The practice of appointing an individual to serve as chief justice is grounded in tradition; while the Constitution mandates that there be a chief justice, it is silent on the subject of how one is chosen and by whom. There is no specific constitutional prohibition against using another method to select the chief justice from among those justices properly appointed and confirmed to the Supreme Court. Constitutional law scholar Todd Pettys has proposed that presidential appointment of chief justices should be done away with, and replaced by a process that permits the justices to select their own chief justice.[4]