prior probability

(Supreme Court judges, that is.) Neal Katyal, a law professor at Georgetown University, reports in this op-ed that there were no dissenting opinions in more than two-thirds of the cases decided by the U.S. Supreme Court last term. Here is an excerpt from Katyal’s essay:

For years, particularly after the 2000 election, talk about the Supreme Court has centered on its bitter 5-to-4 divisions. Yet it is worth reflecting on a remarkable achievement: The Court has agreed unanimously in more than 66 percent of its cases this term … The last year this happened was 1940 … Unanimity is important because it signals that the justices can rise above their differences and interpret the law without partisanship. The best illustration of this in the modern era is Brown v. Board of Education, in which the court unanimously declared racial segregation in education to be unconstitutional. When the justices forge common ground, it signals to the nation the deep-seated roots of what the court has said and contributes to stability in the fabric of the law.

Do you buy Katyal’s argument? After all, isn’t the decision in Brown v. Board of Education no less “political” than the Court’s nefarious decision in Plessy v. Ferguson? That is, isn’t the Supreme Court inherently a political court when deciding constitutional cases, regardless of the margin of the Court’s decisions? (We say “yes” because unlike baseball umpires (sorry Mr Chief Justice), who simply do their best to enforce the rules of the game, the judges on the Supreme Court actually get to make the rules!)