Whose discretion is this anyway? Judicial review of agency statutory interpretations in federal courts of appeals: A comparative analysis

The U.S. federal courts review on appeal actions of federal regulatory agencies. This study undertakes a comparative analysis of the approaches to judicial review of agency statutory interpretation in all thirteen federal courts of appeals. Using a database of 1,360 cases decided by these courts over a period of time of 10 years, I verified the validity of previous models proposed in the literature for explaining judicial behavior, while proposing my own set of hypotheses. Whether a court will reject (i.e., reverse or remand) an agency statutory interpretation is a function of: (1) political factors---political convergence between the ideology of the panel and the political direction of agency's interpretation, and political salience of the issue; (2) legal precedent---Supreme Court's caseow, i.e., Chevron and recent cases, such as Christensen and Mead; (3) factors related to the courts---annual overall caseload per judge, annual administrative caseload, panel's previous work experience with a federal agency; (4) factors related to the agency---type of agency and the frequency of that agency's presence before federal courts of appeals; (5) factors related to the case before the court---the technicality of the issue, the divisiveness of the court's opinion, the type of party challenging the agency interpretation, presence of amicus briefs; (6) factors related to the district court's decision in the case. A Probit analysis tests a multivariate model of impact of these factors on the courts' decisions to reverse or affirm an agency interpretation. The results of the study support to a certain degree the findings of previous studies that stressed the role of political ideology and legal precedent in judicial decision-makings, but point out the significant influence of other factors as well. More specifically, my findings show that the success of an agency before the courts is influenced by political factors, Supreme Court's precedent, as well as by factors characterizing the courts, the agency, the case, and the district court's decision.