
If law schools aren't in the business of bar exam training (and I don't think they should be), we should still expect that law schools are graduating students who are able to use their professional degrees in the practice of law. If schools are failing in that endeavor, stripping accreditation is certainly a way of penalizing them.
But it all seems quite circuitous, given that we could just permit students to take the bar regardless of their legal education history--as long as they establish that they have the "minimum competence" to take a licensing exam, they could practice law. And if some want to attend law school to secure a credential for future employers that says, "I've attended this law school and have some additional training that establishes something beyond minimum competence," they could do that, too.
And this points back to the purposes of requiring attendance at an accredited law school in the first place. You see, my problem isn't necessarily that the ABA wants to ensure that law schools are graduating students who are able to pass the bar exam and become licensed practicing attorneys. It is, instead, that if the bar exam is our principal concern, and the principal concern is wholly independent of legal education, and now legal education is accrediting bodies based on performance on this principal concern... doesn't that instead suggest that the accreditation process of legal education is, perhaps, its own problem now?
If you've survived through this meandering, it's worth considering what legal education should be. Perhaps it should still try to provide something different from the "minimum competence" required to pass the bar exam.
But as some law schools have departed from practices that may best benefit their graduates--particularly in high tuition costs; entrenched and inflexible standards; and declining control in the quality of admissions, retention, and graduation practices--it may be the case that we have forgotten what law school ought to be. Its purposes have been lost as we consider it as a kind of necessary rite of passage before one takes the bar exam. In this instrumental vein, distrustful of the operation of law schools, the accreditation process should look mostly at the outputs of graduates.
I don't think that's a welcome development, either on the accreditation end or on the telos of legal education. But it's perhaps the necessary evil that has come upon us, until either schools change their practices or the market improves dramatically. Even then, it will be hard to separate legal education from the bar exam, and that loss speaks more about why the ABA is still accrediting schools in the first place--or why state bars require legal education before taking the bar exam.