If the ABA made it a requirement that at least 90% of law school graduates must pass the bar, would most law schools not exist?

Answer 1

Very few law schools would be able to maintain a 90% pass rate; however, you must take into account the large number of law school graduates who choose not to take the bar at all.

In this hypothetical world law schools would admit far fewer applicants in the fear that their students might lower their pass rates.