Empirical scholars typically model the judicial hierarchy in terms of a principal-agent relationship in which the Supreme Court, the principal, sets policy and the lower federal courts, as agents, must faithfully implement that policy. The law is a signal—the means by which the Court communicates its preferences. This Article argues instead for recognizing the law as an independent normative force. Empirical scholars fail to take seriously the role of law because they reject as implausible formalistic accounts of its operation. This Article advances a more nuanced account of how law shapes the decisionmaking environment of the lower federal courts, one that focuses on the presence of discretion. It explores how different types of discretion afford distinct types of power over lawmaking and case outcomes, and how that discretionary power is allocated between district and appellate courts. Paying attention to discretion suggests features of the judicial hierarchy that are commonly overlooked in principal-agent models. For example, judges’ goals, and therefore their strategies, will vary depending upon whether they seek to influence law development or merely to shape case outcomes. The Article also questions the normative assumption, implicit in principal-agent models, that lower federal courts should decide cases in accordance with the policy preferences of the Supreme Court. Because judges inevitably have discretion when applying the law, a norm of compliance with superior court precedent does not necessarily require lower courts to follow the policy preferences of the Supreme Court. The reasons judicial discretion exists, such as allocating power within the judicial hierarchy, may argue against such a centralization of power in the Supreme Court.