By appointing four justices Truman made the Supreme Court his own. It was, to be sure, still the New Deal court that Roosevelt had shaped, but with an enormous difference, one that bears directly on the subject of McCarthyism.
The New Deal court gave a revolutionary interpretation to the Constitution. On the one hand, it withdrew the court's historical protection of economic liberty, allowing the democratic system, or majority rule, to regulate economic liberty as it saw fit. On the other hand, it extended its protection to civil liberties as laid down in the Bill of Rights on the grounds that civil liberties occupied a privileged status in the law, that dissentient groups and individuals, however unpopular their views, had rights that the majority could not violate. During World War II, the New Deal court did not stand in the government's way on civil liberties or any other issues, but no sooner was it over that the court resumed its reading of the Constitution.
Within a few years, however, three of Roosevelt's arch civil libertarian justices died--Harlan F. Stone, Frank Murphy, and Wiley B. Rutledge-- and were replaced by men of a very different temper--Fred M. Vinson, Sherman Minton, and Tom C. Clark. What distinguished the latter three was their utter mediocrity. Though justices almost invariably reflect the beliefs of the president who chooses them, the important question is what kind of people are they. No one can deny the greatness of John Marshall, partisan Federalist that he was (did Jefferson detest anyone more?), which is not to say that the views of the Truman justices should be attributed to