The norm of consensus on the US Supreme Court

For four decades scholars have sought to explain the rise of dissensus on the U.S. Supreme Court. While the specific explanations they offer vary, virtually all rest on a common story: during the nineteenth (and into the twentieth) century, the Supreme Court followed a norm of consensus. That is, the justices may have privately disagreed over the outcomes of cases but masked their disagreement from the public by producing consensual opinions. The problem with this story is that its underlying assumption lacks an empirical basis. Simply put, there is no systematic evidence to show that a norm of consensus ever existed on the Court. We attempt to provide such evidence by turning to the docket books of Chief Justice Waite (1874-1888) and making the following argument: if a norm of consensus induced unanimity on Courts of by-gone eras, then the norm may have manifested itself through public unanimity in the face of private conference disagreements. Our investigation, which provides systematic support for this argument and thus for the existence of a norm of consensus, raises important questions about publicly unified decision-making bodies, be they courts or other political organizations.