Law school is just a costly prelude. But the high cost of entering the market suppresses competitors and keeps the cost high. Many poor people are priced entirely out of the legal services market . If they do manage to pay for legal work done, it is with considerable sacrifice of other needs. Nor is bar membership a sufficient condition for competence.
Lawyers make many errors, as do practitioners in all fields of human endeavor.
No course of training or set of licensure requirements can eliminate error. The strongest disincentive to error is the harm it does to the person who commits it, and that disincentive is increased not one bit by the holding of a license. Benefits of a Free Market in Legal Services Competition gives consumers the widest range of options, keeps prices down, and motivates competitors to keep quality high enough to satisfy customers. As things now stand, people in need of legal assistance can either do it themselves or hire an attorney to do it. There is no middle ground, as there is in accounting, where one can hire someone who isn't a CPA if one so desires.