In the region of middle axioms: judicial dialogue as wide reflective equilibrium and mid-level principles

This article addresses the use of foreign law in constitutional adjudication. We draw on the ideas of wide reflective equilibrium and public reason in order to defend an engagement model of comparative adjudication. According to this model, the judicial use of foreign law is justified if it proceeds by testing and mutually adjusting the principles and rulings of our constitutional doctrines against reasonable alternatives, as represented by the principles and rulings of other reasonable doctrines. By this, a court points to a wide reflective equilibrium, justifying its own interpretations with reasonable arguments, i.e. arguments that are acceptable from the perspectives defined by other constitutional doctrines, as endorsed by other courts. The point of a judicial engagement of this sort is to work out an overlap between different, reasonable, doctrines in the judicial forum, as part of a liberal forum of public reason. Here, the exercise of public reason filters out the premises of comprehensive doctrines so as to leave us in the region of an overlapping consensus: a region of mid-level principles that can be shared, notwithstanding the fact of legal pluralism.We gratefully acknowledge the support of the Spanish government, through the research grants DER2016-80471-C2-1-R (AET) and Ramon y Cajal RYC-2012-12175, of the Generalitat of Catalonia, through the research grant 2017 SGR 00823, and of the Alma Mater Studiorum-Università di Bologna, through the CRUI-CARE Agreement. We are grateful to colleagues and friends for comments that greatly improved this work. Thanks in particular to Marcelo Alegre, Samantha Besson, Giorgio Bongiovanni, Damiano Canale, Corrado Caruso, Mathieu Carpentier, Carlos Esposito, Jordi Ferrer, Roberto Gargarella, Matthias Klatt, Mattias Kumm, José Luis Martí, Ezequiel Monti, Philip Pettit, Jahel Queralt, Angeles Rodenas, Carlos Rosenkrantz, Giovanni Sartor, Frederick Schauer, and Anna Stilz. Some of the ideas defended in this article have been presented in Barcelona, Bochum, Buenos Aires, Girona, Graz, Lisbon, Lucerne, and Princeton. We thank the organizers and audiences of those events for their feedback, and for helpful discussions. We are also extremely grateful to two anonymous reviewers and to the editors of Law and Philosophy for comments and suggestions that have greatly improved this work