You don’t get to declare what is unethical by adding the sentence “Period.” after your claim. Ethics is a matter of opinion; I believe that knowingly aiding violent criminals is wrong; if you feel otherwise, that’s just like, your, opinion, man.
The standards of ethics they are checked against are not yours or mine, they are the rules they agreed to. To pretend like ethics aren't a thing for lawyers is surprisingly uninformed for HN.
I bet you change your mind about the ethics of having a lawyer represent you.
Unless you are the sort of person that claims that reality is just an opinion, too, in which case you should also study formal philosophy.
Ethics is a matter of philosophy, which has a bit more going for it than just being composed of raw, uneducated opinion.
You are thinking of morals. That is a matter of opinion