Forty-three times since 1954—approximately twice every three Terms—the Supreme Court has heard a case in which no party argued one side of the issue before the Court, generally because the party who prevailed in the lower court refused to defend its victory below. When faced with this unusual, nonadversary posture, the Court has tapped an attorney to brief and argue the case as an amicus curiae in support of the orphaned argument. This practice raises a number of questions: First, at the most basic descriptive level, why has it been necessary? If the respondents themselves did not wish to defend their victories below, then whom were the appointed amici representing? Second, did these uncontested cases run afoul of Article III’s limitation of federal jurisdiction to “cases” and “controversies,” or the American tradition of adversarial litigation? And third, even if the invitations were constitutionally permissible, was it prudent for the Court to spend its scarce certiorari grants on them rather than waiting for more traditional cases to present the same issues?

This Note explores some answers to those questions. It identifies four broad categories into which these cases fall, based on the reasons the appointment of an amicus was deemed necessary, and evaluates each against the principal goals of the adversary system. Often the Court’s role as a neutral adjudicator of disputes is aided by the assistance of an amicus curiae who can represent the lower court’s position on an issue of independent interest to the courts, such as subject matter jurisdiction. But there are some questions that the Court is not empowered to answer unless they are contested, such as issues and arguments that the parties are entitled to waive—and sometimes have actively chosen to waive—or those that have become moot on appeal. To the extent appointing an amicus enables the Court to resolve legal questions that are not squarely presented by a live controversy, the practice itself should be abandoned, lest the Court appear to be reaching out to address issues that do not arise organically. Even where a live controversy does remain, it may be imprudent to choose less-than-fully-adversarial cases as vehicles to set national precedent. The Note concludes by proposing three criteria to determine the propriety of inviting an amicus to argue an unrepresented position, and finds that under those criteria, fifteen of the forty-three appointments were probably ill-advised.