On April 11, 2018, Arizona Governor Doug Ducey signed House Bill 2238, which eliminates the judicial doctrine commonly known as “Chevron deference.” One of the most well-known doctrines of administrative law, “Chevron deference” is named after the landmark case Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc., 468 U.S. 837 (1984).  In a nutshell, the Chevron deference doctrine provides that when a statute is ambiguous, courts must defer to the interpretation of the government agency in charge of administering the statute unless the agency’s interpretation is unreasonable.

House Bill 2238 eliminates Chevron deference through an amendment to A.R.S. § 12-910(E), which now states that “[i]n a proceeding brought by or against the regulated party, the court shall decide all questions of law, including the interpretation of a constitutional or statutory provision or a rule adopted by an agency, without deference to any previous determination that may have been made on the question by the agency.” The revised statute further provides that “[n]otwithstanding any other law, this subsection [A.R.S.  § 12-910(E)] applies in any action for judicial review of any agency action that is authorized by law.”  Notably, the new law excludes only one agency—the Arizona Corporation Commission—from its requirements.  A.R.S. § 12-910(G).

It remains to be seen whether Arizona House Bill 2238 will act as an additional limit on government regulation within the state.  For years, opponents of the Chevron deference doctrine have argued that it violates separation-of-powers principles by effectively granting government agencies with both executive and implicit judicial authority.  Consequently, do not be surprised if other state legislatures, and possibly the United States Congress, try to follow suit and legislatively overturn the doctrine and its progeny.