As is usual when a vacancy comes up on the Supreme Court, some people suggest that the President nominate someone other than a sitting judge, to give the Court some more diverse experiential background. That's not such a bad idea -- the Court could benefit from having some people who know what it's like to run for office, manage a large law firm, or run a government agency.
But what about the perennial suggestion for a nonlawyer Justice? Now that, I would say, goes too far.
The suggestion that we put a nonlawyer on the Supreme Court seems to be based on the notion that the Supreme Court just makes up constitutional law anyway, so why couldn't a lay person make it up just as well as a lawyer?
Quite apart from the fact that I'd like to think that there's more to constitutional law than that, I think people who suggest putting a nonlawyer on the Court are forgetting that the big-deal con law cases that they have in mind make up just a small percentage of the Supreme Court's docket.
Even if you think that the Supreme Court just makes up the answers to questions about abortion, affirmative action, right to die, and other big-deal constitutional issues, what is your nonlawyer Justice going to do with questions like, "can the plaintiff in a diversity case add a claim against a non-diverse third-party defendant impleaded by the original defendant?"
That kind of question actually takes up a pretty substantial percentage of the Supreme Court's time. Even if you regard big-deal con law cases as being in a separate category, I don't think nonlawyers would do such a great job with the rest of the Court's docket.