Justice Kennedy, in an interview with C-Span last year, described how communications among the justices actually work.
“Before the case is heard, we have an unwritten rule: We don’t talk about it with each other,” he said. If the rule is violated, “we send a memo to everybody about what we’ve talked about, because we don’t want little cliques or cabals or little groups that lobby each other before.”
“The first time we know what our colleagues are thinking is in oral arguments,” he said, “from the questions.” The justices next discuss the case at their private conference, now announcing tentative votes.
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The dean of a major law school can offer professors money, status, support for a pet project, help with housing, maybe even a job for a spouse. A Supreme Court justice has little more than a vote and such power of persuasion as flows from written reasoning.
“There is just more logrolling in the academy,” Professor Epstein said. “I have never observed in all my many years of reading the papers of the justices any evidence of logrolling.”
The Kennedy interview is here.