Comparative Law Research

Hester Swift has been Foreign and International Law Librarian at the Institute of Advanced Legal Studies, University of London, since 2007.

1. What is Comparative Law?

What is meant by comparative law? In the strict sense, it is the theoretical study of legal systems by comparison with each other, and has a tradition going back over a century. In recent years it has gained in practical importance for two reasons. The first is the increased globalization of world trade, involving the need to conduct business in unfamiliar legal systems. The second is the move towards harmonization of laws, under the auspices of bodies such as the Hague Conference on Private International Law and the European Union. More loosely, there are publications and internet resources that assemble legal materials from several jurisdictions, without necessarily undertaking comparisons, but they can be seen as tools of the trade for comparative lawyers.

2. Comparative Law, Conflict of Laws, and Unification / Harmonization of Law

These three topics are distinct but closely related. Conflict of laws, also referred to as private international law, concerns national or domestic legal rules which are applicable in situations involving the law of another jurisdiction. This may be another country or, in the case of federations, another state.

Unification of law is a process that grew out of the need to simplify conflict of law rules, often by international conventions, and has acted on both the national and international levels. The numerous uniform laws applicable in the United States, most notably the Uniform Commercial Code, are obvious examples.

There are two main sources of international uniform law. First, the Hague Conference on Private International Law first convened in 1893 and has prepared around 40 conventions on subjects such as international civil procedure, including enforcement of foreign judgments; family law, including marriage, protection of children and succession; and product liability.

Second, UNIDROIT, the International Institute for the Unification of Private Law, was set up in 1926 as an organ of the League of Nations but was re-established in 1940 under a new statute. About 60 nations are members. Its most notable convention is the Convention relating to a Uniform Law on the International Sale of Goods, 1964. Under ‘Instruments’ on the website, researchers may find a list of conventions organized by area of law (agency, capital markets, commercial contracts, contract farming, cultural property, factoring, franchising, international sales, international will, leasing, security interests, transnational civil procedure, and transport). Each category offers access to the relevant convention, official commentary, status, preparatory work, depository information, and relevant selected bibliography.

By the nature of its continuing development, the European Union is the center of harmonization activity in Europe. The main thrusts were for many years confined to private law, notably family law, contracts, sales, insurance, trusts and movable property; more recently, following the Treaty of Lisbon, the EU legislators have also moved into the area of criminal law.

European research centers looking at harmonization of law include:

• Commission on European Family Law (copy link into browser to open it), based at the University of Utrecht.; its monograph series European Family Law (EFL) is published by Intersentia.
• European Group on Tort Law in association with the European Centre of Tort and Insurance Law in Vienna. The Group is coordinated by Bernhard A. Koch of the
• University of Innsbruck and Miquel Martín Casals of the University of Girona.
• Study Group on a European Civil Code, chaired by Professor Christian von Bar at the University of Osnabrück.
• The European Law Institute, established in 2011 on the model of the American Law Institute; an independent body which works on European law generally.

A six-volume draft ‘Common Frame of Reference’ (DCFR) was produced by the Acquis Group and the Study Group on a European Civil Code:

von BAR, C. and CLIVE, E., eds., Principles, definitions and model rules of European private law: draft common frame of reference (DCFR). Oxford University Press, 2010.

A thorough exposition of the idea of a European Civil Code is contained in a collection of contributions from several legal scholars: Towards a European Civil Code, 4th edition, edited by Arthur Hartkamp and others. Kluwer Law International, 2010. Other works on European harmonization include:

• Bussani, M. and Mattei, U., eds. The common core of European private law. Kluwer Law International, 2002.
• Smits, J. The making of European private law: toward a ius commune Europaeum as a mixed legal system. Intersentia, 2002. (A translation of his Europees privaatrecht in wording)
• Micklitz, Hans-W., and Cafaggi, Fabrizio, eds. European private law after the Common Frame of Reference. Edward Elgar, 2010.
• Devenney, J. and Kenny, Mel B., eds. The transformation of European private law: harmonisation, consolidation, codification or chaos? Cambridge University Press, 2013.
• Colson, R. and Field, S., eds., EU criminal justice and the challenges of diversity: legal cultures in the area of freedom, security and justice. Cambridge University Press, 2016.
• Wieczorek, I., The legitimacy of EU criminal law. Bloomsbury Publishing, 2020.

For a much fuller discussion of harmonization/uniform law resources, see Duncan Alford’s Guide on the Harmonization of International Commercial Law (updated by Matthew Novak)on this website.

The world’s legal systems are a product of history, largely by conquest and colonization, but also in modern times by reasoned and deliberate adoption by one state of at least part of the legal framework of another. Two important examples are the modernization of Japanese and Egyptian law, and more recently the adoption of western models of commercial, financial and property law in the former socialist countries of Eastern Europe.

We can speak of “families” of legal systems, though increasingly the term “traditions” is being used, highlighting their historical development. The best-known distinction is that between the civil law and the common law traditions. Civil law systems have their foundations in Roman law, but are generally based on codifications produced in Europe in the 19th Century. The most important are the French Civil Code of 1804 and the German Civil Code of 1900. Each was the result of long and careful study by appointed commissions, but they are founded on differing traditions and theory.

Traditional classifications offered by the two classic writers on comparative law (see Books and Journals, below) are:

DAVID

• Romano-Germanic
• Socialist (more recently Russian)
• Common law
• Religious/philosophical: Islamic, Indian, Far Eastern, African/Madagascan

ZWEIGERT and KÖTZ

• Romanistic
  Germanic
  Nordic
• Anglo-American
• Far Eastern
• Religious: Islamic, Hindu

More recently there has been increasing interest in customary (or chthonic) law. Glenn (see below) gives a new list with a new emphasis: Chthonic, Talmudic, Islamic, Hindu, Asian, Civil law and Common law.

Another relatively new object of study is the mixed jurisdiction, where elements of more than one system are in operation. Examples are Louisiana, Quebec, Scotland, South Africa, and Sri Lanka. Palmer (see below) called mixed jurisdictions the “third legal family,” after common law jurisdictions and Roman-German jurisdictions.

Mattei has proposed a classification into three categories based on the principal source of legal norms: the rule of professional law, rule of political law and rule of traditional law (Mattei, U., ‘Three patterns of law: taxonomy and change in the world’s legal systems,’ (1997) 45 American Journal of Comparative Law 5).

In the first part of this article, I shall mention substantive comparative law sources, and in the second part sources that collect legal materials from many jurisdictions.

3. Books and Journals

3.1. Books

The Elgar Encyclopedia of Comparative Law, edited by Jan Smits,provides an overview of the subject; the second edition was published by Edward Elgar in 2012 and it is available in print or online format.

• The main classic European theoretical works on comparative law are: David, R., Jauffret-Spinosi, C., and Gore, M., Les grands systèmes de droit contemporains, 12e éd. Paris, Dalloz, 2016. The book has been translated into numerous languages. An English version of the 6th edition of 1974 was published by Sweet and Maxwell as Major legal systems in the world today, 3rd edition in 1985 (out of print).
• Zweigert, K. and Kötz, H., Einführung in die Rechtsvergleichung, 3e Aufl. Tübingen, Mohr, 1996. English translation: Introduction to comparative law, translated from the German by Tony Weir. Oxford, Oxford University Press, 1998.

The seminal British author was Harold C. Gutteridge. The second edition of his Comparative law, originally published by Cambridge University Press in 1949, was reprinted by Wildy in 1974; Cambridge reprinted the first edition (1946) in December 2015.

In the United States, the study of comparative law was pioneered by Rudolf Schlesinger. His Comparative law: cases, text, materials, first published in 1950, is now in its 7th (2009) edition and available from West Academic under the title Schlesinger’s comparative law. While at Cornell University, Schlesinger contributed to the discussions around the drafting of the U.S. Uniform Commercial Code.

Of similar standing is Arthur T. von Mehren, whose work, The civil law system: cases and materials for the comparative study of law appeared in 1957. A second edition, with James R. Gordley, was published in 1977 by Little, Brown.

Other titles include:

• Breda, V., ed. Legal transplants in East Asia and Oceania,Cambridge University Press, 2019.
• De Cruz, P. Comparative law in a changing world, 3rd. Routledge-Cavendish, 2007.
• Glendon, M., et al, Comparative legal traditions: text, materials, and cases on western law, 4th ed. West Academic, 2015.
• Glenn, H P. Legal traditions of the world: sustainable diversity in law, 5th ed. Oxford University Press, 2014 (1st edition gained the Canada Prize, International Academy of Comparative Law, 1998).
• Harding, A. and Örücü, E. (eds.) Comparative law in the 21st Century. Kluwer Law International, 2002.
• Legrand, P. and Munday, R. (eds.) Comparative legal studies: traditions and transitions. Cambridge University Press, 2003.
• Menski, W., Comparative law in a global context: the legal systems of Asia and Africa, 2nd ed. Cambridge University Press, 2006.
• Merryman, J.H. and Pérez-Perdomo, R. The civil law tradition: an introduction to the legal systems of Europe and Latin America, 4th ed. Stanford University Press, 2018.
• Palmer, V., ed., Mixed jurisdictions worldwide: the third legal family. 2nd ed., Cambridge University Press, 2012.
• Riles, A. Rethinking the masters of comparative law. Hart Publishing, 2001.
• Varga, C. European legal cultures.Dartmouth Publishing, 1997.
• Zimmermann, R. Mixed legal systems in comparative perspective: property and obligations in Scotland and South Africa. Oxford University Press, 2003.
• Zimmermann, R. and Reimann, M. The Oxford handbook of comparative law, 2nd ed.,Oxford University Press, 2019.

3.2. Journals

• African Journal of International and Comparative Law / Revue africaine de droit international et comparé. 1989- (published with the approval of the African Society of International and Comparative Law).
• American Journal of Comparative Law 1952 – (American Society of Comparative law)
• Asian Journal of Comparative Law 2006 – (Asian Law Institute)
• Boletín Mexicano de Derecho Comparado 1948- (Universidad Nacional Autónoma de México) (open access from 1968)
• Annuario di Diritto Comparato e di Studi Legislativi / Yearbook of Comparative Law and Legislative Studies (Edizioni Scientifiche Italiane, on behalf of the University of Sannio and University of Naples “Federico II”) 1927 –
• Comparative and International Law Journal of Southern Africa 1968 – (University of South Africa) (open access to 2005/06)
• Comparative Law Yearbook of International Business 1978- (formerly Comparative Law Yearbook). (Center for International Legal Studies, Salzburg)
• European Journal of Comparative Law and Governance(formerly Electronic Journal of Comparative Law) 1997- (Netherlands Comparative Law Association / Netherlands Institute for Law and Governance); open access up to 2011
• International and Comparative Law Quarterly 1952- (British Institute of International and Comparative Law)
• Ius Comparatum 2020 – (International Academy of Comparative Law), open access
• Journal of Comparative Law 2006- (Association for Comparative Legal Studies).
• Oxford University Comparative Law Forum2000- An open access journal edited by members of the Oxford Law Faculty.
• Rabels Zeitschrift für ausländisches und internationales Privatrecht 1927- (Max-Planck Institut für ausländisches und internationales Privatrecht)
• Revue de droit international et de droit comparé1949- (originally from the Institut belge de droit comparé)
• Revue internationale de droit comparé 1949- (Société de Législation Comparée) (open access on Persée to 2016)
• Scientia Iuridica : Revista de Direito Comparado Português e Brasileiro1951–(Universidade do Minho)
• Uniform Law Review / Revue de Droit Uniforme 1973 – (International Institute for the Unification of Private Law (UNIDROIT); amalgamates the two series Jurisprudence de droit uniforme and Unification du droit).
• Zeitschrift für vergleichende Rechtswissenschaft (Journal of Comparative Jurisprudence) 1878-

A more extensive list of comparative law journals has been compiled by Teresa Miguel and others: “Comparative Law: Academic Perspectives”, Appendix A, in The IALL International Handbook of Legal Information Management, Danner, R. A., and Winterton, J., (eds.), Ashgate, 2011 (open access version available from Yale Law School Legal Scholarship Repository).

4. Organizations and Research Institutes

The International Academy of Comparative Law, founded at The Hague in 1924, organizes the International Congress of Comparative Law, which takes place every four years. It produces general and national reports, the national reports being prepared by national committees. The reports are issued by various publishers, usually in the respective country (for example, Belgian national reports are usually published by Bruylant/Larcier). Publication details of recent reports appear on the Academy’s website.

4.1. Selected Organizations and Institutes by Country

• Argentina: Asociación Argentina de Derecho Comparado, 1946; Instituto de Derecho Comparado ‘Enrique Martínez Paz’, Academia Nacional de Derecho y Ciencias Sociales de Córdoba.
• Australia: Centre for Comparative Constitutional Studies, 1987, and Institute for International Law and the Humanities, 2005 (successor to the Institute for International and Comparative Law, established in 1999) University of Melbourne; Centre for Public, International and Comparative Law, 2003, University of Queensland.
• Austria: Österreichische Gesellschaft für Rechtsvergleichung, 2002; Institut für Europarecht, Internationales Recht und Rechtsvergleichung, University of Vienna.
• Brazil: Instituto de Direito Comparado Luso-Brasileiro, 1981.
• Canada: Institute of Comparative Law, 1965, McGill University; Paul-André Crépeau Research Centre for Private and Comparative Law (formerly the Quebec Research Centre of Private and Comparative Law), 1975, McGill University; Canadian Association of Comparative Law; Association Québécoise de Droit Comparé, 1960.
• China: Chinese Society of Comparative Law.
• Denmark: Danske Komité for Komparativ Ret.
• France: Société de Législation Comparée, 1869; Institut de Droit Comparé de Paris, 1931, based at the University of Paris Panthéon Assas (Paris II); Institut de Droit Comparé Edouard Lambert, 1920; Centre Français de Droit Comparé, 1951. There are many more French research centres – see The IALL International Handbook of Legal Information Management (details below).
• Germany: Gesellschaft für Rechtsvergleichung, 1950, University of Freiburg; Max-Planck Institut für ausländisches und internationales Privatrecht, Hamburg, 1926; Max-Planck Institut für ausländisches öffentliches Recht und Völkerrecht, Heidelberg, Berlin, 1924.
• Greece: Hellenic Institute of International and Foreign Law, 1939.
• Hong Kong: Centre for Chinese and Comparative Law, 1993, City University of Hong Kong.
• India: National Committee of Comparative Law; Centre for Comparative Law, National Law University, Delhi, 2014.
• Ireland: Irish Society of Comparative Law, 2008.
• Italy: Associazione Italiana di Diritto Comparato, 1958; Associazione Diritto Pubblico Comparato ed Europeo, 2001
• Japan: Japan Society of Comparative Law, 2003; Institute of Comparative Law in Japan, 1948, Chuo University; Waseda University Institute of Comparative Law, 1958.
• Norway: Norwegian Association for Comparative Law, 2007, based at the University of Oslo.
• Mexico: Instituto de Investigaciones Juridicas (formerly Instituto de Derecho Comparado), 1940, Universidad Nacional Autonoma de Mexico (UNAM); Academia Mexicana de Derecho Internacional Privado y Comparado, 1968.
• Netherlands: Nederlandse Vereniging voor Rechtsvergelijking (Netherlands Comparative Law Association), 1968; E.M. Meijers Institute for Legal Research, 1997, Universiteit Leiden.
• New Zealand: New Zealand Association of Comparative Law, 1995.
• Portugal: Gabinete de Documentação e Direito Comparado, 1980.
• Russia: Institute of Legislation and Comparative Law under the Government of the Russian Federation, 1925.
• Serbia: Institut za Oporedno Pravo (Institute of Comparative Law), 1956.
• South Africa: Centre for Foreign and Comparative Law, University of South Africa, Pretoria, founded 1964.
• Spain: Instituto de Derecho Comparado, 1951, Universidad Complutense de Madrid; Instituto de Derecho Publico Comparado „Manuel García Pelayo”, 1997, Universidad Carlos III de Madrid; Institute of European and Comparative Private Law (formerly the Observatory of European and Comparative Private Law) , University of Girona.
• Switzerland: Institut Suisse de Droit Comparé, 1982. United Kingdom: British Institute of International and Comparative Law, formed in 1958 by the merger of the Society of Comparative Legislation (1895) and the Grotius Society (1915); there is a separate British Association of Comparative Law (formerly the United Kingdom National Committee of Comparative Law); Institute of European and Comparative Law, 1995, University of Oxford.
• United States: American Foreign Law Association, 1925; American Society of Comparative Law, founded 1951; Parker School of Foreign and Comparative Law, based at Columbia University, New York, 1931; Eason Weinmann Center of Comparative Law, Tulane Law School, founded 1981. There are many more US research centers – see IALL International Handbook below).

For a fuller list of comparative law organizations and research centers, see “Comparative Law: Academic Perspectives ”, Appendices B and C, in The IALL International Handbook of Legal Information Management, Danner, R. A., and Winterton, J., (eds.), Ashgate, 2011 (Yale open access version). See also the American Society of Comparative Law’s list of Corresponding Foreign Institutional Members.

5. Research Guides to Foreign and Comparative Law

• JuriGlobe,from the University of Ottawa, provides an overview of the legal systems of the world, with a country listing and a clickable world map that makes a good attempt to reflect the often complicated and diverse influences at work.
• Germain, C. Germain’s Transnational Law Research: A Guide for Attorneys. Published by Transnational (1991 – ) in one loose-leaf binder.
• Reynolds, T. and Flores, A.A. Foreign Law: Current Sources of Codes and Legislation in Jurisdictions of the World. This eight-volume loose-leaf work, published by W.S. Hein, provides detailed information about national legal systems and resources. It is also available online from Brill publishing, as Foreign Law Guide, on subscription, with links to relevant websites.

6. Published Collections Relating to Several Jurisdictions

6.1. Print

• International Encyclopaedia of Comparative Law. 1971- , now published by Brill. 17 volumes; volume 1: National Reports, and volume 2: The Legal Systems of the World: Their Comparison and Unification, provide useful introductions. Also available via subscription.
• International Encyclopedia of Laws. A series of multi-volume loose-leaf titles published by Wolters Kluwer. Each of the 25 titles can be bought separately. Also available via subscription.
• Modern Legal Systems Cyclopedia. General editor K.R. Redden. W.S. Hein, 1984- Multi-volume loose-leaf publication; also available on the HeinOnline database.
• Central and East European Legal Materials.Edited by Michael Newcity. Juris Publishing, 1990- . Loose-leaf in 13 volumes.

6.2. Web Resources

• Worldlii: World Legal Information Institute. A collection of freely available full-text databases of primary (and some secondary) legal sources for numerous countries; also provides links to foreign law websites.
• Guide to Law Online, the Library of Congress’s annotated guide to sources of information on government and law for the nations of the world.

7. Specific Legal Subjects

Online resources of foreign law on specific subjects are thoroughly covered in Jennifer Allison’s article: Foreign law: subject law collections on the web, on this website.

There are several printed sources that provide the text of national legislation of a range of countries, by subject. For a very useful list, see the Library of Congress’s Global Legal Information Catalogue, based on its own holdings and linking to LoC catalogue entries. One can browse by jurisdiction, subject or title, or search by keyword, jurisdiction, subject, and/or author.

Constitutional Law

• Blaustein, A. P., Flanz, G. H., Grote, R. and Wolfrum, R., Constitutions of the countries of the world: a series of updated texts, constitutional chronologies and annotated bibliographies. OUP USA, 1971- . Multi-volume loose-leaf; also available online, by subscription.
• World Constitutions Illustrated: a module of the subscription-based HeinOnline service, offering current and historical constitutions, bibliographies and links to commentary.
• Oxford Constitutions of the World: another subscription-based online service, providing current constitutions, bibliographies and commentary.

Family Law

• Bergmann, A., Ferid, M., and Henrich, D., Internationales Ehe- und Kindschaftsrecht (International marriage and child law), published by Verlag für Standesamtswesen. Arranged alphabetically by countries of the world, with both commentary and texts of the relevant legislation, usually in parallel vernacular and German. Multi-volume loose-leaf; also online, by subscription.
• Ferid, M., Firsching, K. and Hausmann, R., Internationales Erbrecht (International inheritance law), published by Beck. Arranged alphabetically by country, with commentary and legislative texts. Multi-volume loose-leaf.
• Bring, M. (ed.), International Survey of Family Law, published by Intersentia. Annual review of developments in family law around the world, compiled by the International Society of Family Law.

Labour Law

• The International Labour Organization maintains Normlex, a free database of labour and social security laws and standards.
• Blanpain, R., (ed.), International encyclopaedia for labour law and industrial relations, published by Kluwer. Looseleaf. Now part of the International encyclopedia of laws.

Intellectual Property

• The World Intellectual Property Organization (WIPO) used to publish national copyright laws as supplements to its journals; this information has now been transferred to the WIPO-Lex open access platform (formerly Collection of Laws for Electronic Access (CLEA)).
• World Intellectual Property Rights and Remedies, edited by D. Campbell. Thomson Reuters. In six loose-leaf binders.
• World Patent Law and Practice, edited by J.W. Baxter. Matthew Bender. In 3 loose-leaf binders containing commentary, and 16 containing statutes, regulations and treaties.

Tax and Commercial Laws

• RIA Worldwide Tax Law database contains tax and commercial laws of over 90 countries, in English. Originally a loose-leaf publication, it is now a subscription database provided by Thomson Reuters.
• The International Bureau of Fiscal Documentation produces extensive guides to tax systems of the world, printed as loose-leaf sets but now also available online (by subscription), in the form of the IBFD Tax Research Platform.