Brian Z. Tamanaha

Brian Z. Tamanaha (born 1957) is an American legal scholar and the John S. Lehmann University Professor at Washington University School of Law in St. Louis, Missouri. He is primarily known for his work on legal pluralism, rule of law, legal realism, and a realistic theory of law grounded in philosophical pragmatism.^{[1][2][3][4][5]}

Tamanaha received his Bachelor of Science from the University of Oregon in 1980. He earned his Juris Doctor magna cum laude from Boston University School of Law in 1983. After practicing law for several years, he obtained his Doctorate of Juridical Science (S.J.D.) from Harvard Law School in 1992, working under Roberto M. Unger.^[6]

Following law school, Tamanaha clerked for the Honorable Walter E. Hoffman at the United States District Court for the Eastern District of Virginia from August 1983 to September 1984. He then served as an Assistant Federal Public Defender for the District of Hawaii from September 1984 to March 1986. In this position, he was primary defense counsel in United States v. Rewald, involving a Ponzi scheme that defendant Ron Rewald claimed was set up by the Central Intelligence Agency. Significant evidence was introduced during trial showing that the CIA worked with Rewald, although agency officials testified that they were unaware that Rewald's investment firm was a Ponzi scheme. During trial, Judge Harold Fong filed criminal contempt charges against Tamanaha on the grounds that his cross examination of CIA witnesses revealed unapproved classified information, although Fong denied Tamanaha's request to be released from the case, and he continued serving as Rewald's defense counsel. Following the completion of Rewald's trial, Federal District Judge Marilyn Hall Patel dismissed the contempt charges against Tamanaha.^[7][8]

Tamanaha was admitted to the Massachusetts Bar in 1984, the Hawaii Bar in 1986, and the bar of the Federated States of Micronesia in 1987.^[6]

From November 1986 to August 1988, Tamanaha served as Assistant Attorney General for Yap State in the Federated States of Micronesia,^[9][10] which had recently gained independence from the former Trust Territories of the Pacific Islands. This experience proved formative for his later academic work on law and development and legal pluralism. He observed firsthand how American law operated in a radically different cultural context, where traditional customary systems coexisted with the formal state legal system.^[11]

In 1990, he returned to Micronesia to serve as Legal Counsel for the Micronesian Constitutional Convention.^[12] In addition to advising on several constitutional provisions, Tamanaha successfully represented the Convention before the Supreme Court of Micronesia against an effort to limit the scope of the Convention.^[13]

His work in Micronesia provided the empirical foundation for his doctoral thesis on transplanted law and his later theoretical work on legal pluralism.^[6][14]

After teaching American Law to masters students in the Harvard Law School graduate program, Tamanaha began his academic career as Universitair Docent (Assistant Professor) at the University of Amsterdam from January 1991 to June 1995. He also served as Research Associate and Lecturer at the Van Vollenhoven Institute for Law and Administration in Non-Western Countries at Leiden University from March 1993 to June 1995.^[15][16]

In 1995, he joined St. John's University School of Law, where he served as Assistant Professor (1995-1997), and Associate Professor (1997-1999). While still an untenured professor, he served as Interim Dean from January 1998 to June 1999.^[3] He was appointed Professor in 1999, and Benjamin N. Cardozo Professor in 2003.^[15] Drawing on his experiences as Interim Dean and observations about rising debt and limited job prospects for recent graduates, Tamanaha wrote Failing Law Schools (Chicago 2012),^[17] a critical investigation of legal education. Although the book prompted a backlash from some legal educators, Tamanaha was voted "1# Most Influential Legal Educator" (2013) in a poll of 300 legal academics by National Jurist magazine.^[18]

In 2010, Tamanaha joined Washington University School of Law as Professor of Law. He was appointed William Gardiner Hammond Professor of Law in September 2011 and became the John S. Lehmann University Professor in July 2017.^[6]

• Distinguished Visiting Professor of Legal Theory, University of Amsterdam (Summers 2014-)
• Fernand Braudel Senior Fellowship, European University Institute, Florence (April-June 2018)
• Visiting Professor, Kobe University, Japan (December 2019-January 2020)
• Visiting Professor, Queen Mary University of London (Summer Fellowship, 2015-2017)
• Visiting Professor of Law, Columbia Law School (Spring 2009)
• Member, Institute for Advanced Study, Princeton (September 2007-August 2008)

Tamanaha’s book On the Rule of Law: History, Politics, Theory (2004) is a widely cited theoretical overview of the rule of law that has been translated into ten languages. In this book and a dozen articles on the topic, he conveys, among other aspects, the historical origins, institutional requirements, and strengths and limitations of the rule of law, and he examines the operation of the rule of law in a number of contexts, including international law, legal pluralism, and the Trump Administration.^{[19][20][21][22]}

Tamanaha has developed an influential non-essentialist approach to legal pluralism, challenging dominant conceptions in legal anthropology, sociology, and jurisprudence. His work argues that legal pluralism should not be understood as multiple manifestations of a single phenomenon called "law," but rather as the coexistence of different kinds and manifestations of law in the same social field. This conventionalist approach avoids the definitional problems that plague essentialist theories of legal pluralism, and allows scholars to account for the operation of customary law, religious law, international law, and state law in given contexts.^[23]

In his analysis "A Vision of Social-Legal Change: Rescuing Ehrlich from 'Living Law'" (2011), Tamanaha critiques the conceptual problems inherent in Eugen Ehrlich's concept of "living law," arguing that attempts to locate law in social order cannot distinguish it from other functional equivalents such as customs, morality, and social relations.^[24] He proposes that Ehrlich's more enduring contribution lies in his dynamic vision of law as continuously evolving within society rather than in the problematic concept of living law itself.

In Beyond the Formalist-Realist Divide (2010), Tamanaha set forth a revisionist account of legal realism that, among other things, challenges the standard narrative of the clash between the formalists and realists. Tamanaha argued that the "formalist age" was largely a fiction created by critics, and that significant aspects of legal realism were already articulated by historical jurisprudence and sociological jurisprudence.  Legal historian Stuart Banner commented, "As David Rabban and Brian Tamanaha have shown, even the most supposedly formalist judges and scholars of the era do not look particularly formalist when their work is examined closely."^[25] Tamanaha also argued that political science studies produce a distorted view of judging and fail to capture important ways in which judges follow the law when rendering their decisions.^{[26][27][28][29]}

Tamanaha has criticized contemporary analytical jurisprudence for its heavy reliance on intuitions and conceptual analysis to the exclusion of historical and sociological insights about law. His critique of universalistic claims in legal philosophy reveals multiple conceptual and empirical problems that arise when theorists attempt to identify essential truths about law that apply across all times and places.^[30] Drawing on philosophical pragmatism, Tamanaha has articulated a holistic vision of law within society evolving over time in connection with surrounding social, cultural, economic, technological, and political changes. ^[31] His work brings renewed attention to historical jurisprudence and sociological jurisprudence, which have been largely ignored by contemporary legal philosophers. Using this perspective, Tamanaha focuses on a broad range of legal phenomena, including legal pluralism, law and development, natural law, and the rule of law.^[31][32]

• Truth About Natural Law: History, Theory, Consequences (Oxford University Press, 2026)
• Sociological Approaches to Theories of Law (Cambridge University Press, 2022)
• Legal Pluralism Explained: History, Theory, Consequences (Oxford University Press, 2021)
• A Realistic Theory of Law (Cambridge University Press, 2017)
• Failing Law Schools (University of Chicago Press, 2012)
• Beyond the Formalist-Realist Divide: The Role of Politics in Judging (Princeton University Press, 2010)
• Law as a Means to an End: Threat to the Rule of Law (Cambridge University Press, 2006)
• Perils of Pervasive Legal Instrumentalism (Wolf Legal Publishers, 2006)
• On the Rule of Law: History, Politics, Theory (Cambridge University Press, 2004)
• A General Jurisprudence of Law and Society (Oxford University Press, 2001)
• Realistic Socio-Legal Theory: Pragmatism and a Social Theory of Law (Oxford University Press, 1997)
• Understanding Law in Micronesia: An Interpretive Approach to Transplanted Law (E.J. Brill, 1993)

• "Natural Law Errors and Wrongs" (2026)
• "Vertical and Horizontal Dimensions of the Rule of Law" (2024)
• "Pragmatic Reconstruction in Jurisprudence: Features of a Realistic Theory" (2021)
• "The Third Pillar of Jurisprudence: Social Legal Theory" (2015)
• "The Primacy of Society and the Failures of Law and Development" (2011)
• "Understanding Legal Pluralism: Past to Present, Local to Global" (2008)

• A Realistic Theory of Law won the 2019 IVR Book Prize from the International Association for Philosophy of Law and Social Philosophy for the best book in legal philosophy, and received an Honorable Mention Award from the Association of American Publishers in 2018.^[33]
• A General Jurisprudence of Law and Society earned both the 2002 Herbert Jacob Book Prize from the Law and Society Association and the inaugural 2006 Dennis Leslie Mahoney Prize from the Julius Stone Institute for outstanding contemporary work in sociological jurisprudence.^[34]
• Law as a Means to an End received an Honorable Mention Award from the Association of American Publishers for Best Professional/Scholarly Book in Law in 2006
• Realistic Socio-Legal Theory received a Special Recognition Award from the Law and Society Association in 1998.

• Selected as Professor of the Year at St. John's University School of Law (2001)^[9]
• Selected by students as the David M. Becker Professor of the Year at Washington University School of Law (2013)^[9]
• Voted the most influential legal educator in the United States by National Jurist magazine (a poll of over 300 law deans and professors, 2013)^[18]

Tamanaha has delivered the Dewey Lecture in the Philosophy of Law,^[18] Kobe Memorial Lecture,^[35] Julius Stone Address,^[36] Montesquieu Lecture,^[37] Cotterrell Lecture in Sociological Jurisprudence,^[38] George Wythe Lecture,^[39][40] Seegers Lecture, Baker & Hostetler Lecture,^[41] and Clason Lecture.

• Legal pluralism
• Legal realism
• Sociology of law
• Law and development
• Rule of law

• Faculty Profile at Washington University School of Law