Who will be the next justice of the Supreme Court? What kind of person does that august institution need now?

Appointments to the Supreme Court are so profound and long-term a presidential legacy that they rank among the most influential of all constitutional acts of any chief executive. Because the merit-selection process has become one of the most testy issues faced by the Carter administration, Congress, the media and the public can be expected to give his first Supreme Court appointment a critical look.

No doubt, when the time comes, President Carter will be beseiged by special-interest organizations pressing him to appoint a woman, a black, a Jew, perhaps even a Bakkean WASP. Parochial, demographic balancing of Supreme Court justices has been the tradition. As if his decision will not be difficult enough, the president might want to consider another intriguing possibility: appointing a non-lawyer.

There is nothing in the Constitution, or in the Journal of the Federal Convention, indicating any requirement that Supreme Court justices - or any federal judges, for that matter - be lawyers. Madison's notes report that the only discussion about judicial qualifications at the constitutional convention concerned the question whether all federal judges should be land owners.

Having a learned non-lawyer as a Supreme Court justice could have a timely appeal. Recent surveys have shown that large segments of the American public feel alienated from the legal system. Such an appointment might help de-mystify the law and the judicial process.

The idea that non-lawyers can cope with important and complex legal issues is not unprecendented. Only 54 percent of the members of Congress are lawyers; thus, almost half of the people who write the country's laws are not lawyers. Most of our presidents have not been lawyers; and they have daily confronted the most vexing and confounding issues. They have come from varied backgrounds: a university president, an engineer, a general, several legislators; the only lawyer president in recent times was almost impeached for violating the law.

Would there be suitable lay candidates for the Supreme Court? Would they be treated like second-class citizens by the rest of the court, or by the public? I think the answers are yes, and no.

Would a literate generalist such as a Walter Lippmann or a Ralph Bunche have made a good and respectable Supreme Court justice? How profound an opinion on capital punishment Hannah Arendt might have authored. Would John Galbraith not be able to write a superb antitrust opinion? Would Dr. Robert Coles or John Gardner or Margaret Mead be able to comprehend the vital human issues brought before the court, to grapple intellectually with competing social needs? And who thinks Hubert H. Humphrey would have been submerged and embarrassed by his lawyer colleagues on the court?

Think about the quality of the court's important literature. Though they write about the most dramatic subjects and the most weighty issues, most Supreme Court justices have been dreary writers. Clear and literate opinions like the ones of Oliver Wendell Holmes (who never practiced) and Robert H. Jackson (who didn't go to law school) and William O. Douglas (whose illustrious prior career was in governmetn and teaching) were exceptions to a general rule of dull writing. How delightful it would be to read an elegant opinion on any subject if it were written with the adept, skillful (non-laywer's) hand of a Loren Eisley or an Alfred Friendly. One of the best, most insightful books I've ever read about courts and legal systems was (non-lawyer) Sybille Bedford's "The Faces of Justice." If plucking a Felix Frankfurter from academia resulted in a mighty justice, why would not the same have been so if the professor had been T.V. Smith or Alexander Meikeljohn?

It should not be shocking if Jimmy Carter appointed an estimable scholarwriter to the Supreme Court. Court rode into office on the wave of public resentment of establishment Washington, in a populist climate, at a time when the bar is held in low repute. The idea of a non-lawyer member of the court should not appall Jimmy Carter; he would be a good justice himself.