Researching Comparative Constitutional Law

By Julienne E. Grant

Julienne E. Grant currently serves as Instructor & Reference Librarian at the Louis L. Biro Law Library at the University of Illinois Chicago School of Law. She previously spent almost eighteen years as the Foreign & International Research Specialist at the Loyola University Chicago School of Law. Ms. Grant has contributed to published guides on Mexican and Cuban law, and in 2019, she co-authored a chapter (with Teresa M. Miguel-Stearns) in Latin American Collection Concepts: Essays on Libraries, Collaborations and New Approaches (McFarland, 2019). She is a member of the FCIL-SIS of the American Association of Law Libraries and has served as Chair of its Latin American Law Interest Group. Ms. Grant earned B.A. magna cum laude in Spanish from Middlebury College, an M.A. in Ibero-American Studies from the University of Wisconsin-Madison, an M.A.L.S. from Rosary College (now Dominican University), and a J.D. cum laude from DePaul University. Ms. Grant also possesses a Certificate in Editing from the Graham School at the University of Chicago, and she is a freelance editor, writer, and translator.

Published September/October 2024

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1. What Is a Constitution?

Professor Aalt Willem Heringa of Maastricht University posits that the word “constitution” has both narrow and broad meanings in a socio-political context. Its narrow definition, according to him, is “a central written document that sets out the basic rules that apply to the government of socio-political entities, in particular states.”[1] In a broader sense, however, he asserts that “a constitution comprises the entire body of fundamental rules that govern that socio-political entity: be they contained in a central document or many documents, be they written down or be they customary rules. Substantively, therefore, a constitution is a body of law that: attributes power to public authorities; regulates the fundamental relations between public authorities; and regulates the fundamental relations between the public authorities and the individual.”[2] Thus, with the broader definition, a country or other polity may have a constitution without the existence of a central written document (such as in the case of the United Kingdom).

This guide will address the research techniques and resources for comparative constitutional law in the broadest sense of Professor Heringa’s definition of a constitution.

2. What Is Comparative Constitutional Law?

Contemporary scholars have struggled to define comparative constitutional law and its related terms, such as comparative constitutionalism. In his book Comparative Matters: The Renaissance of Comparative Constitutional Law (Oxford UP, 2014), Professor Ran Hirschl of the University of Toronto writes, “Since its birth, comparative constitutionalism has struggled with questions of identity. There is considerable confusion about its aims and purposes, and even about its subject—is it about constitutional systems, constitutional jurisprudence, constitutional courts, or constitutional government and politics? It also remains unclear whether comparative constitutional law is or ought to be treated as a subfield of comparative law, a subfield of constitutional law, or an altogether independent area of inquiry.”[3] More recently, however, Professor Madhav Khosla of Columbia University suggests that comparative constitutional law has “unquestionably emerged as a field of study in its own right,” but “much remains to be settled.”[4]

The modern vitalization of constitutional law in a comparative context has occurred in legal and judicial practice, as well as in academia. Professor Monica Claes (also of Maastricht University) attributes this dramatic growth in interest to several factors: an increase in constitutional activity across the world; the growing importance of constitutions and constitutional law in public life (including constitutional adjudication); an expanding interest in national identity; and the constitutionalizing trend in European and international governance.[5] According to her colleague Professor Heringa, the benefits of the practice of comparing constitutions are as follows: 1) the process aids in appreciating and understanding a researcher’s own constitutional system; 2) it provides useful material for constitution building and constitutional engineering; and 3) it establishes a basis for the creation and development of international organizations and their institutions (such as the EU and the Court of Justice of the European Union [CJEU]).[6]

For purposes of this guide, comparative constitutional law is considered an individual field that generally involves the study, analysis, and comparison of constitutions.

3. Research Overview

Comparative constitutional law intersects with other fields and disciplines, such as political science, history, human rights, philosophy, and anthropology; accordingly, researchers should not limit their investigations to traditional legal research sources like law journals and legal treatises. Professor Hirschl argues that “any attempt to portray the constitutional domain as predominately legal, rather than imbued in the social or political arena, is destined to yield thin, ahistorical, and overly doctrinal or formalistic accounts of the origins, nature, and consequences of constitutional law.”[7]

Similarly, researchers should recognize the semantic variations in the name of the field itself. For instance, comparative constitutional law is often equated or associated with comparative constitutional studies, comparative constitutionalism (as noted above), comparative constitutional change, comparative constitutional review, and comparative judicial politics. Researchers also need to be aware that general works on comparative law may include scholarship on the more specialized field of comparative constitutional law.

This guide proceeds with the assumption that there are multiple areas of research activity within the field. There are, for example, secondary works about comparative constitutional law, its research agendas, and its investigative methodologies. Other secondary sources present country-by-country descriptions of national constitutional histories and contents. Statistical studies have been designed that compare constitutional texts, themes, and structures—the results of which have been published in scholarly books and journal articles. Another investigative area focuses on judicial or, more specifically, constitutional review—that is, the process utilized to test and decide the constitutionality of legal acts. The scope of this area includes examining the decisions of constitutional courts and their judicial equivalents.

As such, the goal of this guide is to provide a roadmap for the numerous types of research conducted within the realm of comparative constitutional law. The guide first presents introductory materials about the field itself, as well as electronic platforms that can assist with all facets of researching comparative constitutionalism. The general category of secondary sources is addressed next, which identifies the field’s most important encyclopedic works; presents techniques for locating helpful books; lists relevant monographic series; identifies the field’s principal journals; and recommends sources for finding pertinent articles, theses, and dissertations. The guide then turns into a list of helpful websites and the constitutional scholar’s primary tools for conducting comparative work—constitutional texts and court decisions. News sources and blogs are next, followed by sources for historical constitutional research. The guide concludes with a compiled list of international and regional organizations that focus on constitutional law.

Within the guide’s content, emphasis is placed on English-language resources, although many of the techniques described below will lead to information in other languages, including constitutions in the vernacular. Greater focus is also placed on national constitutions rather than those at the subnational level, such as U.S. state constitutions. An *asterisk* in the text indicates a subscription database.

4. Introductory Materials

The following publications include in-depth introductions to the field of comparative constitutional law, including its history, research goals, and investigative methodologies.

  • Biagi, Francesco, Justin Orlando Frosini, and Jason Mazzone, eds. Comparative Constitutional History. Leiden: Brill, 2020–.
  • Contiades, Xenophon I., and Alkmene Fotiadou, eds. Routledge Handbook of Comparative Constitutional Change. Abingdon, UK: Routledge, 2021.
  • Frankenberg, Günter. Comparative Constitutional Studies: Between Magic and Deceit. Elgar Monographs in Constitutional and Administrative Law. Cheltenham, UK: Edward Elgar, 2018.
  • Heringa, Aalt Willem. Constitutions Compared: An Introduction to Comparative Constitutional Law. 7th ed. Den Haag: Eleven International Publishing, 2023.
  • Jackson, Vicki C., and Madhav Khosla, eds. Redefining Comparative Constitutional Law: Essays for Mark Tushnet. Oxford, UK: Oxford University Press, 2024 (forthcoming). See SSRN for various chapter drafts.
  • Jackson, Vicki C., and Mark Tushnet. Comparative Constitutional Law. 3rd ed. University Casebook Series. St. Paul, MN: Foundation Press, 2014.
  • Jackson, Vicki C., and Mila Versteeg, eds. Comparative Constitutional Law. 4 vols. Abingdon, UK: Routledge, 2021.
  • Jacobsohn, Gary, and Miguel Schor, eds. Comparative Constitutional Theory. Research Handbooks in Comparative Constitutional Law. Cheltenham, UK: Edward Elgar, 2019.
  • Jakab, András, Arthur Dyevre, and Giulio Itzcovish, eds. Comparative Constitutional Reasoning. Cambridge, UK: Cambridge University Press, 2017.
  • Landau, David, and Hanna Lerner, eds. Comparative Constitutional Making. Research Handbooks in Comparative Constitutional Law. Cheltenham, UK: Edward Elgar, 2019.
  • Law, David S., ed. Constitutionalism in Context. Cambridge, UK: Cambridge University Press, 2022.
  • Masterman, Roger, and Robert Schütze, eds. The Cambridge Companion to Comparative Constitutional Law. Cambridge, UK: Cambridge University Press, 2019.
  • Tushnet, Mark, and Dmitry Kochenov, eds. Research Handbook on the Politics of Constitutional Law. Research Handbooks on Law and Politics. Cheltenham, UK: Edward Elgar, 2023.

5. Electronic Research Guides

The online guides listed below serve as general pathfinders for comparative constitutional law research and serve as good starting points.

6. Secondary Sources

The study, analysis, and comparison of constitutions has yielded a large body of secondary literature that includes encyclopedias, books, monographic series, journal articles, and graduate theses and dissertations. These types of resources are addressed below.

6.1. Encyclopedias

The following list includes English-language encyclopedias in print and electronic format that are useful for all areas of comparative constitutional law research.

  • Alen, André, and David Haljan, eds. International Encyclopaedia of Laws: Constitutional Law.* Eleven vols. International Encyclopaedia of Laws. Alphen aan den Rijn, The Netherlands: Wolters Kluwer, 1996–. Available on the Kluwer Law Online platform, as well as in loose-leaf format, this set offers a nation-by-nation survey of constitutional law. Entries include information on the sources of constitutional law, the national form of government, and citizenship requirements. The collection also provides English-language translations of constitutional texts, as well as some coverage of subnational constitutions.
  • Cremades, Javier, and Cristina Hermida, eds. Encyclopedia of Contemporary Constitutionalism.* Cham, Switzerland: Springer, 2020. This online encyclopedia covers developments of a wide variety of constitutional law topics and offers in-depth comparative analyses at the national, regional, and international levels.
  • Katz, Stanley N., ed. Oxford International Encyclopedia of Legal History.* Six vols. Oxford, UK: Oxford University Press, 2009. This set contains entries on individual countries with information on their constitutional histories. Available in print, as well as online with a subscription.
  • Max Planck Encyclopedia of Comparative Constitutional Law* was launched in early 2017 and is available via Oxford University Press. The database’s topical coverage includes constitutional formation; civil and human rights; government structures; and key constitutional law cases from around the globe. The encyclopedia’s general editors are Rainer Grote, Frauke Lachenmann, and Rüdiger Wolfrum.
  • Max Planck Encyclopedia of Public International Law* is also available through Oxford University Press, appearing for the first time online in 2008. Although the source focuses on public international law, there are over one hundred entries relevant to the field of comparative constitutional law. The general editor of the work is Anne Peters.
  • Robbers, Gerhard, ed. Encyclopedia of World Constitutions. Three vols. New York: Facts on File, 2007. Although somewhat outdated, this set is still useful for historical background information.
  • Smits, Jan M. et al., eds. Elgar Encyclopedia of Comparative Law. 3rd ed. Cheltenham, UK: Edward Elgar, 2023. Along with entries on individual countries, this recently enlarged encyclopedia includes sections on more general legal topics, including constitutional law. Available in print and online.
  • Zweigert, Konrad, and Ulrich Drobnig, eds. International Encyclopedia of Comparative Law.* Forty-four vols. Leiden: Brill Nijhoff, 1981–. This extensive work includes national reports that incorporate discussions of each nation’s constitutional system. Available online with a subscription and in print.

6.2. Books & Monographic Series

Library of Congress Subject Headings (LCSHs) are assigned to books held in U.S. libraries and beyond and help identify subject-specific monographs and other materials. There is no single LCSH for the field of comparative constitutional law; items on this subject are generally tagged with two LCSHs—”Constitutional Law” and “Comparative Law.” Subtopics of comparative constitutional law, such as constitutional amendments, civil rights, and habeas corpus are assigned single headings and those may be combined with a jurisdiction—e.g., “Constitutional Amendments—Brazil.” The Library of Congress provides an online searchable database of LCSHs that is relatively easy to use.

Noteworthy are several monographic series that focus on comparative constitutional law, such as Elgar Monographs in Constitutional and Administrative Law, edited by Professors Rosalind Dixon, Susan Rose-Ackerman, and Mark Tushnet. Elgar also publishes the Research Handbooks in Comparative Constitutional Law series, edited by Professor Tom Ginsburg of the University of Chicago Law School. Professor Ginsburg also serves as editor of the Cambridge series Comparative Constitutional Law and Policy, along with Professors Zachary Elkins and Ran Hirschl. Routledge publishes the series Comparative Constitutional Change, edited by Professors Richard Albert, Xenophon Contiades, Thomas Fleiner, and Alkmene Fotiadou.

For monographs on the constitutional law of individual countries, the LCSH “Constitutional Law” may be combined with individual countries—e.g., “Constitutional Law—Spain.” Wolters Kluwer publishes a series on comparative law (see under the “International” pull-down menu) that includes separate books on the constitutional law of various countries, such as Argentina, China, and Hong Kong. The content of these books is derived from the aforementioned International Encyclopaedia of Laws. Hart Publishing offers the series Constitutional Systems of the World with separate monographs on Brazil, Myanmar, and Poland, among others. The general editors of the series are Professors Peter Leyland, Andrew Harding, Benjamin L. Berger, Rosalind Dixon, and Heinz Klug.

6.3. Serials & Periodical Indexes

Listed below are English-language serials that focus on constitutional law from a global or regional perspective. Note that academic journals that center on the constitutional law of a single jurisdiction may also be useful for comparative constitutional law research. Likewise, periodicals that concentrate on comparative law generally include articles on constitutional law topics. Each title below is followed by a parenthetical with the publisher’s name, as well as an indication if the publication is open access.

The following online periodical databases and indexes will also help identify and locate relevant articles. Searches in Google Scholar and SSRN may also be useful in this respect.

  • HeinOnline Law Journal Library* contains scanned images of U.S. and some foreign law reviews, generally back to their inception. An index of journal titles is available by subject (see “Comparative Law” and “Constitutional Law”) and country of publication.
  • Index to Foreign Legal Periodicals* (IFLP) is available electronically through HeinOnline and indexes foreign (including some non-English-language) law journals. Relevant subjects include “Constitutions,” “Constitutional Amendments,” “Constitutional History,” “Constitutional Law,” and “Constitutional Courts.” Journal titles are listed by region and country. IFLP is produced by the American Association of Law Libraries and the University of California, Berkeley School of Law.
  • Kluwer Law International Journal Library* is available through HeinOnline. The database includes twenty-three journals from Wolters Kluwer that analyze topics in international law, including constitutional law.
  • Worldwide Political Science Abstracts* is a ProQuest database that offers citations, abstracts, and indexing of political science literature, and related fields, such as comparative constitutional law. For other databases that include political science literature, see JSTOR* and Project Muse.*

6.4. Theses & Dissertations

Often overlooked by researchers, theses and dissertations contain exhaustive research and extensive bibliographies and may serve as useful sources of information on comparative constitutional law subjects. Along with the web platforms listed below, many universities post digital copies of their own students’ theses and dissertations.

  • DART-Europe E-theses Portal is an open-access portal. It is a partnership of various European research libraries and library consortia. It provides access to theses from over 600 European universities. The database is multilingual.
  • Open Access Theses and Dissertations is an online collection of open-access theses and dissertations from around the globe. Over 1,000 education and research institutions are represented.
  • ProQuest Dissertations & Theses Global* “continues to grow its repository of 5 million graduate works each year, thanks to the continued contribution from the world’s universities.”

7. Useful Websites

Listed below are several websites that contain potentially valuable information for scholars engaged in comparative constitutional law research.

  • Comparative Constitutions Project (CCP) was launched in 2005 at the University of Illinois Urbana-Champaign. In addition to the Constitute database highlighted below, the CCP website offers a variety of information on the world’s constitutions, including comparative data and rankings.
  • ConstitutionNet is a platform and project of IDEA (International Institute for Democracy and Electoral Assistance), which is headquartered in Stockholm. Included on the site are in-depth country reports, which include constitutional history, government information, and current developments. ConstitutionNet also provides full-text access to IDEA’s publications that cover topics such as constitution building, constitutional rights, and the judiciary.
  • Global Constitutionalism Seminar Publications are posted on the web page of the Gruber Program for Global Justice and Women’s Rights at Yale Law School. The program sponsors an annual multi-day seminar on selected facets of global constitutionalism, attended by Supreme Court and constitutional court justices from around the world, as well as academics. Prior to each seminar, a special coursebook is compiled and posted on the Gruber Program’s page.
  • WORLD Policy and Analysis Center: Constitutions is an outgrowth of the UCLA Fielding School of Public Health. The center has examined the civil, political, social, economic, and equal rights in the constitutions of all 193 UN member states and has analyzed over fifty specific constitutional rights across a range of areas. Interactive maps on the website provide a sample of WORLD findings regarding the existence and quality of constitutional protections.

8. National Constitutions & Associated Legislation

For online guides to researching national constitutions, try Googling the term “LibGuide” with the name of the jurisdiction and “constitution” or “constitutional law.” The Bodleian Libraries at the University of Oxford have compiled legal research guides for various countries that include separate sections on their constitutions. Some examples of these helpful guides are listed below, along with other useful research platforms for selected domestic constitutions. GlobaLex articles on specific countries may also help identify sources of information about those nations’ constitutions. For Latin America, see Dante Figueroa and Daniel Rocha de Farias’s GlobaLex contribution on “Current Constitutional Developments in Latin America,” most recently updated in 2021.

Also noteworthy is the interactive tutorial “How to Research Foreign Constitutions”* (Brian Huddleston, Loyola University College of Law, New Orleans), which is posted on the Web platform of the Center for Computer-Assisted Legal Instruction (CALI). This excellent lesson explains how to utilize various electronic resources, including Westlaw* and Lexis,* to research the constitutions of jurisdictions outside of the United States. A subscription to CALI is required for access.

An important research activity within the field of comparative constitutional law is the analysis of a selected spectrum of constitutional texts, themes, or designs. Several electronic resources provide access to the full texts of the world’s constitutions and associated laws, many in English-language translation. Below are listed the most useful of these resources. Note that national parliament and government websites often provide direct access to the most current version of a country’s constitution, with amendments directly incorporated into the constitutional text. The annual Guide to International Legal Research,* compiled by staff of the George Washington International Law Review, is available in print and online in LexisNexis. Use the volume’s “Subject Matter Index,” and then go under the “Constitutions” heading to identify sections in the guide that cover the constitutions of individual nations.

  • Constitute was developed by the authors of the CCP (listed above) at the University of Texas at Austin. This online compendium of constitutions in English-language translation features the ability to easily cross-compare constitutional passages by topic. A private login feature is offered for a fee, which provides access to historical and draft texts not available to the general public.
  • Foreign Law Guide* is a staple in the area of foreign legal research. Included are brief overviews of the legal systems of over 170 jurisdictions, as well as lists of each jurisdiction’s codes, court reports, and other significant legal literature. For information on constitutional law, check under the “Constitution & Politics” heading for each country listing.
  • Global-Regulation* enables searching across the laws of over one hundred jurisdictions. Some constitutional amendatory and implementing acts are included. Laws are machine translated into English, but links are provided to the official texts. The database is updated monthly.
  • Guide to Law Online: Nations is a set of annotated Web guides to locating and researching national law, organized alphabetically by country. Each entry includes a separate section on the constitution with links to the text and other relevant documents. The Law Library of Congress hosts the site, and library staff members maintain and update it.
  • Oxford Constitutions of the World* is Oxford University Press’s collection of national (and subnational) constitutions in English-language translation, complemented by secondary materials. The texts of amendatory acts are included, as well as laws and analyses related to constitutional courts. Personnel at the Max Planck Institute for Comparative Public Law and International Law edit the source.
  • World Constitutions Illustrated* is available on HeinOnline, providing access to historical and current texts of national constitutions in their original language. Most of the current constitutions are also available in English-language translation. Full texts of relevant monographs, journal articles, and other secondary materials are likewise included, many in English.

9. Constitutional Review

A constitution, be it written or unwritten, is generally recognized as the supreme law in a jurisdiction’s legal system. According to Professor Günter Frankenberg (Goethe University), “Superiority is ascertained, technically, by the systematic ranking of constitutional norms at the top of the legal hierarchy, above the ordinary laws, and by the methodological rule that laws have to be interpreted in conformity with the constitution.”[8] Constitutional review (sometimes used synonymously with “judicial review”) is the process by which a judicial authority checks legal acts for compliance with the constitution. A judicial authority can take different forms, but for the most part, it follows a U.S. model (a supreme court) or a European model (a constitutional court).[9]

In the U.S. model, constitutional review is included within the overall subject-matter jurisdiction of a country’s highest appellate court. In contrast, in the European model, a specialized constitutional court is charged with the task of determining the constitutionality of legal acts. This is, of course, a simplified description, as there are hybrid forms, and in some instances, the judicial authority for constitutional review is not a court per se. Researchers are referred to the Max Planck Encyclopedia of Comparative Constitutional Law* for detailed descriptions and examples of the various kinds of constitutional review. For a chart of constitutional review models with the corresponding countries that utilize them, see Nova Univerza (New University) Professor Arne Marjan Mavčič’s useful Concourts.net website.[10]

Below are recently published secondary sources on constitutional review in a comparative context, along with tips for identifying and locating the decisions of constitutional courts and their judicial equivalents.

9.1. Secondary Sources

The LCSH “Constitutional Courts” will identify books on the subject in online library catalogs. The “Constitutional Courts” heading can be combined with a region or single jurisdiction, such as “Constitutional Courts–Italy.” Another relevant LCSH is “Judicial Review,” which can likewise be combined with a specific region or country. The IFLP mentioned above includes the indexing terms “Judicial Review” and “Constitutional Courts,” which will pinpoint journal articles. The following is a sample list of recent secondary sources related to the topic of comparative constitutional review.

  • Dahlberg, M. “Openness of Constitutional Review: A Comparative Analysis of How Transparency Is Ensured in Ex Ante Constitutional Review.” In European Yearbook of Constitutional Law 2021. European Yearbook of Constitutional Law, vol 3, edited by J. de Poorter et al., 155–96. The Hague: T.M.C. Asser Press, 2022.
  • Fröhlich, Johanna, ed. Constitutional Reasoning in Latin America and the Caribbean. Oxford, UK: Hart Publishing, 2024 (forthcoming).
  • Ginsburg, Tom, and Mila Versteeg. “Models of Constitutional Review.” In The Oxford Handbook of Comparative Judicial Behaviour, edited by Lee Epstein et al. Oxford, UK: Oxford Academic, chapter online Feb. 22, 2024.
  • Grabenwarter, Christoph et al. “The Role of the Constitutional Courts in the European Judicial Network.” European Public Law 27, no. 1 (2021): 43–62.
  • Granat, Mirosław, ed. Constitutionality of Law Without a Constitutional Court: A View from Europe. Abingdon, UK: Routledge, 2024.
  • Kim, D., and P. Nolette. “The Institutional Foundations of the Uneven Global Spread of Constitutional Courts.” Perspectives on Politics 22, no. 1 (March 2024): 294–311.
  • Mavčič, Arne Marjan, ed. Constitutional Review Systems around the World. Lake Mary, FL: Vandeplas, 2018.
  • Pieters, Danny, ed. The Constitutional Courts of Small Jurisdictions. Abingdon, UK: Routledge, 2024.
  • Pócza, Kálmán, ed. Constitutional Review in Western Europe: Judicial-Legislative Relations in Comparative Perspective. London: Routledge, 2024.
  • Saunders, Cheryl. “Courts with Constitutional Jurisdiction.” In The Cambridge Companion to Comparative Constitutional Law, edited by Roger Masterman and Robert Schütz, 414–40. Cambridge, UK: Cambridge University Press, 2019.
  • Schoeller-Schletter, Anja, ed. Constitutional Review in the Middle East and North Africa. Baden-Baden: Nomos, 2021.
  • Sinani, Blerton. “Global Patterns of Constitutional Judicial Review Systems: Two Major Models of Constitutional Judicial Review in the World.” Tribuna Juridică 14, no. 1 (2024): 155–72.

9.2. National Court Decisions

A good resource for determining where national court decisions, including those of constitutional courts, are published is The Bluebook (see Table 2, Foreign Jurisdictions, which is now available online without a subscription). The Mavčič book listed above indicates whether a national body of constitutional review publishes its decisions in an official gazette or digest, legal journals, electronically, and/or in “other forms.” Most national courts and other judicial bodies post their decisions on their websites, although English-language translations of opinions tend to be scarce. The following resources also publish national court decisions periodically.

  • International Law Reports* (ILR) is published by Cambridge University Press and is “devoted to the regular and systematic reporting in English” of national and international court opinions. Four volumes are published annually, and the set has consolidated indexes. ILR is available in print and online.
  • International Legal Materials* (ILM) is published by the American Society of International Law six times annually. ILM reprints selected legislation, international agreements, and judicial decisions, and is available via several commercial online platforms, including Westlaw.*

The e-Bulletin on Constitutional Case-Law, compiled by the Council of Europe’s European Commission for Democracy through Law (the “Venice Commission”) reports on decisions of constitutional courts and their jurisdictional equivalents in Europe and beyond. The bulletin is released three times per year; free email subscriptions are available. The cases in the bulletin are added to the Venice Commission’s CODICES database. This useful platform contains the full texts and English-language summaries of thousands of decisions, including those from the Court of Justice of the European Union (CJEU) and the European Court of Human Rights (ECtHR), which involve constitutional questions. The Venice Commission site also includes a list of constitutional review institutions with their website addresses.

9.3. International & Regional Tribunal Decisions

Some international and regional tribunals hear appeals from national courts, including constitutional courts, and they have certain functions of constitutional review. According to Professor Mavčič, these tribunals include the CJEU, the ECtHR, the European Free Trade Association Court, the Inter-American Court of Human Rights, the Central American Court of Justice, and the African Court on Human and Peoples’ Rights.[11] All of these tribunals’ decisions are posted on their respective websites; the ECtHR’s caselaw database, HUDOC, allows narrowing by ECtHR opinions that reference a constitutional court in the text (see the “Court” heading under “More Filters”).

Professors Federico Fabbrini (Dublin City University) and Miguel Poiares Maduro (European University Institute) have coined the term “supranational constitutional courts” to describe those international tribunals that have a constitutional character and meet six requirements: jurisdiction extending beyond inter-state disputes; possession of a set of substantive powers of review analogous or equivalent to those of national constitutional courts; “subjectivization” of underlying treaties; development of a hermeneutic that is autonomous from international law; embracement of the core doctrines of constitutional law; and widespread social and institutional support.”[12] Professors Fabbrini and Maduro posit that the CJEU is the paradigmatic example of a supranational constitutional court and that the ECtHR is moving in that direction.

The actual relationship between European national courts and the CJEU is highly complex and unsettled. Leiden University Professor Darinka Piqani has noted the circumstances when domestic tribunals and the CJEU tend to cooperate: preliminary rulings on EU law, uncertainty about the constitutionality of national implementing measures, questions on the constitutionality of EU treaties, and controversies about the constitutional compatibility between national legislation and EU law.[13] It is worth pointing out that the EU attempted to create and implement a Constitution for Europe in the early 2000s, but the initiative failed when French and Dutch voters voted against its ratification in 2005.

10. Current Awareness: News Sources and Blogs

Newspaper and news websites, as well as blogs, can be excellent sources for information on constitutional developments around the world. Onlinenewspapers.com provides a comprehensive directory of the world’s newspapers with links to their websites.

The following is a list of selected news sources and blogs that cover constitutional law in a regional or global context. Note that a comprehensive collection of links for legal-related blogs is available on JUSTIA’s BlawgSearch; the lists there are organized by practice area, geographic focus, and by law school sponsorship.

  • European Law Blog (Topic: EU Constitutional Law) is authored by various academics and practitioners. The posts focus on developments in the EU in the context of constitutional law, including case opinions of the CJEU.
  • EUROPP blog, supported by the London School of Economics and Political Science’s European Institute, follows events in Europe. According to the site, its “central aim is to increase the public understanding of European politics and policy by providing accessible academic commentary and research.”
  • Global Legal Monitor is compiled by personnel at the Law Library of Congress (LLOC) in the United States. The source provides regular email updates on legal developments, including constitutional changes, around the world. The archives may be searched by country. See also the LLOC’s blog, In Custodia Legis, for occasional posts on constitution-related topics.
  • IACL-AIDC Blog is the official blog of the International Association of Constitutional Law. Coedited by Elisabeth Perham, Mariana Velasco-Rivera, and Pravar Petkar, blog posts respond to constitutional law developments, frame important debates, provide much-needed context, make useful links between different developments, and look ahead to what constitutional developments may take place in the future.” Along with posts, the platform includes author interviews and announcements about new books.
  • I·CONnect: Blog of the International Journal of Constitutional Law offers regular blog posts and a weekly “What’s New in Public Law.” The blog provides updates on new constitutional cases, amendments, constitution-making efforts, and a forum for analysis of major issues in the field of comparative constitutional law.

11. Digital Archives & Historical Materials

The following resources are useful for conducting historical comparative constitutional law research, as well as identifying more contemporary sources.

  • HathiTrust Digital Library* is a partnership of over one hundred research institutions and libraries. Many of the works contained in this multidisciplinary and multinational database are in the public domain, including several nineteenth-century works on comparative constitutionalism. Only partner institutions, however, are permitted to access some areas of the platform.
  • LLMC Digital* (Law Library Microfilm Consortium) is a repository for at-risk legal and government materials. In its vast database, LLMC Digital includes selected historical primary and secondary sources related to foreign constitutional matters. Examples of the aforementioned are a two-volume set of Pakistani constitutional documents (published in 1947), a 1907 publication on Canadian constitutional history, and an 1897 title on the “new constitutional laws for Cuba” (in English).

12. Institutes, Centers & Associations

Listed below are various initiatives and organizations that focus on comparative constitutional law or include that topic within their realm of activities. Note that many jurisdictions have associations or societies devoted to the study of national constitutional matters—e.g., the Australian Association of Constitutional Law.


[1] Aalt Willem Heringa, Constitutions Compared: An Introduction to Comparative Constitutional Law, 5th ed. (Cambridge, UK: Intersentia, 2019), 4.

[2] Id.

[3] Ran Hirschl, Comparative Matters: The Renaissance of Comparative Constitutional Law (Oxford, UK: Oxford University Press, 2014), 4.

[4] Madhav Khosla, “Is a Science of Comparative Constitutionalism Possible?,” Harvard Law Review 135, no. 8 (June 2022) (reviewing Adam Chilton and Mila Versteeg, How Constitutional Rights Matter [2020]).

[5] Monica Claes, “Constitutional Law,” in Elgar Encyclopedia of Comparative Law, 2nd ed., ed. Jan M. Smits (Cheltenham, UK: Edward Elgar, 2012), 224–25.

[6] Heringa, supra note 1, at 1.

[7] Hirschl, supra note 3, at 152.

[8] Günter Frankenberg, “Comparative Constitutional Law,” in The Cambridge Companion to Comparative Law, eds. Mauro Bussani and Ugo Mattei (Cambridge, UK: Cambridge University Press, 2012), 171.

[9] For detailed explanations of judicial review and the various constitutional review court models, see Rainer Grote, “Judicial Review,” and Virgilio Afonso da Silva, “Constitutional Courts/Supreme Courts, General,” in Max Planck Encyclopedia of Comparative Constitutional Law (Oxford, UK: Oxford University Press, 2018).

[10] See Arne Marjan Mavčič, Models of Constitutional/Judicial Review, The Legal Information System (last visited July 24, 2024). The chart is near the bottom of the page before the footnotes.

[11] Id.

[12] Federico Fabbrini and Miguel Poiares Maduro, “Supranational Constitutional Courts,” in Max Planck Encyclopedia of Comparative Constitutional Law (Oxford, UK: Oxford UP, 2018).

[13] Darinka Piqani, “Relation of Supreme Courts/National Courts to EU Courts,” in Max Planck Encyclopedia of Comparative Constitutional Law (Oxford, UK: Oxford UP, 2018).