Unless your daughter has a lawyer-client relationship with her stepmother, she doesn't have an ethical complaint.
That is not to say that any misbehavior or criminal activity by a lawyer can't result in disciplinary action, but it usually has to have something to do with the practice of law. In most states I'm familiar with, a lawyer convicted of a felony is automatically disbarred and a lawyer committing a misdemeanor may have to explain his behavior satisfactorily to the Character and Fitness Committee. They usually take a closer look at candidates applying for the bar before they've been admitted and certain things involving dishonesty or moral turpitude (plagarism charges, resume puffery) may be problems.
But back to your daughter, unless she's in the hospital or suffered serious enough injuries for the stepmother to be charged with assault, you're barking up the wrong tree here.
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I agree with my colleague. If the stepmother was violent, the answer to her behavior is the same as it would be for anyone else, call the police and file a complaint. In many states, if an attorney is convicted of a certain level of crime, the bar will become involved at that point. But unless and until that occurs, or unless your daughter was a client of the stepmother, there is no basis for an ethics complaint here.
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