I suspect that many of them are not aware of who has a J.D. and who does not. See if you can tell which sections have the luster that can only be provided by a law school education. You can play the same game with the guides we have on U.S. legal research topics. The students also pay attention when Peggy tells them a story from when she was a librarian at a big law firm downtown and saw that side of legal practice. I don't have that big firm experience, so Peggy can offer the students something I can't.
Legal education can contribute to excellence in reference librarianship.
However, it is neither necessary nor sufficient.