The Felix Frankfurter quotation at the start of the novel, "The due process clauses ought to go," is taken from an unsigned editorial entitled "The Red Terror of Judicial Reform," written by Frankfurter for The New Republic, October 1, 1924. It is reprinted in Law and Politics: Occasional Papers of Felix Frankfurter, 1913-1938, Archibald MacLeish and E. F. Prichard, Jr., editors, p. 16 (1971). Here is the full quotation: 

An informed study of the work of the Supreme Court of the United States will probably lead to the conclusion that no nine men are wise enough and good enough to be entrusted with the power which the unlimited provisions of the due process clauses confer. We have had fifty years of experiment with the Fourteenth Amendment, and the centralizing authority lodged with the Supreme Court over the domestic affairs of forty-eight widely different states is an authority which it simply cannot discharge with safety either to itself or to the states. The due process clauses ought to go. It is highly significant that not a single constitution framed for English-speaking countries since the Fourteenth Amendment has embodied its provisions. And one would indeed be lacking in a sense of humor to suggest that life, liberty, or property is not amply protected in Canada, Australia, South Africa. By eliminating this class of cases the Supreme Court would really be relieved of a contentiously political burden. It would free itself to meet more adequately the jurisdiction which would remain and which ought to remain. The Court would still exercise the most delicate and powerful function in our dual system of government. To discharge it wisely, it needs a constant play of informed criticism by the professional as well as the lay press. This, in turn, implies an alertly progressive bar, the product of a lively spirit of legal education at our universities, and a public opinion trustful of the workings of our judiciary because the trust is justified by its exercise.