I mean, the local Bar would have a lot to say about lawyers that don't do what the client tells them to do. And, at least in the Common Law system it is typical that lawyers will argue that guilty people are not guilty all the time. Like, the news is full of these types of cases. And the ethics of representing the guilty have been worked out pretty well by now; it's really necessary. Most Bar Associations are pretty strict and hand out disbarments all the time for scummy lawyers.