Re-evaluating Judicial Review in Korea: Why Loper Bright’s :Challenge to Deference Demands Reform of the Judgment Margin Doctrine

The central argument of this paper has been that the Korean judiciary’s deference model, through its own unique historical path, arrived at a functional destination nearly identical to that of U.S. Chevron doctrine. Consequently, the U.S. Supreme Court’s decision to abandon that destination in Loper Bright is not merely a comparative curiosity; it serves as a fundamental challenge to the stability of Korea’s own administrative rule of law, compelling a deliberate choice about its future path. The U.S. decision transforms the domestic Korean debate from a theoretical discussion into a matter of practical urgency, reframing the central question: no longer if Korea's deference model is tenable, but how it must be reformed. A path forward lies not in importing a new abstract theory, but in evolving judicial methodology toward a more structured, persuasion-based standard. A new methodology would require a two-part inquiry. First, courts must explicitly determine if a case truly involves the specialized, technical judgment that warrants a ‘margin of review’. For cases that meet the threshold, the judicial focus must then shift from a passive check for arbitrariness to an active assessment of the agency’s reasoning. This process creates a new standard of earned deference, where the administration must affirmatively persuade the court that its conclusions are justified by evidence and sound analysis. Adopting a more rigorous standard of review, however, presents significant institutional challenges. An intensive review process would place a substantial burden on the judiciary and demand a serious commitment to building judicial capacity, potentially through specialized training, improved systems for expert support, or even specialized administrative courts. Ultimately, Loper Bright elevates the debate beyond abstract legal doctrine. The real challenge for the Korean legal community is now one of political will: whether to undertake the difficult institutional reforms necessary to empower the judiciary as the ultimate guarantor of the rule of law. Korea’s answer will redefine the balance of power and the meaning of democratic accountability for years to come.