The Constitution requires that all legislators, judges, and executive officers swear or affirm their fidelity to it. The resulting practice, often called “the oath,” has had a pervasive role in constitutional law, giving rise to an underappreciated tradition of promissory constitutionalism. For example, the Supreme Court has cited the oath as a reason to invalidate statutes, or sustain them; to respect state courts, or override them; and to follow precedents, or overrule them. Meanwhile, commentators contend that the oath demands particular interpretive methods, such as originalism, or particular distributions of interpretive authority, such as departmentalism.
This Article provides a new framework for understanding the oath, its moral content, and its implications for legal practice. Because it engenders a promise, the oath gives rise to personal moral obligations. Further, the content of each oath, like the content of everyday promises, is linked to its meaning at the time it is made. The oath accordingly provides a normative basis for officials to adhere to interpretive methods and substantive principles that are contemporaneously associated with “the Constitution.” So understood, the oath provides a solution to the “dead hand” problem and explains how the people can legitimately bind their elected representatives: with each vote cast, the people today choose to be governed by oath-bound officials tomorrow. Constitutional duty thus flows from a rolling series of promises undertaken by individual officials at different times. As old officials give way to new ones, the overall constitutional order gradually evolves, with each official bound to a distinctive promise from the recent past. This process of gradual change is normally invisible because the oath also incorporates publicly recognized rules for legal change, or “change rules,” such as the Article V amendment process. As a result, the timing of an official’s oath becomes morally relevant only when a legal change has not complied with previously recognized change rules, such as in the case of a revolution. Finally, because promises, even constitutional promises, should sometimes be broken, the oath can illuminate the bounds of constitutional duty, including the role of stare decisis, and shed light on instances when the Constitution itself should be set aside.