Chevron Step Two\u27s Domain

An increasing number of judges, policymakers, and scholars have advocated eliminating or narrowing Chevron deference—a two-step inquiry under which courts defer to federal agencies’ reasonable interpretations of ambiguous statutes the agencies administer. Much of the debate centers on either Chevron’s domain (i.e., when Chevron should apply at all) or how courts ascertain statutory ambiguity at Chevron’s first step. Largely lost in this debate on constraining agency discretion is the role of Chevron’s second step: whether the agency’s resolution of a statutory ambiguity is reasonable. Drawing on the most comprehensive study of Chevron in the circuit courts, this Article explores how circuit courts have applied Chevron step two to invalidate agency statutory interpretations. In doing so, it identifies three separate approaches that merit further theoretical and doctrinal development: (1) a more-searching textualist or structuralist inquiry into the statutory ambiguity in light of the whole statute; (2) an enhanced purposivist or contextualist inquiry; and (3) an inquiry into an agency’s reasoned decisionmaking similar to arbitrary-and-capricious review under the Administrative Procedure Act