The judicial doctrine established by Chevron v. Natural Resources Defense Council, which compels courts to defer to agency interpretations of ambiguous statutes, faces a momentous challenge that could reshape administrative law. For decades, courts have been required to employ a two-step framework, first determining if Congress has directly addressed the issue at hand, and if not, deferring to any reasonable agency interpretation. This practice has been criticized for undermining the judiciary’s role in independently interpreting laws, a principle enshrined in the Administrative Procedure Act (APA). The present cases bring this tension to a head, questioning whether Chevron's deference is fundamentally at odds with the APA’s mandate that courts, not agencies, decide legal questions.

In a dramatic showdown, the fate of Chevron's deference is tested through a conflict over the Magnuson-Stevens Fishery Conservation and Management Act (MSA). The National Marine Fisheries Service (NMFS) imposed a rule requiring Atlantic herring fishermen to fund observers on their vessels, a mandate not explicitly authorized by the MSA. This rule has deeply impacted small fishing businesses, slashing their profits and sparking fierce legal battles. The courts have so far sided with NMFS, citing Chevron to uphold the rule despite the statute’s ambiguity. Now, as the Supreme Court takes on these cases, the very foundation of judicial deference to agency interpretations hangs in the balance, promising a dramatic re-evaluation of the balance of power between the judiciary and executive agencies.