Since the Supreme Court's 1984 Chevron decision, the primary responsibility for interpreting federal statutes has increasingly resided with federal agencies in the first instance rather than with the federal courts. In 2005, the Court reinforced this approach by deciding National Telecommunications Ass'n v. Brand X Internet Services, which legitimized the agency practice of interpreting federal statutes in a manner contrary to the federal courts' established interpretation, so long as the agency interpretation is entitled to deference under the well-established Chevron standard. In essence, agencies are free to disregard federal court precedent in these circumstances. This Article analyzes the question left unanswered by Brand X - specifically, whether agencies can also ignore federal court interpretations of federal statutes when the agency's interpretation is not entitled to Chevron deference - and argues, based on consideration of constitutional theory and practical repercussions, that agencies may only do so in extremely limited circumstances where there is substantial justification. This Article reviews the Equal Employment Opportunity Commission's policy of ignoring federal precedent in order to illustrate the damage caused by an unjustified policy