Let us begin with a story about the late Justice William J. Brennan. According to his law clerks,
[a]t some point early in their clerkships, Brennan asked
his clerks to name the most important rule in constitu-
tional law. Typically they fumbled, offering Marbury v.
Madison or Brown v. Board of Education as their answers.
Brennan would reject each answer, in the end providing
his own by holding up his hand with the fingers wide
apart. This, he would say, is the most important rule in
constitutional law. Some clerks understood Brennan to
mean that it takes five votes to do anything, others that
with five votes you could do anything.1
Another version of the tale resolves the ambiguity in Brennan's explanation: “Five votes can do anything around here.”2 Hence what is now sometimes called “Justice Brennan's famed 'rule of five.'“3
My immediate interest in this story lies not so much in which meaning Justice Brennan intended as in the meaning that some of his clerks attributed to him, which I shall call the “strong” version of the Rule of Five: with five votes you can do anything “around here.” The context of the remark was, of course, the Supreme Court as a decision-making body, even if Brennan put his question—interestingly—in terms of the most important rule in constitutional law, not in terms of the Court's institutional power. A five-justice majority on the Court, the strong Rule of Five asserts, can do anything, at least in deciding constitutional-