This is open to the objection that a free system depends on creating and sharing knowledge of which lawyers are competent. But knowledge is a public good, so it tends to be under produced by free market systems. You hope to find a competent lawyer for your own case, but are disappointed to find that lawyer ratings are hard to come by. Here are three alternatives:

Status Quo: Government attempts to checks who is competent with a bar exam and a disciplinary tribunal for lawyers. The results are not just published they are enforced. If you have an official black mark against your name, you are forbidden from practicing.

Information Only: Government attempts to checks who is competent with a bar exam and a disciplinary tribunal for lawyers. The results are merely published, not enforced. If you don't trust the Government, you can still chose to be represented by a lawyer with a Government black mark against the name.

Taxation funds competing certification authorities: The Government funds Bar-A, Bar-B, Bar-C. That results in inefficient duplication. It offers the public weak protection. A lawyer who fails the Bar-A exam can still pass the Bar-B exam and get to practise. On the other hand, the Bar council is no longer a power honey pot attracting wasps. If Bar-A abuses its authority, the public will lose confidence and trust Bar-B.

There are untested alternatives in the space between raw government power leading to abuse and market mechanisms under producing public goods.