Auer deference holds that reviewing courts should defer to agencies when the latter interpret their own preexisting regulations. This doctrine relieves pressure on agencies to undergo costly notice-and-comment rulemaking each time interpretation of existing regulations is necessary. But according to some leading scholars and jurists, the doctrine actually encourages agencies to promulgate vague rules in the first instance, augmenting agency power and violating core separation of powers norms in the process. The claim that Auer perversely encourages agencies to “self-delegate”—that is, to create vague rules that can later be informally interpreted by agencies with latitude due to judicial deference—has helped to persuade the Supreme Court to...