Introduction

Imagine the lost world of “lawfinding.” 1Open this footnote Close this footnote 1 It’s easy if you try. See Loper Bright Enterprises v. Raimondo, 144 S. Ct. 2244, 2285 (2024) (Gorsuch, J., concurring) (referring to “a very old idea, one that constrains judges to a lawfinding rather than lawmaking role”); Stephen E. Sachs, Finding Law, 107 Calif. L. Rev. 527, 529 (2019) (describing the view that unwritten law is made, not found, as the “modern approach” and tracing it to Erie Railroad Co. v. Tompkins, 304 U.S. 64 (1938)). …Open this footnote Close In that world, there was a general common law for federal judges to find. 2Open this footnote Close this footnote 2 See, e.g., Swift v. Tyson, 41 U.S. (16 Pet.) 1, 18-19 (1842) (finding general common law). …Open this footnote Close And in that world, each statute had a “single, best meaning” 3Open this footnote Close this footnote 3 Loper Bright, 144 S. Ct. at 2266 (majority op.). …Open this footnote Close for judges to unearth with the traditional tools of statutory interpretation.

Of course, we are not going back to that world. Too much has happened. Take Erie Railroad Co. v. Tompkins, a battle over corporate power that taught us there is no “federal general common law” out there to be found. 4Open this footnote Close this footnote 4 Erie, 304 U.S. at 78; see id. at 79 (rejecting the “assumption that there is ‘a transcendental body of law outside of any particular State’” (quoting Black & White Taxicab & Transfer Co. v. Brown & Yellow Taxicab & Transfer Co., 276 U.S. 518, 533 (1928) (Holmes, J., dissenting)). On the history of corporate litigants’ exploitation of diversity jurisdiction leading up to Erie, see Edward A. Purcell, Jr., Litigation and Inequality: Federal Diversity Jurisdiction in Industrial America 1870-1958, at 226-30 (1992). …Open this footnote Close And then there was the battle of the bubble: Chevron USA Inc. v. Natural Resources Defense Council. 5Open this footnote Close this footnote 5 467 U.S. 837, 865 (1984) (holding that federal courts should defer to permissible agency interpretations of ambiguous statutes that they administer). On the controversy about the Environmental Protection Agency’s bubble policy and Chevron, see Thomas W. Merrill, The Story of Chevron: The Making of an Accidental Landmark, 66 Admin L. Rev. 253 (2014). …Open this footnote Close Its lesson was that interpreting ambiguous statutes involves policymaking, which is for agencies to do when ambiguities appear in statutes they administer. 6Open this footnote Close this footnote 6 Chevron, 467 U.S. at 865 (“Courts must, in some cases, reconcile competing political interests, but not on the basis of the judges’ personal policy preferences. In contrast, an agency to which Congress has delegated policymaking responsibilities may, within the limits of that delegation, properly rely upon the incumbent administration’s views of wise policy to inform its judgments.”). …Open this footnote Close

And yet, there are signs of that lost world all round us. Chevron is gone now. The problem with Chevron deference, which the Roberts Court overruled in Loper Bright Enterprises v. Raimondo, was that it was a judge-made “fiction” that confused construing the law with lawmaking. 7Open this footnote Close this footnote 7 Loper Bright, 144 S. Ct. at 2268-69, 2273 (overruling Chevron, 467 U.S. 837). …Open this footnote Close In other words, Chevron failed at “lawfinding,” which, as Justice Gorsuch’s concurring opinion in Loper Bright put it, was the “traditional” task of judges. 8Open this footnote Close this footnote 8 See id. at 2277 (Gorsuch, J., concurring). …Open this footnote Close Somewhere out there is Swift v. Tyson, 9Open this footnote Close this footnote 9 41 U.S. (16 Pet.) 1 (1842). …Open this footnote Close still lumbering along, long after Erie’s impact. 10Open this footnote Close this footnote 10 See Abbe R. Gluck, Overruling Chevron Without a Coherent Theory of Statutory Interpretation and the Court-Congress Relationship, 62 Harv. J. Legis. 20, 26 (2024) (“Justice Gorsuch writes [in Loper Bright] as if Erie was never decided.”). …Open this footnote Close

Administrative law is not the only field in which something Swiftian can be found in the jurisprudence of one (or more) of the Roberts Court justices. Federal Indian law, the subject of this symposium, is another. Federal Indian law is a field full of fundamental principles that were unwritten when the Supreme Court first recognized them. Debates about these principles have pitted members of the Roberts Court’s conservative majority against each other, with even Justice Gorsuch facing an accusation that he has failed at the traditional task of lawfinding. 11Open this footnote Close this footnote 11 Compare Oklahoma v. Castro-Huerta, 142 S.Ct. 2486, 2504 (2022) (Kavanaugh, J., writing for the Court) (“[Justice Gorsuch’s] dissent employs extraordinary rhetoric in articulating its deeply held policy views . . . . But this Court’s proper role under Article III of the Constitution is to declare what the law is, not what we think the law should be.”), with id. at 2505 (Gorsuch, J., dissenting) (“Where our predecessors refused to participate in one State’s unlawful power grab at the expense of the Cherokee [Nation], today’s Court accedes to another’s.”). …Open this footnote Close

Can the Roberts Court find federal Indian law? The answer, I think, is “no,” if by finding law, we mean a process of decisionmaking that makes no normative judgments but instead engages in an empirical survey of written texts, common law decisions, and customary practices. Any effort to find federal Indian law should take seriously the overflowing well of its sources, including treaties and other agreements between tribal nations and the United States, the Constitution, statutes, regulations, executive orders, judicial decisions, customs, and practices, not to mention tribal laws. Selecting among these sources, and deciding which to treat as authoritative, is no mean task.

In some opinions, most notably Haaland v. Brackeen, the Roberts Court has recognized the seriousness of the problem. 12Open this footnote Close this footnote 12 See 143 S.Ct. 1609, 1627-29 (2023). …Open this footnote Close In others, particularly Oklahoma v. Castro-Huerta and Arizona v. Navajo Nation, the Roberts Court has published opinions in the style of a modest science of lawfinding that are actually manifestos for radical legal change. 13Open this footnote Close this footnote 13 See generally 142 S.Ct. at 2504; 143 S.Ct. 1804, 1813-14 (2023) (concluding that no “duty on the United States to take affirmative steps to secure water for the Tribe” could be found in positive law). …Open this footnote Close This science, I will argue, fails as an exercise in lawfinding and as a theory of legal change in federal Indian law. 14Open this footnote Close this footnote 14 On the distinction between law as a “normal science” and moments of a “paradigm shift,” see Hanoch Dagan, The Real Legacy of American Legal Realism, 38 Oxford J. Legal Stud. 123, 134-35 (2018). …Open this footnote Close

My argument proceeds in three parts. Part I sketches the Roberts Court’s renewed interest in lawfinding through the lens of Loper Bright. Part II focuses upon the problem of sources. It maps the multiple modes of the Roberts Court’s Indian law jurisprudence, which show that the Court has no settled answer to the fundamental question of the role of the Article III “judicial Power” 15Open this footnote Close this footnote 15 U.S. Const. art. III, § 1. …Open this footnote Close in federal Indian law. Part III builds upon this description of the sources of federal Indian law and the role of the federal courts as it focuses upon the problem of legal change. It discusses Castro-Huerta and Arizona v. Navajo Nation, which radically changed the law by changing the sources that the Court searched for authoritative rules of decision. In both cases, the Court did not treat the judicial task as one of working through “the seeming commands of the authorities and the felt demands of justice.” 16Open this footnote Close this footnote 16 .Karl N. Llewellyn, The Common Law Tradition: Deciding Appeals 37-38 (1960). …Open this footnote Close It was none other than Justice Gorsuch—the “lawfinder” of Loper Bright—who dissented and gave voice to the impulse to harmonize “vision with tradition,” 17Open this footnote Close this footnote 17 See id. at 37; see also Dagan, supra note 14, at 136 (arguing that legal realists understood adjudication, “at its best,” in these terms). …Open this footnote Close recognizing that finding federal Indian law requires more than modest legal science.

I. Finding Law in Loper Bright

Judicial independence, Chief Justice Roberts wrote in his 2024 year-end report, is America’s gift to the “art of government.” 18Open this footnote Close this footnote 18 Actually, Chief Justice Roberts’ former boss, Chief Justice Rehnquist, wrote those words, which his successor quoted. Chief Justice John Roberts, 2024 Year End Report on the Federal Judiciary 3 (Dec. 31, 2024) [hereinafter Roberts Report] (quoting William H. Rehnquist, Judicial Independence, 38 U. Rich. L. Rev.579, 579-80 (2004)), https://perma.cc/‌2W8B-BCTX. …Open this footnote Close Independent judges do not cater to politicians or buckle before them. Rather, independent judges “construe the law with ‘[c]lear heads . . . and honest hearts.’” 19Open this footnote Close this footnote 19 Loper Bright Enters. v. Raimondo, 144 S. Ct. 2244, 2268 (2024) (Roberts, C.J., writing for the Court) (quoting 1 The Works of James Wilson 363 (J. DeWitt Andrews ed. 1896)). …Open this footnote Close

Call this the Friday Night Lights theory of judging. 20Open this footnote Close this footnote 20 As contrasted with the just-calling-balls-and-strikes theory. See Confirmation Hearing on the Nomination of John G. Roberts, Jr. to be Chief Justice of the United States: Hearing Before the S. Comm. on the Judiciary, 109th Cong. 56 (2005) (statement of John G. Roberts, Jr., J., D.C. Cir.). In Friday Night Lights, a TV drama about high-school football in small town Texas, Coach Eric Taylor inspires his players with a saying: “clear eyes, full hearts, can’t lose.” See Emily St. James, Friday Night Lights’ Jason Katims on the Long Life of “Clear Eyes, Full Hearts, Can’t Lose,” Vox, Mar. 29, 2018, https://perma.cc/‌7X4G-MKCK. …Open this footnote Close After Loper Bright, it is the law of the land. 21Open this footnote Close this footnote 21 Loper Bright, 144 S. Ct. at 2273 (“Courts must exercise their independent judgment in deciding whether an agency has acted within its statutory authority, as the APA requires.”). …Open this footnote Close Indeed, according to Chief Justice Roberts’ opinion in Loper Bright, it has always been the law: The original understanding was that Article III “courts must exercise their independent judgment” when construing the law. 22Open this footnote Close this footnote 22 Id. at 2262. …Open this footnote Close

Independent judges construe written law to find the best reading. Every statute has—”in fact, must” have 23Open this footnote Close this footnote 23 Id. at 2266 (emphasis added). Must it, though? See Ryan D. Doerfler, Can a Statute Have More Than One Meaning?, 94 N.Y.U. L. Rev. 213, 228-42 (2019) (arguing that a statute can have more than one meaning). …Open this footnote Close —a “single, best meaning.” 24Open this footnote Close this footnote 24 Loper Bright, 144 S. Ct. at 2266. …Open this footnote Close The judge’s job is to find it. To do so requires “independent judgment,” not deference to another’s (say, an administrative agency’s) interpretation. 25Open this footnote Close this footnote 25 Id. at 2261-62 (holding that APA requires reviewing courts to “exercise independent judgment,” not to defer to agency constructions of ambiguous statutes). …Open this footnote Close That is the holding of Loper Bright and a statement of confidence in judicial competence. 26Open this footnote Close this footnote 26 Namely, the Roberts Court’s competence, not the competence of the Burger Court that decided Chevron. See id. at 2273 (overruling Chevron U.S.A. Inc. v. Nat. Res. Def. Council, 467 U.S. 837 (1984)). …Open this footnote Close

But what is the independent judge to do when they conclude that the written law does not answer the question before them? Here too, Loper Bright suggests, the independent judge must confidently try to find the law, not make it up. According to Loper Bright, Chevron was a judge-made “fiction” at odds with the true meaning of the Administrative Procedure Act, not mention Marbury v. Madison, the urtext of judicial review. 27Open this footnote Close this footnote 27 Id. at 2268; see id. at 2257 (“Chief Justice Marshall famously declared that ‘[i]t is emphatically the province and duty of the judicial department to say what the law is.’”) (quoting Marbury v. Madison, 5 U.S. (1 Cranch) 137, 177 (1803)); id. at 2261 (“The APA . . . codifies for agency cases the unremarkable, yet elemental proposition reflected by judicial practice dating back to Marbury: that courts decide legal questions by applying their own judgment.”). …Open this footnote Close The Loper Bright Court held that the APA, which directs reviewing courts to decide “all relevant questions of law,” 28Open this footnote Close this footnote 28 5 U.S.C. § 706. …Open this footnote Close requires them to do so independently without deferring to the agency under Chevron. 29Open this footnote Close this footnote 29 Loper Bright, 144 S. Ct. at 2265-66. …Open this footnote Close In this, the APA codified the “traditional understanding” of the Article III “judicial Power,” which is a power to exercise judgment to decide cases. 30Open this footnote Close this footnote 30 Id. at 2262. …Open this footnote Close

Among its many striking features, Loper Bright held that rules of statutory interpretation like Chevron are law—that is, they have stare decisis effect. 31Open this footnote Close this footnote 31 See Gluck, supra note 10, at 32 (“Loper Bright treats Chevron as a precedent—as conmon law to be overruled.”). …Open this footnote Close That is why Chief Justice Roberts’s opinion had to address at length the grounds for dispensing with stare decisis. 32Open this footnote Close this footnote 32 See Loper Bright, 144 S. Ct. at 2270. …Open this footnote Close Thus, Chevron was part of the positive law for interpreting agency-administered statutes, at least until Loper Bright overruled it.

Thus, in treating the law for interpreting statutes as a body of positive law, and in tracing the requirement of “independent judgment” to the APA and the original understanding, the Roberts Court implied that that judges must find law, including law that constrains how they will construe the law.

Lurking here are knotty, longstanding questions of jurisprudence, including questions about what counts as “the law” that is being construed and what the status of methods for construing law is given pervasive disagreement about them. 33Open this footnote Close this footnote 33 See, e.g., H.L.A. Hart, The Concept of Law 3, 273-74 (3d ed. 2012); Ronald Dworkin, Law’s Empire 3-11 (1986). …Open this footnote Close There has been something of a revival in the idea of finding law in recent years. Erie, it seems, may have been “wrong.” 34Open this footnote Close this footnote 34 See Sachs, supra note 1, at 530 (arguing that if Erie is interpreted to deny that lawfinding is possible, “then Erie is wrong”). …Open this footnote Close Finding law is possible. And it is desirable. Trying to find law, rather than make it, wields judicial power modestly: Indeed, it might be thought to define the “judicial Power” in Article III. 35Open this footnote Close this footnote 35 Cf. Loper Bright, 144 S. Ct. at 2277 (Gorsuch, J., concurring) (suggesting that the Framers meant to refer to the idea of “lawfinding” “when they spoke of the ‘judicial Power’”). …Open this footnote Close It is desirable too because it may bring coherence to the doctrine, especially in the hard cases of constitutional law that occupy so many pages of the federal reporters and the law reviews.  36Open this footnote Close this footnote 36 Danielle D’Onfro & Daniel Epps, The Fourth Amendment and General Law, 132 Yale L.J. 910, 945 (2023). …Open this footnote Close

That is not to suggest lawfinding is always easy. Stephen Sachs describes the task as analogous to derermining “whether a given outfit would be out of place at an important business meeting, or whether an ordinary English phrase would be rule out-of-bounds in English class.” 37Open this footnote Close this footnote 37 Sachs, supra note 1, at 535. …Open this footnote Close While it takes diligence, “the social facts are ‘out there’ for diligent jurists to find.” 38Open this footnote Close this footnote 38 Id. at 531. …Open this footnote Close One implication is that “[t]he law is one thing, the decisions of courts another.” 39Open this footnote Close this footnote 39 Id. at 532. …Open this footnote Close

Consistent with this last idea, and quoting Edmund Burke, Justice Gorsuch offered criteria which test any exercise of lawfinding that relies upon past cases:

Burke offered five principles for the evaluation of past judicial decisions: “They ought to be shewn; first, to be numerous and not scattered here and there;—secondly, concurrent and not contradictory and mutually destructive;—thirdly, to be made in good and constitutional times;—fourthly, not to be made to serve an occasion;—and fifthly, to be agreeable to the general tenor of legal principles.” 40Open this footnote Close this footnote 40 Loper Bright, 144 S. Ct. at 2277 (2024) (Gorsuch, J., concurring) (quoting Speech of Dec. 23, 1790, in 3 The Speeches of the Right Honourable Edmund Burke 513 (1816)). …Open this footnote Close

For Justice Gorsuch, it followed that Chevron could and should be overruled because it failed to comport with “mainstream currents” in American law as well as “the law” of the APA. 41Open this footnote Close this footnote 41 See id. at 2281. …Open this footnote Close  Chevron deference was not the law but, instead, a “stray and unconsidered disgression” from the path of the law. 42Open this footnote Close this footnote 42 Id. at 2292. …Open this footnote Close

Justice Gorsuch’s link between lawfinding and legal change is telling. Legal commentators, trained in the world that Erie and Chevron made, have called Loper Bright a change in the law—indeed, a radical change. 43Open this footnote Close this footnote 43 See, e.g., Ian Millhiser, The Supreme Court Just Made a Massive Power Grab That it Will Come to Regret, Vox (June 28, 2024), at https://perma.cc/‌76K6-WDBK. Others have suggested that it is not radical at all. See, e.g., Adrian Vermeuele, Chevron by Any Other Name, The New Digest (June 28, 2024), at https://perma.cc/‌V9RC-CLZT (“Please, everyone, take a deep breath. . . . It is entirely possible that much or most of what was (somewhat misleadingly) called ‘Chevron deference’ can be and will be recreated under a different label: ‘Loper Bright delegation.’”). …Open this footnote Close Not so, Justice Gorsuch suggested. The Court was not changing the law so much as it was finding what the law already was. 44Open this footnote Close this footnote 44 Loper Bright, 144 S. Ct. at 2285 (Gorsuch, J., concurring) (“Chevron deference undermines [various] aspects of our settled law.”). …Open this footnote Close

This all seems to suggest that lawfinding is a modest science. Judges who find the law are modest about judicial opinions, including their own, which are “evidence” of the law but not the law itself. The law itself can be written down. It can also be unwritten. The problem of where to look to find the law, especially the unwritten law, is a problem, but a soluble one. 45Open this footnote Close this footnote 45 See Sachs, supra note 1, at 538 (“[T]he mystery dissolves once we remember how good we are at identifying unwritten rules.”). …Open this footnote Close And the project of lawfinding can accommodate itself quite easily to legal change, even the sort of rule reversal that occurred with Loper Bright.

II. The Problem of Sources and the “Judicial Power” in Federal Indian Law

Federal Indian law is full of principles that were unwritten when the Supreme Court first recognized them. The doctrine of discovery is one. 46Open this footnote Close this footnote 46 See, e.g., Johnson v. McIntosh, 21 U.S. (8 Wheat.) 543, 573 (1823). …Open this footnote Close The Court did not say it was creating this doctrine, but rather purported to find it. The plenary power doctrine is another example of an unwritten principle. Not surprisingly, one modern criticism is that the plenary power doctrine is something judges made up. 47Open this footnote Close this footnote 47 See, e.g., Haaland v. Brackeen, 143 S. Ct. 1609, 1662 (2023) (Thomas, J., dissenting) (arguing that plenary power was “born of loose language and judicial ipse dixit”). …Open this footnote Close

The sources of federal Indian are myriad. Cohen’s Handbook of Federal Indian Law is worth quoting at length on this point:

Researching a federal Indian law issue may require reference to multiple sources of law extending over a broad span of time. In any given case, these sources may encompass federal, state, and tribal law, and require reference to treaties that both predate and postdate the United States Constitution, federal laws adopted as long ago as the first Congress, and tribal law of ancient or recent origin. . . .

The sources of federal Indian law include the United States Constitution, principles of international law, treaties with Indian tribes, federal statutes and regulations, executive orders, and judicial opinions. Consulting the laws of specific tribes governing the resolution of disputes involving Indians and their territory may be necessary to resolve some disputes. Tribal law may also serve as the contextual background informing the development of specific doctrines in federal Indian law. 48Open this footnote Close this footnote 48 .Cohen’s Handbook of Federal Indian Law § 1.04 (Nell Jessup Newton & Kevin Washburn, eds. 2025). …Open this footnote Close

These many sources raise hard questions, including which sources are authoritative for any particular legal issue, how to resolve conflicts among sources over time, how to decide when to consult unwritten customs and practices in addition to or in the absence of written law, and, obviously and importantly, whose customs or practices to consult.

This Part shows that solving these problems is not easy. Much of the difficulty stems from the sheer multiplicity and number of sources. But, as we shall see, some of the difficulty stems from the changes over time in how lawyers think about what counts as a legitimate source of law and the persistence of techniques of legal reasoning from, among others, the once (and future?) world of lawfinding.

A. Constitutional Interpretation and Law from the Atmosphere

Plenary power began as an unwritten principle of sovereignty that the Court found outside the U.S. Constitution. In the earliest case, United States v. Kagama, the Court had to decide whether the Major Crimes Act (MCA), a federal statute, was within Congress’s authority to enact. 49Open this footnote Close this footnote 49 See United States v. Kagama, 118 U.S. 375, 376 (1886). …Open this footnote Close The Court concluded that the plenary power was a sufficient basis for the Act. 50Open this footnote Close this footnote 50 Id. at 383 (holding that the MCA was “within the competency of Congress”). …Open this footnote Close This plenary power was not contained in the Constitution. Rather, it was an incident of sovereignty. A general principle of the law was that sovereigns own their territories, “and the right of exclusive sovereignty which must exist in the National Government” provided Congress with authority to enact criminal law for Indian lands, which were “within the geographical limits of the United States.” 51Open this footnote Close this footnote 51 Id. at 379-80. …Open this footnote Close

More recent cases have insisted that plenary power must be tied to written law. In Haaland v. Brackeen, the Court was especially insistent on this point. 52Open this footnote Close this footnote 52 143 S. Ct. 1609, 1627 (2023). …Open this footnote Close  Erie could not have put the point better: the plenary power doctrine cannot come from “the atmosphere.” 53Open this footnote Close this footnote 53 Id. at 1629. …Open this footnote Close Recognizing that “our precedent is unwieldy, because it rarely ties a challenged statute to a specific source of constitutional authority,” the Roberts Court engaged in a mixture of legal interpretation and lawfinding to tie the plenary power doctrine to the Constitution and conclude that constitutional law constrains its exercise. For example, it interpreted the Indian Commerce Clause and the Treaty Clause as bases for the plenary power doctrine. 54Open this footnote Close this footnote 54 Id. at 1627-28. …Open this footnote Close At the same time, the Court found the plenary power in general principles, namely, “the Constitution’s adoption of preconstitutional powers necessarily inherent in any Federal Government” and the general “trust relationship between the United States and the Indian people.” 55Open this footnote Close this footnote 55 Id. at 1628 (quoting United States v. Curtiss-Wright Export Corp., 299 U.S. 304, 318 (1936) and United States v. Mitchell, 463 U.S. 206, 225-26 (1983)). …Open this footnote Close

Thus, the Roberts Court’s members agree that Congress’s plenary power is something that must be based on more than general notions about sovereignty from the late nineteenth century or judge-made federal common law. At the same time, the Roberts Court relied upon unwritten sources to support its interpretation of the plenary power’s source, scope, and limits in Brackeen. Justice Barrett’s opinion for the Court was frank about the “unwieldy” nature of “our precedent,” which “rarely ties a challenged statute to a specific source of constitutional authority.” 56Open this footnote Close this footnote 56 Id. at 1629. …Open this footnote Close As a result, “it is difficult to categorize cases and even harder to discern the limits on Congress’s power.” 57Open this footnote Close this footnote 57 Id. …Open this footnote Close

Ultimately, Justice Barrett appealed to rule of law values to address the problem of sources, resting upon a normative principle that ruled out the way that the Court approached the problem in Kagama. Contrary to way the Court reasoned in 1886, Justice Barrett stipulated in Brackeen that “[a] power unmoored from the Constitution would lack both justification and limits.” 58Open this footnote Close this footnote 58 Id. at 1627. …Open this footnote Close That is why plenary power could not be left “free-floating” around the “atmosphere,” 59Open this footnote Close this footnote 59 Id. …Open this footnote Close where, one worries, it might someday collide with Swift’s general common law.

B. The General Law and the New Federal Common Law in Federal Indian Law

The criticism that the plenary power doctrine is illegitimate judge-made law has traction in part because of what the Roberts Court has said about federal common law authority. Federal common law, in a word, is “disfavored.” 60Open this footnote Close this footnote 60 Cf. Ashcroft v. Iqbal, 556 U.S. 662, 675 (2009) (stating that implied rights of action, one type of federal common law, are “disfavored”). …Open this footnote Close Summarizing this view, Justice Gorsuch has written that, “[s]ince Erie . . . , federal courts have largely disclaimed the power to develop federal common law outside of a few reserved areas.” 61Open this footnote Close this footnote 61 Turkiye Halk Bankasi A.S. v. United States, 143 S. Ct. 940, 955 (2023) (Gorsuch, J., concurring). …Open this footnote Close Indian affairs has been one of those areas.

While they have worked to ground the plenary power doctrine in constitutional interpretation, the Justices of the Roberts Court have continued to decide federal Indian law cases through common law modes of reasoning. One mode of reasoning looks like Swift’s general common law, while another is the “new federal common law” that followed after Erie. 62Open this footnote Close this footnote 62 See generally Henry J. Friendly, In Praise of Erie—And of the New Federal Common Law, 39 N.Y.U. L. Rev. 383, 384 (1964) (arguing that Erie “cleared the way for the truly uniform federal common law on issues of national concern”). …Open this footnote Close

1. General Law 

Erie did not end reasoning from the general law, if, pace Professor Caleb Nelson, we define that concept as “rules that are not under the control of any single jurisdiction, but instead reflect principles or practices common to many different jurisdictions.” 63Open this footnote Close this footnote 63 Caleb Nelson, The Persistence of General Law, 106 Colum. L. Rev. 503, 505 (2006). …Open this footnote Close Federal courts have continued to apply rules of decision that they justify by pointing to patterns and customs that not written laws adopted by a single sovereign. 64Open this footnote Close this footnote 64 See id. at 506-07. …Open this footnote Close Such uses of general rule—shall we call it the “new federal general common law”?—are common in federal Indian law jurisprudence.

Not long after Erie, in fact, the Supreme Court looked to the general law of trusts as a source of judicially enforceable duties under the Indian trust doctrine. The Indian trust doctrine holds that the United States is a fiduciary for Indians and owes them duties of loyalty and care. In Seminole Nation v. United States, a landmark decision from 1942, the Court cited the Restatement of the Law of Trusts as well as Bogert’s Trusts and Trustees and quoted Meinhard v. Salmon, itself a landmark decision from the New York Court of Appeals, to conclude that the federal executive may have breached fiduciary duties it owed to the Seminole Nation in how it managed Seminole funds. 65Open this footnote Close this footnote 65 316 U.S. 286, 296-97 & n.12 (1942) (citing Restatement (First) of the L. of Trs. § 321 (Am. L. Inst. 1935); 4 George Gleason Bogert, The Law of Trusts and Trustees §§ 901, 955 (1935); and Meinhard v. Salmon, 164 N.E. 545, 546 (N.Y. 1942)). …Open this footnote Close None of these sources, of course, were binding positive law for the case, but the Court cited them as evidence of the general law of trusts.

More recently, the Court has looked to find the general law of contracts in cases arising under the Indian Self-Determination and Education Assistance Act (ISDEAA). 66Open this footnote Close this footnote 66 25 U.S.C. § 5301. …Open this footnote Close This Act is the backbone of the modern tribal self-determination era. Through self-determination contracts between the United States and tribal nations, the federal government provides funding to support tribal self-government and tribal government services, such as healthcare. 67Open this footnote Close this footnote 67 See Cherokee Nation v. Leavitt, 543 U.S. 631, 634 (2005). …Open this footnote Close In a series of decisions, the Court has held that the federal government is bound by general principles of contract law to meet its obligations under the ISDEAA contracts, even when congressional appropriations fall short of what is needed to meet all of the government’s contractual obligations. Writing for the Roberts Court in Cherokee Nation v. Leavitt, Justice Breyer used general law to establish a crucial premise of the Court’s holding that the government had an enforceable obligation to pay: He defined the statutory term “contract” by looking to the Restatement (Second) of Contracts, which supported the conclusion that Congress “meant to treat alike promises made under the [ISDEAA] and ordinary contractual promises.” 68Open this footnote Close this footnote 68 Id. at 639 (citing Restatement (Second) of Contracts § 1 (Am. L. Inst. 1981)). …Open this footnote Close

There are other examples and not all of them have led to the conclusion that tribal nations have judicially enforceable rights. In City of Sherrill v. Oneida Indian Nation, for example, Justice Ginsburg wrote for the Court in applying general principles of laches and impossibility to preclude the Oneida Indian Nation of New York from asserting its immunity to state and local taxation through a federal court injunction. 69Open this footnote Close this footnote 69 544 U.S. 197, 217-219 (2005). …Open this footnote Close And in Upper Skagit Indian Tribe v. Lundgren, Justice Thomas wrote a dissenting opinion that drew upon four versions of the Restatement of Foreign Relations Law, treatises, and commentary on the law of nations to argue that there is an in rem exception to tribal sovereign immunity. 70Open this footnote Close this footnote 70 584 U.S. 554, 567-70 (2018) (Thomas, J., dissenting) (citing Hersch Lauterpacht, The Problem of Jurisdictional Immunities of Foreign States, 28 Brit. Y.B. Int’l L. 220, 244 (1951); Francis Wharton, Conflict of Laws § 273 607 (George Parmele ed., 3d ed. 1905); Restatement of Foreign Rels. L. of the U.S. § 71 cmt. c (Am. L. Inst., Proposed Official Draft 1962); Restatement (Second) of Foreign Rels. L. of the U.S. § 68(b) (Am. L. Inst. 1965); Restatement (Third) of Foreign Rels. L. of the U.S. § 455(1)(c) (Am. L. Inst. 1986); and Restatement (Fourth) of Foreign Rels. L. of the U.S. § 456(2) (Am. L. Inst., Tentative Draft No. 2, 2016)). …Open this footnote Close

2. Federal Common Lawmaking

All of this suggests that there is something like the (old) general law in some Roberts Court decisions when written texts run out and the justices purport to find rules of decisions in unwritten law. There is also something like the new federal common law in other Roberts Court decisions, including those involving the implicit divestiture doctrine.

The Burger Court created the implicit divestiture doctrine in Oliphant v. Suquamish Indian Tribe. 71Open this footnote Close this footnote 71 435 U.S. 191, 209 (1978). See generally Alex Tallchief Skibine, Incorporation Without Assimilation: Legislating Tribal Jurisdiction over Nonmembers, 67 UCLA L. Rev. Discourse 166, 171 (2019) (“The implicit divestiture doctrine has its roots with the 1978 Oliphant decision where the Court ruled that Indian tribes had been implicitly divested of the inherent sovereign power to prosecute non-Indians.”). …Open this footnote Close In an opinion by then-Justice Rehnquist, the Burger Court held that Indian tribes may not enforce their criminal laws against non-Indians who violate tribal criminal codes within Indian Country. This limit on federal recognition of tribal criminal jurisdiction was not a written principle of law. That is, the Court was not construing written law that applied to the case but either finding a general principle of law or making new law. Generally, the opinion reads as if the Court was finding law: Justice Rehnquist identified bits and pieces of evidence in a wide variety of sources, including citations to historical practice, treaties that did not apply, and proposed federal legislation that was never enacted. 72Open this footnote Close this footnote 72 See Oliphant, 435 U.S. at 197-199 & n.8. …Open this footnote Close Thus, if anywhere, the implicit divestiture doctrine was somewhere in the “atmosphere.” 73Open this footnote Close this footnote 73 See Haaland v. Brackeen, 143 S.Ct. 1609, 1627 (2023). …Open this footnote Close

Oliphant was a mess as an exercise in lawfinding, much less legal interpretation. This point has been made ably elsewhere. 74Open this footnote Close this footnote 74 See Matthew L.M. Fletcher, Muskrat Textualism, 116 Nw. U. L. Rev. 963, 1014-1015 (2022). …Open this footnote Close Nevertheless, once written down in Oliphant, the implicit divestiture doctrine became the basis for what looks like federal common lawmaking.

Indeed, the Court itself has described applications of the doctrine as federal common law. This happened in United States v. Lara. 75Open this footnote Close this footnote 75 541 U.S. 193, 207 (2004). …Open this footnote Close The background to Lara was Duro v. Reina, which extended Oliphant’s holding to shield nonmember Indians from the criminal jurisdiction of tribes. 76Open this footnote Close this footnote 76 495 U.S. 676, 679 (1990). …Open this footnote Close Congress responded with the Duro-fix, which recognized and reaffirmed the authority of tribal nations to apply their criminal laws to all Indians within their territories. 77Open this footnote Close this footnote 77 25 U.S.C. § 1301(2). …Open this footnote Close In Lara, the Court held that Congress had authority to abrogate Duro’s holding, treating it as “judicially made’ federal Indian law.” 78Open this footnote Close this footnote 78 Lara, 541 U.S. at 207 (quoting Oliphant v. Squamish Indian Tribe, 435 U.S. 191, 206 (1978). …Open this footnote Close

The Court’s most recent application of the implicit divestiture doctrine reads like lawmaking. As the Court explained in United States v. Cooley, the doctrine extends beyond the enforcement of tribal criminal law to the civil jurisdiction of tribal governments. 79Open this footnote Close this footnote 79 United States v. Cooley, 141 S. Ct. 1638, 1643 (2021). …Open this footnote Close The key case was Montana v. United States, which held as a “general proposition” that tribes do not have authority to regulate nonmember activities on fee land within tribal territories. 80Open this footnote Close this footnote 80 Montana v. United States, 450 U.S. 544, 565 (1981). …Open this footnote Close There are two exceptions to this general principle, the second of which permits a tribe to exercise civil jurisdiction in response to threats to the “political integrity, the economic security, or the health or welfare of the tribe.” 81Open this footnote Close this footnote 81 Id. at 566. …Open this footnote Close In Cooley, the Roberts Court applied this second Montana exception to hold that a tribal police officer may “search and detain for a reasonable time any person he or she believes may commit or has committed a crime.” 82Open this footnote Close this footnote 82 Cooley, 141 S. Ct. at 1643. …Open this footnote Close Its opinion reads as an exercise in federal common lawmaking, one that emphasizes the practical need for tribal officers to have this authority and the unworkability of the limits that the lower court had designed. 83Open this footnote Close this footnote 83 See id. at 1643-45. …Open this footnote Close The Court rejected the argument that its role was solely to construe federal cross-deputization statutes to find written law authorizing the tribal police to search and detain individuals. 84Open this footnote Close this footnote 84 Id. at 1645. …Open this footnote Close Rather, it concluded that under Montana, the requisite “authority . . . rests upon a tribe’s retention of sovereignty.” 85Open this footnote Close this footnote 85 Id. …Open this footnote Close

As with the plenary power doctrine, so too with the implicit divestiture doctrine, critics have argued that what is going on is illegitimate federal common lawmaking. 86Open this footnote Close this footnote 86 See Grant Christensen, Article III and Indian Tribes, 108 Minn. L. Rev. 1789, 1794 (2024); Frank Pommersheim, Tribal Courts and the Federal Judiciary: Opportunities and Challenges for a Constitutional Democracy, 58 Mont. L. Rev. 313, 328 (1997). …Open this footnote Close There is an apparent conflict between the Court’s conclusion that Congress’s plenary power to expressly divest tribal nations of jurisdictional authority must be found within the Constitution and the apparent absence of any judicial power to implicitly accomplish the same outcome. As there is no obvious source of law for the implicit divestiture doctrine, the question remains what, if anything, justifies this application of the Article III judicial power to enjoin tribes from applying their own laws within their own federally-recognized territories.

III. The Problem of Legal Change and the Failures of Modest Legal Science

In this Part, I will discuss two cases that show how the problem of sources may become a problem of legal change within federal Indian law. Oklahoma v. Castro-Huerta, which dismissed a centuries-old “general notion” of law and replaced it with a new general notion, was about state authority in Indian Country. 87Open this footnote Close this footnote 87 142 S. Ct. 2486, 2493 (2022) (5-4 decision). …Open this footnote Close  Arizona v. Navajo Nation, which created a new rule for construing the law of obligations, was about the trust responsibility of the federal government to tribal nations. 88Open this footnote Close this footnote 88 143 S. Ct. 1804, 1815-16 (2023). …Open this footnote Close

As exercises in lawfinding, and as opinions purporting to justify radical legal change in the style of a modest science of lawfinding, both were failures. Having made these choices about sources, the Court then treated the questions before it as “straightforward” 89Open this footnote Close this footnote 89 Castro-Huerta, 142 S. Ct. at 2502. …Open this footnote Close ones of applying the law the Court had found. These moves fail on their own terms as exercises in the modest science of lawfinding, for reasons that are made clear by consulting the Burkean criteria that Justice Gorsuch quoted in Loper Bright. Moreover, the Court’s modest science in these federal Indian law cases fails to meet the problem of legal change.

There are, Hanoch Dagan has argued, “two genres of interpretive legal theories”: one for the “day-to-day operation” of law and another for moments that challenge “on-the-wall understandings” of law. 90Open this footnote Close this footnote 90 Hanoch Dagan, Two Genres of Interpretive Legal Theories, in Understanding Private Law: Essays in Honour of Stephen A. Smith 49, 57 (Evan Fox-Decent et al. eds., 2025). …Open this footnote Close The science of the day-to-day operations of law skirts normative debates, and for good reason, as its aim is to be workable without resolving deep disagreements about justice. 91Open this footnote Close this footnote 91 Id. at 55. …Open this footnote Close But the conventional understandings of law can persist for only so long, and when they wear down and are challenged, “the normal science of legal discourse [becomes] . . . useless.” 92Open this footnote Close this footnote 92 Id. at 56. …Open this footnote Close What count as adequate legal reasons for paradigm shifts are different, and require serious engagement with the well-worn conventions and normative arguments challenging them 93Open this footnote Close this footnote 93 See id. at 58 (arguing that legal reasons for paradigm shifts “expose the contingency of the implicit background understandings . . . ; explain why they are mistaken—why they render the existing law normatively indefensible; and offer a different understanding of the very same pedigreed sources and concepts”). …Open this footnote Close —the sort of serious engagement that Justice Gorsuch offered in his dissenting opinions in both Castro-Huerta and Arizona v. Navajo and that, ironically enough, elicited from the Court’s majority the charge that Justice Gorsuch was not taking the task of lawfinding seriously. 94Open this footnote Close this footnote 94 See infra notes 117-119and accompanying text. …Open this footnote Close

A. One General Notion Yields to Another

The question in Oklahoma v. Castro-Huerta was whether a state has authority to prosecute a non-Indian person for a crime committed against an Indian person in Indian Country. 95Open this footnote Close this footnote 95 Oklahoma v. Castro-Huerta, 142 S. Ct. 2486, 2491 (2022). …Open this footnote Close One year before, the Court held in McGirt v. Oklahoma that the State of Oklahoma did not have authority to prosecute an Indian person for a crime committed within the reservation of the Muscogee (Creek) Nation, which was Indian Country. 96Open this footnote Close this footnote 96 140 S. Ct. 2452, 2459 (2020). …Open this footnote Close  McGirt rested upon principles of federal Indian law recognized in Worcester v. Georgia, the third in the Marshall trilogy, a case that, not incidentally, held that the State of Georgia did not have authority to prosecute a non-Indian person for being in Indian Country without permission from the state government. 97Open this footnote Close this footnote 97 See id. at 2476-77(quoting Worcester v. Georgia, 31 U.S. (6 Pet.) 515, 557 (1832)). …Open this footnote Close  Worcester’s holding was based on the principle, which was recognized in a treaty between the Cherokee Nation and the United States, that an Indian tribe “is a distinct community occupying its own territory.” 98Open this footnote Close this footnote 98 Worcester, 31 U.S. (6 Pet.) at 561. …Open this footnote Close  The question presented in Castro-Huerta, in short, was answered by settled law.

Except, apparently, it wasn’t, because the Roberts Court held that the State of Oklahoma had authority to prosecute a non-Indian person for a crime committed within Indian Country. Justice Kavanaugh’s opinion conceded that its holding was inconsistent with the principles of federal Indian law recognized in Worcester. 99Open this footnote Close this footnote 99 See Castro-Huerta, 142 S. Ct. at 2493. …Open this footnote Close No matter, however, because the “general notion” in Worcester was not law. 100Open this footnote Close this footnote 100 Id.(quoting Organized Village of Kake v. Egan 369 U.S. 60, 72 (1962)). …Open this footnote Close

Justice Kavanaugh’s rhetoric trades on the notion, which we have from Erie, that law does not consist of general notions. Law must be based on positive authority. Legal rules must stem from applicable positive law. 101Open this footnote Close this footnote 101 In 1L private law courses, for instance, we say that the Restatements of Law are not actually law. (And then we let students cite the Restatements on their final exams on the law they’ve learned.). …Open this footnote Close The problem with Swift v. Tyson 102Open this footnote Close this footnote 102 41 U.S. (16 Pet.) 1 (1842). …Open this footnote Close was that it placed great stock in notions drawn from general law. Justice Kavanaugh would not make that mistake in Castro-Huerta.

Yet all Justice Kavanaugh did was replace one general notion with another. The notion was that “Indian [C]ountry is part of the State, not separate from the State.” 103Open this footnote Close this footnote 103 Castro-Huerta, 142 S. Ct. at 2493. …Open this footnote Close This notion is the opposite of what Worcester held. 104Open this footnote Close this footnote 104 See 31 U.S. (6 Pet.) at 542, 561-62. …Open this footnote Close

The first, and most telling, citation for Justice Kavanaugh’s general notion was the Tenth Amendment, which he did not quote. 105Open this footnote Close this footnote 105 See Castro-Huerta, 142 S. Ct. at 2493. …Open this footnote Close Citing the Tenth Amendment begs the question in Castro-Huerta. The Tenth Amendment does not actually say that “Indian Country is part of the State, not separate from the State.” It says, “[t]he powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the states respectively, or to the people.” 106Open this footnote Close this footnote 106 .U.S. Const. amend. X. …Open this footnote Close

On the question of whether non-Indian persons in Indian Country are subject to state criminal jurisdiction, Justice Kavanaugh’s opinion reads like a postmodern pastiche of quotations yanked from an hour-long Westlaw search. In six seriatim paragraphs, he presented quotations from six opinions as free-standing statements whose meaning was self-evident (or, one might think, self-evidently empty). 107Open this footnote Close this footnote 107 See Castro-Huerta, 142 S. Ct. at 2493-94. …Open this footnote Close One of these was a dictum from a 1962 decision, to wit, “the ‘general notion drawn from Chief Justice Marshall’s opinion in Worcester v. Georgia’ ‘has yielded to closer analysis.’” 108Open this footnote Close this footnote 108 Id. at 2493 (quoting Organized Village of Kake v. Egan, 369 U.S. 60, 72 (1962)). …Open this footnote Close

Others have shown that none of these cases supported the Roberts Court’s holding that Oklahoma could prosecute a non-Indian for a crime committed against an Indian within the Cherokee reservation. 109Open this footnote Close this footnote 109 Dylan R. Hedden-Nicely, The Reports of My Death Are Greatly Exaggerated: The Continued Vitality of Worcester v. Georgia, 52 Sw. L. Rev. 255, 257-58, 260-68 (2023); Gregory Ablavsky, Too Much History: Castro-Huerta and the Problem of Change in Indian Law, 2022 Sup. Ct. Rev. 293, 318-19, 326-32, 336, 341-343. …Open this footnote Close Indeed, the closest the Court could come was the assertion that an 1882 case, United States v. McBratney, was “the leading case in the criminal context.” 110Open this footnote Close this footnote 110 Castro-Huerta, 142 S. Ct. at 2494 (citing United States v. McBratney, 104 U.S. 621, 623-624, (1882)). …Open this footnote Close Even that case, however, did not hold that a state could prosecute a non-Indian person for a crime against an Indian person within Indian Country, for the simple reason that there was no Indian victim in McBratney. 111Open this footnote Close this footnote 111 See McBratney, 104 U.S. at 624. …Open this footnote Close But, in a classic case of the-exception-becomes-the-rule, McBratney rose to the fore in Castro-Huerta.

Notwithstanding his dismissal of a “general notion” found in Worcester, Justice Kavanaugh’s opinion amounts to a simple shift in the sources to be treated as authoritative sources of general rules of decision. What happened to the original understanding? Superseded, apparently. 112Open this footnote Close this footnote 112 Cf. Castro-Huerta, 142 S. Ct. at 2493 (“[T]he ‘general notion drawn from Chief Justice Marshall’s opinion in Worcester v. Georgia’ ‘has yielded to closer analysis.’”) (quoting Organized Village of Kake, 369 U.S. at 72). …Open this footnote Close The Constitution’s references to Indian tribes? Not mentioned, much less interpreted for what light they might shed on the Tenth Amendment’s relevance for Indian Country. Federal statutes that might be read to codify the original understanding that Indian Country is separate from the states? A few are discussed but interpreted through the lens of the general notion that Justice Kavanaugh took for granted, namely, that Indian Country is not separate from the states. 113Open this footnote Close this footnote 113 Id. at 2494-95. …Open this footnote Close

What about the case law in Castro-Huerta? Justice Kavanaugh failed the test of lawfinding, at least if the test is the one offered by Edmund Burke and repeated by Justice Gorsuch in Loper Bright. 114Open this footnote Close this footnote 114 See Loper Bright Enters. v. Raimondo, 144 S. Ct. 2244, 2277 (2024) (Gorsuch, J., concurring); see also supra note 40 and accompanying text. …Open this footnote Close Justice Kavanaugh’s assemblage of quotations to cases was scattered by design and made no effort to address contradictory opinions. Most strikingly, at least for experts in the field, Justice Kavanaugh did not acknowledge that the two most important case citations in his opinion—McBratney and Organized Village of Kake—were decided in the Allotment and Assimilation Era and the Termination Era, respectively. 115Open this footnote Close this footnote 115 See McBratney, 104 U.S. at 623-624 (Allotment and Assimilation Era); Organized Village of Kake v. Egan, 369 U.S. 60, 72 (1962) (Termination Era). …Open this footnote Close These were, to put it mildly, not “good and constitutional times” 116Open this footnote Close this footnote 116 .Burke, supra note 40, at 513. …Open this footnote Close for the federal government’s treatment of Native people.

Justice Gorsuch, who was joined by Justices Breyer, Sotomayor, and Kagan, dissented from the majority’s methodology and its conclusions. Methodologically, Justice Gorsuch wrote, the Court’s “declaration comes as if by oracle, without any sense of the history recounted above and unattached to any colorable legal authority.” 117Open this footnote Close this footnote 117 Castro-Huerta, 142 S. Ct. at 2511(Gorsuch, J., dissenting). …Open this footnote Close Substantively, “a more ahistorical and mistaken statement of Indian law would be hard to fathom.” 118Open this footnote Close this footnote 118 Id. …Open this footnote Close

“From start to finish,” Justice Kavanaugh replied for the Court, Justice Gorsuch’s “dissent employs extraordinary rhetoric in articulating its deeply held policy views about what Indian law should be.” 119Open this footnote Close this footnote 119 Id. at 2504 (majority opinion). …Open this footnote Close Not just rhetoric, which is bad enough, 120Open this footnote Close this footnote 120 See Aristophanes, The Clouds 92 (William Arrowsmith trans. 1962). …Open this footnote Close but extraordinary rhetoric, the sort of rhetoric unbecoming of a judge who agrees that the judicial task is to find “what the law is.” 121Open this footnote Close this footnote 121 Castro-Huerta, 142 S. Ct. at 2504 (emphasis added). …Open this footnote Close What was so extraordinary about Justice Gorsuch’s rhetoric? Well, “the dissent emphasize[d] the history of mistreatment of American Indians,” and this history, Justice Kavanaugh suggested, was of no matter for the modest science of lawfinding. 122Open this footnote Close this footnote 122 Id. at 2502. …Open this footnote Close

Justice Gorsuch’s dissent considered an array of diverse, and sometimes contradictory, sources across a long arc of history. 123Open this footnote Close this footnote 123 Id. at 2505-11 (Gorsuch, J., dissenting). …Open this footnote Close It began with Cherokee Nation history from before the creation of the American Republic and carried forward an historical story to the Supreme Court’s decision in Denezpi v. United States, which the Court decided “just weeks” before Castro-Huerta. 124Open this footnote Close this footnote 124 See id. at 2505 (Cherokee Nation); id. at 2511 (citing Denezpi v. United States, 142 S. Ct. 1838, 1843(2022)). …Open this footnote Close In Justice Gorsuch’s telling, Worcester’s general principle excluding states from applying their criminal laws in Indian Country could be traced through many legal sources over the centuries. 125Open this footnote Close this footnote 125 Id. at 2511. …Open this footnote Close

Behind this effort to harmonize history was Justice Gorsuch’s frankly expressed sense of justice. As he understood it, the United States had “exile[d]” the Cherokee Nation to Oklahoma, but it made a promise “that [the Nation] would remain forever free from interference by state authorities.” 126Open this footnote Close this footnote 126 Id. at 2505. …Open this footnote Close In Worcester, the Court had worked to hold the United States to its promises to the Cherokee Nation. 127Open this footnote Close this footnote 127 Id. …Open this footnote Close But in Castro-Huerta, it broke that promise. 128Open this footnote Close this footnote 128 See id. …Open this footnote Close

Justice Gorsuch was right that the Court’s majority had made a “category error.” 129Open this footnote Close this footnote 129 Id. at 2511. …Open this footnote Close It was not just a doctrinal error, however. Castro-Huerta was a paradigm-shift masquerading as “normal science.” 130Open this footnote Close this footnote 130 See Dagan, supra note 90, at 60. …Open this footnote Close Justice Kavanaugh presented the holding as a simple application of the already-existing paradigm, not as the paradigm-shift it actually was. The Roberts Court’s jurisprudential failure in Castro-Huerta was to mistake, or, worse, to refuse to acknowledge, that its decision was a radical reversal from the day-to-day operation of federal Indian law.

B. You Didn’t Think That “Trust” Really Meant Trust, Did You? 

Justice Kavanaugh also wrote for the Roberts Court in Arizona v. Navajo Nation in an opinion that repeated the same jurisprudential errors. 131Open this footnote Close this footnote 131 143 S. Ct. 1804 (2023). …Open this footnote Close The case was about the rights of the Navajo Nation to water from the Colorado River. 132Open this footnote Close this footnote 132 Id. at 1811-12. …Open this footnote Close The issue was not whether the Navajo Nation has rights in those waters. The issue instead was quantifying the water rights that the Navajo Nation reserved through its treaties with the United States. 133Open this footnote Close this footnote 133 See id. at 1819 (Gorsuch, J., dissenting) (describing the Navajo Nation’s complaint). …Open this footnote Close

For decades in the twentieth century, the federal government litigated against western states about the Navajo water rights while successfully opposing the Navajo Nation government’s motions to intervene. 134Open this footnote Close this footnote 134 Id. at 1823-24 (Gorsuch, J., dissenting). …Open this footnote Close In Winters v. United States, a 1908 decision involving water rights to support the Fort Belknap Indian Reservation, the Court held that the reservation of Indian lands implies the reservation of surface water rights to support the Indian reservation. 135Open this footnote Close this footnote 135 207 U.S. 564, 575-77 (1908). …Open this footnote Close Since at least the 1960s, the Navajo Nation has been trying to get a judicial quantification of its reserved rights to the Colorado River. 136Open this footnote Close this footnote 136 Arizona, 143 S. Ct. at 1824 (Gorsuch, J., dissenting). …Open this footnote Close Without it, there is a significant risk that plans about the Colorado River will divert Navajo water to non-Navajo people. Given the acute water crisis on the Navajo Nation, where approximately 30 percent of homes do not have running water, 137Open this footnote Close this footnote 137 Navajo Water Project, About the Project, https://perma.cc/‌VS93-3N44. …Open this footnote Close this risk of loss of water rights threatens Navajo families.

Because the federal government had resisted quantification of the Navajo rights, the Nation sued under the APA for injunctive and declaratory relief to obtain an accounting of its rights to Colorado River water. The Ninth Circuit held that the Navajo Nation could plead a claim for an accounting of its rights and that the APA provided a right of action for equitable relief to order the federal government to quantify the water rights. 138Open this footnote Close this footnote 138 See Navajo Nation v. U.S. Dep’t of Interior, 26 F.4th 794, 803-04, 808-09, 812-14 (9th Cir. 2022). …Open this footnote Close

The Roberts Court reversed and held that there was no legal basis for the relief that the Navajo Nation requested. 139Open this footnote Close this footnote 139 Arizona, 143 S. Ct. at 1816. …Open this footnote Close Writing for the Court, Justice Kavanaugh construed the complaint as requesting “affirmative steps” from the United States to protect Navajo water rights and found no legal source of any obligation to take such steps. 140Open this footnote Close this footnote 140 Id. at 1810. …Open this footnote Close To impose an affirmative obligation on the federal government without a basis in positive law would be to veer from the Court’s “constitutional lane.” 141Open this footnote Close this footnote 141 Id. at 1814. …Open this footnote Close

Deference to the democratically accountable branches and positivism were the two main themes of Justice Kavanaugh’s opinion. 142Open this footnote Close this footnote 142 See id. at 1814. …Open this footnote Close Water rights are complex and a hot button issue in the West. It follows, Justice Kavanaugh reasoned, that the political branches should decide disputes about them. 143Open this footnote Close this footnote 143 Id. …Open this footnote Close Judicially enforceable obligations to tribal nations must exist in positive law. The general trust relationship between the United States and tribal nations is not enough to establish a legal duty that a federal court may enforce. 144Open this footnote Close this footnote 144 Id. at 1813. …Open this footnote Close Nor are general principles of trust law enforceable against the United States when it acts as a trustee for tribes—as the Court acknowledged the United States is doing with respect to the Navajo Nation’s water rights. 145Open this footnote Close this footnote 145 See id. at 1813 n.1. …Open this footnote Close Rather, the federal government’s judicially enforceable obligations must be found, if at all, in specific provisions of positive law.

Moreover, the federal government’s positive legal obligations must be express. That is, a tribe suing the federal government must show that the United States has “expressly accepted” an obligation in a “treaty, statute, or regulation.” 146Open this footnote Close this footnote 146 Id. at 1813 (quoting United States v. Jicarilla Apache Nation, 564 U.S. 162, 177 (2011)). …Open this footnote Close Judges should not be implying obligations from the purposes of positive enactments or creating obligations that are not express in those enactments.

The Navajo Nation’s APA suit failed this test. 147Open this footnote Close this footnote 147 Id. at 1814.. …Open this footnote Close The 1868 Treaty, which the Nation emphasized, did not expressly require “affirmative steps” from the United States, at least with respect to water from the Colorado River. 148Open this footnote Close this footnote 148 Id. at 1810. …Open this footnote Close And the Court would not imply an “affirmative” obligation from the purposes of the 1868 Treaty. 149Open this footnote Close this footnote 149 Id. at 1814. …Open this footnote Close Rather, it would defer to the political branches’ decisions about how to implement the treaties and the United States’ trust responsibility to the Navajo Nation.

Justice Kavanaugh’s opinion treated the case as one of the straightforward application of settled principles. But the rule of decision he applied cannot be traced to any specific provision of the constitution or a treaty, statute, or regulation. Justice Gorsuch pointed this out in his dissenting opinion, to no avail. 150Open this footnote Close this footnote 150 See id. at 1830-31 (Gorsuch, J., dissenting). …Open this footnote Close

Prior to Arizona v. Navajo Nation, the Supreme Court had never held that a tribal nation suing the federal executive branch for equitable relief under the APA had to identify a specific provision of positive law that “expressly accepted” an obligation to the tribe. The APA, which played such an important role in Loper Bright but which Justice Kavanaugh never cited in his opinion for the Court, provides a right of action and waives sovereign immunity for suits for equitable relief against federal agencies. 151Open this footnote Close this footnote 151 See 5 U.S.C. § 702. …Open this footnote Close It expressly authorizes judicial relief for agency action “unlawfully withheld.” 152Open this footnote Close this footnote 152 Id. § 706. …Open this footnote Close Nowhere in the APA does it state that a suit for equitable relief to require an agency to act must be based upon an express requirement in a treaty, statute, or regulation. 153Open this footnote Close this footnote 153 See 5 U.S.C. §§ 702, 704, 706. …Open this footnote Close Thus, even if one accepts Justice Kavanaugh’s framing of the Navajo Nation’s complaint—that it was demanding “affirmative steps” from the federal executive branch—the APA provided a right to sue for unlawfully withheld action.

In fact, the Navajo Nation’s complaint was a paradigmatic one in equity. All nine members of the Roberts Court agreed that the United States was a trustee of the reserved water rights of the Navajo Nation. 154Open this footnote Close this footnote 154 See Arizona, 143 S. Ct. at 1814; id. at 1829 (Gorsuch, J., dissenting). …Open this footnote Close They also all acknowledged that the United States executive branch was making decisions about the potential future allocation of water from the Colorado River, which would impact the exercise of those rights. And, as all recognized, the federal executive branch was making those decisions about a trust asset without ever quantifying the value of the asset. 155Open this footnote Close this footnote 155 Id. at 1812-13 (majority op.); id at 1824 (Gorsuch, J., dissenting). …Open this footnote Close

To put it plainly, that is not how a trustee is supposed to manage a trust asset. Compare, for example, the Navajo Nation’s request for a quantification of its water rights to an equitable action for accounting. Equity provides the beneficiary of a trust the right to sue for an accounting of the trust assets. The equitable action for an accounting has a centuries-long history, 156Open this footnote Close this footnote 156 See Joshua Getzler, Rumford Market and the Genesis of Fiduciary Obligations, in Mapping the Law: Essays in Memory of Peter Birks 577, 580 (Andrew Burrows & Alan Rodger eds. 2006). …Open this footnote Close and is not a disfavored action that requires specific and express authorization in law. To the contrary, the purpose of equitable relief is to provide for a remedy when law has run out, that is, when there is no adequate remedy at law. Elsewhere, the Roberts Court has recognized this basic point of equitable practice and said that equity’s historical role is an important guide to equity today. 157Open this footnote Close this footnote 157 See, e.g., US Airways, Inc. v. McCutchen, 569 U.S. 88, 94-95 (2013) (citing Mertens v. Hewitt Associates, 508 U.S. 248, 256 (1993)); eBay Inc. v. MercExchange, L.L.C., 547 U.S. 388, 391 (2006). …Open this footnote Close

Thus, the “expressly accepted” requirement is not to be found either in the APA, which expressly authorized the suit but which Justice Kavanaugh did not cite, or in equity, which provides for the remedy that the Navajo Nation was seeking. Here too, if Loper Bright is any guide, the Roberts Court failed the lawfinding test.

Justice Kavanaugh’s opinion cited neither the APA nor equitable decisions, which were both applicable sources of law, but instead cited snippets of text from an opinion involving Rule 501 of the Federal Rules of Evidence and a few opinions applying the Indian Tucker Act, a statute that applies only to actions seeking damages, a form of legal not equitable relief. 158Open this footnote Close this footnote 158 Arizona, 143 S. Ct. at 1812-14 (citing United States v. Jicarilla Apache Nation, 564 U.S. 162, 173-174, 177-178 (2011); United States v. Navajo Nation, 537 U.S. 488, 506-507 (2003); and United States v. Mitchell, 445 U.S. 535, 542, 546 (1980)). …Open this footnote Close Only one of these opinions—the one applying the Federal Rule of Evidence to figure out the scope of the attorney-client privilege between the Department of Justice and the Department of the Interior—contained the “expressly accept[ed]” statement that became the rule of decision in Arizona v. Navajo Nation. 159Open this footnote Close this footnote 159 Jicarilla Apache Nation, 564 U.S. at 177. …Open this footnote Close The other opinions interpreting the Indian Tucker Act did refer to the need for a tribe suing for damages to point to a specific provision of positive law. 160Open this footnote Close this footnote 160 See Navajo Nation, 537 U.S. at 506; Mitchell, 445 U.S. at 542, 546. …Open this footnote Close This was because a tribe suing for damages—unlike a tribe suing under the APA—needs a waiver of sovereign immunity under the Indian Tucker Act. 161Open this footnote Close this footnote 161 28 U.S.C. §§ 1491, 1505. …Open this footnote Close But even the Indian Tucker Act cases say that as long as the tribe has pointed to specific provisions that make the United States the trustee of a tribal resource and create rights or impose duties, the courts must specify the fiduciary obligations of the federal government by reference to general principles of trust law and may “infer[]” the “availability” of damages remedies. 162Open this footnote Close this footnote 162 Navajo Nation, 537 U.S. at 506; United States v. White Mountain Apache Tribe, 537 U.S. 465, 475-76 (2003); United States v. Mitchell, 463 U.S. 206, 226-27 (1983). …Open this footnote Close In the end, then, Justice Kavanaugh’sbest evidence for the “expressly accepted” requirement was a single sentence applying the federal rules of evidence in an opinion about the government’s attorney-client privilege. 163Open this footnote Close this footnote 163 In its limitations on the Indian trust doctrine, Justice Kavanaugh’s opinion shares something with Justice Thomas’s radical critique of the trust responsibility and the Indian canons of construction. In his concurring opinion in Arizona v. Navajo Nation, Justice Thomas argued that the general principle that the United States is a trustee for Native people is not a valid source of legal rules. Arizona, 143 S. Ct. at 1817-18 (Thomas, J., concurring). …Open this footnote Close

The obvious question is why a statement in an opinion about an evidentiary privilege, one that involved the express common law authority in FRE 501, should control the availability of equitable relief under the APA. Justice Kavanaugh answered that question with a footnote that cited the separation of powers. 164Open this footnote Close this footnote 164 Arizona, 143 S.Ct. at 1813 n.1 (majority op.). …Open this footnote Close Thus, it appears, the Roberts Court found a rule of decision in a sentence of an opinion about the attorney-client privilege that, it has turned out, is based on the structure of the constitution and therefore applies whenever a tribe seeks relief, whether legal or equitable, against the federal executive branch.

In the traditional understanding of lawfinding, recall from Justice Gorsuch’s opinion in Loper Bright, judges did not find law from a single opinion. 165Open this footnote Close this footnote 165 Loper Bright Enters. v. Raimondo, 144 S. Ct. 2244, 2276 (2024) (Gorsuch, J., concurring). …Open this footnote Close Rather, law consisted of general principles and customary practices that had to be proven through multiple sources of evidence. Any single opinion could err in its restatement of those principles or practices. A judge setting out to find law would therefore be cautious about staking too strong a claim based on any one opinion. But that is precisely what Justice Kavanaugh did in Arizona v. Navajo Nation. His opinion staked a strong claim about the separation of powers based on a statement in a single opinion. It then applied a rule of decision based upon that claim even though it was inconsistent with multiple other pieces of evidence, including the APA’s text and general principles of equity that have been restated for centuries.

In his dissenting opinion, Justice Gorsuch again identified the paradigm-shift that the Court had accomplished by shifting the sources it would treat as authoritative. 166Open this footnote Close this footnote 166 Arionza, 143 S. Ct. at 1831 (Gorsuch, J. dissenting). …Open this footnote Close As he saw it, the Navajo Nation’s case had to be understood within the long and tortured history of the Nation’s relations with the United States. 167Open this footnote Close this footnote 167 Id. at 1824 (Gorsuch, J. dissenting) (“With a view of this history, the proper outcome of today’s case follows directly.”). …Open this footnote Close And again, as in Castro-Huerta, Justice Gorsuch sought to harmonize the doctrinal authorities and a felt sense of justice, hoping that, the Court’s holding notwithstanding, “some measure of justice will prevail in the end.” 168Open this footnote Close this footnote 168 Id. at 1833 (Gorsuch, J., dissenting). …Open this footnote Close

Conclusion

Perhaps justice will indeed prevail. That is, one possible lesson of the Roberts Court’s federal Indian law jurisprudence is that the legacy of the legal realists still holds sway, all the talk of lawfinding notwithstanding. If nothing else, it is striking to hear echoes of Karl Llewelyn’s talk of “the felt demands of justice” in Justice Gorsuch’s hopes of “some measure of justice.” 169Open this footnote Close this footnote 169 Compare Llewellyn, supra note 16, at 38, with Arizona, 143 S. Ct. at 1833 (Gorsuch, J., dissenting). …Open this footnote Close

There are other possibilities. Perhaps the lesson of the Roberts Court’s jurisprudence is that we have never been as modern as Erie told us we were. 170Open this footnote Close this footnote 170 Cf. Bruno Latour, We Have Never Been Modern 10-12 (Catherine Porter, trans. 1993). …Open this footnote Close Or, for a third, more troubling possibility, perhaps modernity is a choice, and the right to choose is part of what the Roberts Court is celebrating with its “independent judgment.” 171Open this footnote Close this footnote 171 Loper Bright, 144 S. Ct. at 2262. …Open this footnote Close

* Professor of Law, University of California, Berkeley School of Law. I want to thank Greg Ablavsky, Jud Campbell, Hanoch Dagan, Judge William Fletcher, José Argueta Funes, Michael McConnell, and Liz Reese for helpful comments and conversations, as well as participants at the Stanford Law Review’s 2025 symposium and at the Berkeley Law Faculty Workshop for their helpful feedback.