Walter notes how far to the right the court has moved in recent years, and plenty of evidence backs him up. If you look at a standard ranking of justices by how conservative their votes are (and I am looking at the third column on Page 111 of The Behavior of Federal Judges, a recent book by by Lee Epstein, Bill Landes, and our Breakfast Table interlocutor Richard Posner), you will see that Thomas, Alito, Scalia, and Roberts are the second-, fourth-, fifth-, and 11^th-most conservative justices since 1937. With Walter, I suspect that Alito will rise to the top when the data set is extended beyond 2009. O’Connor is No. 14, so it wouldn’t be surprising if Walter were right that her replacement with Alito moved the court further to the right.

This rightward movement has been a significant source of unhappiness among liberals, and many of them accuse the conservative justices of being ideologically motivated. Now of course they are; everyone knows that Supreme Court justices are at least in part ideologically motivated. Statistical analysis by Epstein and many other political scientists and law professors have established beyond doubt that you can predict the votes of a Supreme Court justice in large part (but not completely) based on the party of the appointing president and other signals of the ideology of the justice at the time that he or she was appointed. But that, of course, means that liberal justices are ideologically motivated as well.

This makes it a lot harder to criticize the current court for being out of line. The standard liberal criticism is that it (as well as its predecessor, the Rehnquist Court) has eroded precedents from the Warren Court era of the 1950s and 1960s. The Warren Court established many of the constitutional norms that we take for granted today—in areas of civil rights, privacy, voting rights, First Amendment rights, and the rights of criminal defendants, among others. But the Warren Court was even more ideologically extreme than the current court—just in the opposite direction. The table I am looking at ranks Marshall, Goldberg, Douglas, Brennan, and Fortas—Warren Court stalwarts from the 1960s—as the five most liberal justices since 1937. Warren himself was the eighth. Once we understand the Warren Court’s position in the historical record, it becomes harder to say that the current court is ideologically out of line. At a minimum, it is not sufficient criticism to say that it refuses to uphold precedents of the Warren Court, which of course ignored the precedents of its predecessors. We need some nonhistorical baseline for evaluating justices, and when we search for one, we, as much as the justices we criticize, seem to fall back on ideological priors.

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