Buchbesprechung Giuseppe Franco Ferrari (ed), Judicial Cosmopolitanism. The Use of Foreign Law in Contemporary Constitutional Systems, Leiden/Boston: Brill Nijhoff 2019, XIV + 901 S, 250,00 €/300,00 $, ISBN 978-90-04-29759-3

During the last decades, it became more and more salient that comparative legal reasoning is not only a scholarly exercise, but also conducted by constitutional courts all across the world, hence deserving continuous academic attention.¹¹The author is part of the European Constitutional Court Network (ECCN) project funded by the go!digital programme of the Austrian Academy of Sciences (ÖAW), which examines the citation practice of constitutional courts including the European Court of Justice and the European Court of Human Rights. The programme is led by Ass.-Prof. Dr. Lisa Lechner (University of Innsbruck) and Prof. Dr. Lando Kirchmair (Bundeswehr University Munich and University of Salzburg). The author would like to thank the latter for his valuable comments and suggestions. Guiseppe Franco Ferrari’s edited volume sheds light on the practice of constitutional courts using legal comparison in their respective adjudication. In an extended introduction (1–26), Ferrari explores judicial constitutional comparison and its varieties. Firstly, the growth of constitutional comparison is retraced by placing the book in the plethora of existing literature²²For example, Michal Bobek, Comparative Reasoning in European Supreme Courts (2013); Janneke H. Gerards/Joseph W. A. Fleuren, Implementation of the European Convention on Human Rights and of the judgments of the ECtHR in national case-law: a comparative analysis (2014). and by juxtaposing the development in the United States and Europe, including the spillover from Western to Eastern Europe from the mid-1990s onwards. Secondly, Ferrari provides explanations for the resort to foreign material: i) the growth in the number of legal systems and in written and entrenched constitutions, ii) a qualitative transformation of constitutionalism with fundamental rights as its leitmotiv, iii) networks between judges, and iv) increased accessibility of academic and jurisprudential sources. In the third and fourth part of the introduction, several taxonomies on how to classify legal systems are being perused.³³ Basil Markesinis/Jörg Fedtke, Judicial Recourse to Foreign Law, A New Source of Inspiration? (2006) 23 ff; Ernest A. Young, Foreign Law and the Denominator Problem, Harvard Law Review 2005, 148 (151, 153); Steven Calabresi/Stephanie Dotson Zimdahl, The Supreme Court and Foreign Sources of Law: Two Hundred Years of Practice and the Juvenile Death Penatly Decision, William & Mary Law Review 2005, 743 (884); David Zarring, The Use of Foreign Decisions by Federal Courts: An Empirical Analysis, Journal of Empirical Legal Studies 2006, 297; Stephen Yeazell, When and How U.S. Courts Should Cite Foreign Law, Constitutional Commentary 2009, 59; Stephen A. Simon, The Supreme Court’s Use of Foreign Law in Constitutional Rights Cases, Journal of Law and Courts 2013, 279; Ulrich Drobnig, Die Nutzung der Rechtsvergleichung in der Deutschen Rechtsprechung, Rabels Zeitschrift für ausländisches und internationales Privatrecht 1986, 610; Pier Giuseppe Monetari/Alessandro Somma, Alien in Rome. L‘uso del diritto comparato come interpretazione analogica ex art. 12 preleggi, Foro it 1998, Part V, col 47; Mads Andenas/Duncan Fairgrieve, Intent on making mischief: seven ways of using comparative law, in Pier Giuseppe Monetari (ed) Methods of Comparative Law (2012) 25. Fifthly, there follows