Politics is to politician as law is to what?
A hypernym for lawyer/judge/law student, etc.
Edit: Not only in the legal system, anyone practicing or researching the subject. Maybe politics wasn't the best example.
The Bar usually refers to "lawyers or the legal profession" (see noun sense 14 in wiktionary) but I've occasionally seen it applied to the judiciary as well. (The judiciary is "The court system and judges considered collectively, the judicial branch of government".)
Some of my law textbooks referred to such people as Jurisprudents:
— n 2. a jurisprudent person