Ethics

Article here.  The LSATs aren't de jure required by the ABA accreditation standards, but are pretty close to de facto required.  It'll be interesting to see if Michigan's experiment loosens the grip of LSATs on the admissions process.  The de facto requirement, the effect of LSATs on USN&WR rankings, and the "echo chamber" produced by the rankings all combine to produce an iron cage that stifles law school innovation and experimentation.

As I recall, any law school not using the LSATs must place a writing in the school's files justifying each particular admission.  Michigan's experiment is narrowly limited to students with an outstanding GPA from an outstanding undergraduate school, so their justifications will have some heft to them.