A Plea for Private International Law (Conflict of Laws)

Michael S. Green*

Public international law primarily deals with the legal rights and duties of nations.  But there is another body of international law—private international law—that seeks to coordinate private legal rights and duties in cases that straddle national borders or involve citizens of different countries.

This law has a long history.[1]  But it really took off with the expansion of travel, communication, and trade in the nineteenth century.  And American courts played an outsized role in its development.  Because the constituent states of the United States were, in large part, understood as retaining the sovereignty of nations, American courts took private international law to be implicated in interstate cases too.  As a result, they were forced to develop and apply this body of law much more than the courts of other nations.  Indeed, in the nineteenth century the normal dependence of American cases on English precedents was often reversed: when a private international law issue came up, English courts looked to the Americans.[2]  This influence extended even to civil law jurisdictions, where Justice Joseph Story’s treatise on the topic, first published in 1834, was highly influential.[3]

By the early twentieth century, private international law was considered of sufficient importance to legal education in this country that a class on the topic was invariably offered.[4]  Indeed, it was not unusual for it to be a required course in the final year.[5]  This was not just because it was important for practitioners.  It also functioned as a course on jurisprudence, exploring the law’s foundations and structure.[6]  It is not surprising, therefore, that American philosophers of law as diverse as Wesley Newcomb Hohfeld, the American legal realists, and Ronald Dworkin started out working on it.[7]

Private international law can reveal law’s structure by forcing a court to dissociate—and assign to different jurisdictions’ authority—legal elements that tend to be conjoined (and so conflated) in a fully domestic case.[8]  And, by taking a panoptic perspective on multiple legal systems, it can bring into focus questions of law’s ultimate source.[9]  When a jurisdiction’s law extends to a fully local transaction, questions of its validity tend to stop with the highest domestic law—the jurisdiction’s constitution and the domestic legal practices keeping it in force.  But private international law may also ask whether a law can validly extend to an interjurisdictional transaction even when such domestic requirements are satisfied.[10]

Private international law can also inspire reflection on fundamental legal categories—such as tort, contract, property, status, and procedure.  This is because traditional choice-of-law methods (still used by a handful of states in this country) see a jurisdiction’s regulatory power as depending on the category within which the issue falls.  To be sure, more modern methods don’t care as much about categorization.  Their primary concern is usually whether the competing laws, when properly interpreted, extend to the interjurisdictional facts.[11]  But here too private international law has profound implications, for it can shed a new and disorienting light on questions of statutory interpretation.[12]

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*Michael S. Green (William & Mary Law School), with Lea Brilmayer (Yale Law School), John F. Coyle (University of North Carolina School of Law), William S. Dodge (George Washington University Law School), Scott Dodson (UC Law San Francisco), Peter Hay (Emory School of Law), Luke Meier (Baylor Law School), Jeffrey Pojanowski (Notre Dame Law School), Kermit Roosevelt III (University of Pennsylvania Carey Law School), Joseph William Singer (Harvard Law School), Symeon C. Symeonides (Willamette University College of Law), Carlos M. Vázquez (Georgetown University Law Center), Christopher A. Whytock (UC Irvine School of Law), and Patrick Woolley (University of Texas School of Law).

[1]See, e.g., Peter Hay, Patrick J. Borchers & Symeon C. Symeonides, Conflict of Laws 5–141 (5th ed. 2010); Hessel E. Yntema, The Historic Bases of Private International Law, 2 Am. J. Compar. L. 297 (1953); Friedrich K. Juenger, A Page of History, 35 Mercer L. Rev. 419 (1984).

[2]E.g., The Sussex Peerage Case (1844) 8 Eng. Rep. 1034, 1055 (HL).

[3]See, for example, the influence of Joseph Story, Commentaries on the Conflict of Laws (Boston, Hillard, Gray, & Co. 1834), on Friedrich Karl von Savigny, discussed in Roxana Banu, Nineteenth-Century Perspectives on Private International Law 27–43 (2018).

[4]See Joseph H. Beale, The Conflict of Laws, 1886–1936, 50 Harv. L. Rev. 887, 888 (1937) (stating that the course “is now probably offered in all those [law schools] of the first class”); David F. Cavers, Reviews, 46 Yale L.J. 1098, 1099 (1937) (reviewing Elliot E. Cheatham, Noel T. Dowling & Herbert F. Goodrich, Cases and Other Materials on Conflict of Laws (1936) and Charles Wendell Carahan, Cases and Materials on Conflict of Laws (1935)) (“[T]he Conflict of Laws is one of the major courses from the standpoints of hours allotted and of student attendance in the third year law curriculum in most law schools.”); Association of American Law Schools, Handbook of the Association of American Law Schools and Proceedings of the Twenty-First Annual Meeting 66 (1923) (stating that most graduates of a law school will have covered constitutional law and conflict of laws).

[5]We were able to find a smattering of old law school catalogs through a Google Book search for the period 1920–25.  Around half had conflicts as a required course.  See, e.g., La. St. Univ., Louisiana State University Catalogue, 1919–1920: Announcements, 1920–1921, at 126 (1920) (listing Conflict of Laws as a required course); Washington Univ. St. Louis, Bulletin of Washington University St. Louis: Sixty-Seventh Annual Catalogue 282–85 (1924) (same); Northwestern Univ., Northwestern University Bulletin: Annual Catalog 1922–1923, at 293 (1923) (same); The Cath. Univ. of Am., Courses of Study 1924–1925, at 35–39 (1924) (same); Univ. of Ill., University of Illinois Annual Register 1919–1920, at 206 (1920) (same); Vanderbilt Univ., Register of Vanderbilt University for 1923–1924: College of Arts and Science, School of Engineering; Announcement for 1924–1925, at 143–45 (1924) (same); Univ. of Miss., Announcements and Catalogue of the University of Mississippi: Sixty-Ninth Session Seventy-Third Year 1920–1921, at 108–09 (1921) (same); Yale Univ., Catalogue of Yale University: 1924–1925, at 265–68 (1924) (listing Conflict of Laws as an elective course); Univ. of Mo., Catalog: Seventy-Seventh Report of the Curators to the Governor of the State 1918–1919; Announcements 1919–1920, at 250 (1919) (same); Georgetown Univ., General Catalogue of the University: 1920–1921, at 98 (1921) (same); Univ. of Kan., General Information 64–65 (1921) (same); Univ. of S. Cal., Year Book for 1923–1924 with Announcements for 1924–1925, at 242 (1924) (same); Stanford Univ., Announcement of Courses 1920–21, at 118–121 (same); Univ. of Minn., The Bulletin of the University of Minnesota: The Law School Announcement for the Year 1923–1924, at 13 (1923) (same); Univ. of Pa., Catalogue of the University of Pennsylvania for the Session of 1921–22, at 179–80 (1921) (same); University of Cal., Announcement of Courses of Instruction in the Departments at Berkeley for the Academic Year, 1922–23, at 143–45 (1922) (same); N.Y. Univ., Catalogue: 1922–1923, at 218–19 (appearing to be required); Cornell Univ., Announcement of the Thirty-Fourth Summer Session 1925: July 6—August 14, at 46 (1925) (appearing to be an elective); The Ohio State Univ., College of Law 1922–1923, at 14 (1922) (same); Univ. of Mich., Catalogue of the University of Michigan 1922–1923, at 540–41 (1923) (same); Univ. of Idaho, Twenty-Ninth Annual Catalog of the University of Idaho with Announcements for 1921–1922, at 177–78 (1921) (same); Columbia Univ., Catalogue 1921–1922, at 225–26 (1922) (same).  At Harvard it appears that conflicts was elective but was de facto required.  See Sidney Post Simpson, The New Curriculum of the Harvard Law School, 51 Harv. L. Rev. 965, 974 n.20 (1938) (stating that a considerable majority of the third-year class chose five courses: Business Organizations III, Conflict of Laws, Constitutional Law, Property III, and Taxation).

[6]Felix Frankfurter, Joseph Henry Beale, 56 Harv. L. Rev. 701, 703 (1943) (stating that conflicts functioned as a “course in Jurisprudence”).

[7]See Wesley Newcomb Hohfeld, The Individual Liability of Stockholders and the Conflict of Laws, 9 Colum. L. Rev. 492, 493 (1909); Karl N. Llewellyn, Jurisprudence: Realism inTheory and Practice 491–92 (1962) (describing Hohfeld’s teaching in the conflict of laws); Walter Wheeler Cook, The Logical and Legal Bases of the Conflict of Laws, 33 Yale L.J. 457, 458 (1924); Hessel E. Yntema, The Hornbook Method and the Conflict of Laws, 37 Yale L.J. 468, 468 (1928); Ronald Dworkin, Comments on the Unity of Law Doctrine, in Ethics and Social Justice 200–01 (Howard E. Kiefer & Milton K. Munitz eds., 1968).

[8]See Cook, supra note 7, at 461.

[9]See Cook, supra note 7, at 459.

[10]For this reason, it can cast doubt on the view—standing behind modern Anglophone positivism—that all law ultimately depends upon a particular community’s law practices.  See Michael S. Green, Jurisdiction and the Moral Impact Theory of Law, 29 Legal Theory 29, 62 (2023).

[11]See Brainerd Currie, Selected Essays on the Conflict of Laws 183–84 (1963); Kermit Roosevelt III, Resolving Renvoi: The Bewitchment of Our Intelligence by Means of Language, 80 Notre Dame L. Rev. 1821, 1870–71 (2005).

[12]For example, a court facing a choice-of-law question can be required to determine whether a jurisdiction’s absence of law applies to the facts, for it may be forced to choose between a jurisdiction that has a cause of action and one that does not.