abstract. American immigration law is a domain where ordinary constitutional rules have never applied. At least, that is the conventional wisdom. Immigration law’s exceptionalism is widely believed to flow directly from the Supreme Court’s invention, in the late nineteenth century, of the so-called plenary power doctrine. On the standard account, that doctrine has long insulated immigration policies from constitutional scrutiny. The plenary power doctrine is thought to permit everything from President Trump’s Muslim ban to the indefinite detention of migrants at the border.

But the reigning historical account of immigration exceptionalism is wrong. Revisiting the field’s canonical cases, this Article reveals that the plenary power doctrine lawyers and judges argue over today was not created in a series of late nineteenth-century cases. Far from being exceptional, those cases applied the then-standard framework linking due process and the separation of powers. By failing to understand that nineteenth-century immigration law was ordinary public law, scholars and jurists have, for decades, badly misunderstood immigration law’s foundational cases. We have also overlooked the role that immigration law played in the development of modern public law. At the turn of the twentieth century, immigration law evolved apace with the rest of public law as both underwent a dramatic transformation. In some cases, immigration law even led the revolution, driving the development of the legal regime we now call “administrative law.”

Immigration exceptionalism is thus a recent invention. Indeed, it might be more accurate to say that the immigration plenary power doctrine was invented in the Roberts Court rather than in the late nineteenth century. Once we locate immigration exceptionalism in its proper moment, we can better appreciate immigration law’s centrality to the development of American public law. We can also assemble new arguments against the modern exceptionalism that is responsible for the very worst parts of immigration law today.

author. Robert A. Kindler Professor of Law, New York University School of Law. I am grateful to Greg Ablavsky, Paulina Arnold, Ahilan Arulanantham, Maggie Blackhawk, Curt Bradley, Jennifer Chacón, Jonathan Hafetz, David Hausman, Scott Hemphill, Mary Hoopes, Daryl Levinson, Emma Kaufman, Deborah Malamud, Hiroshi Motomura, Caleb Nelson, Gerry Neuman, Daphna Renan, Cristina Rodríguez, Noah Rosenblum, Bijal Shah, and the participants in NYU’s faculty workshop for their generous comments; to David Golove, Dan Hulsebosch, David Strauss, and others for encouraging this project in its earliest stages; and to the many students I have taught in my immigration law course, where the ideas in this paper were first incubated. For tremendous research assistance, I want to thank David Blitzer, Michele Chu, Jessica Coffrin-St. Julien, Hillary Coleman, Lily Gutterman, Yvonne Diabene, Maxwell Jenkins-Goetz, Meena Roldán Oberdick, Tessa Ruff, and Sarah Taitz.

Introduction

American immigration law is an area where ordinary constitutional rules have never applied. At least, that is the conventional wisdom. Immigration law’s exceptionalism is widely believed to flow directly from the Supreme Court’s invention, in the late nineteenth century, of the so-called plenary power doctrine. On the standard account, that doctrine has long insulated immigration policies from ordinary constitutional scrutiny—perhaps from meaningful judicial review altogether.1 Immigration law’s resulting exceptionalism is widely believed to permit everything from a ban on Muslim immigrants to the complete denial of due process to asylum seekers.2

This seductive account of immigration law’s exceptionalism—that it is an ancient doctrine marking immigration as a constitutionally exceptional sphere—has been embraced by lawyers and scholars of all stripes. Perhaps it should be no surprise that government lawyers, regardless of the presidential administration, routinely invoke the plenary power doctrine when seeking to defeat constitutional claims brought by noncitizens. But these government lawyers are hardly alone. Even lawyers and scholars who are deeply critical of the doctrine nonetheless accept its status as a bedrock principle invented in the Supreme Court’s canonical Chinese exclusion cases.3 That is why, when then-candidate Donald Trump first announced his plan to ban Muslim immigrants, many scholars who wrote opinion pieces decrying the policy nonetheless concluded that it would be perfectly constitutional for the President to exclude immigrants on the basis of their religious beliefs.4

This Article argues that the reigning historical account of immigration exceptionalism is wrong.5 Revisiting the field’s canonical cases, I will show that the immigration plenary power that lawyers and judges argue over today was not created in a series of late nineteenth-century cases. Far from being exceptional, those cases simply applied the then-standard framework linking due process and the separation of powers. In nineteenth-century American public law, due process was understood to be, in essence, a separation-of-powers requirement—separating judicial functions that could be performed only by a court from those functions that could properly be undertaken by the legislature or by executive-branch officials. And the key to unlocking that old separation-of-functions puzzle was the then-dominant distinction between privileges and private rights. That distinction determined when Congress could interfere with a person’s legal interests, when due process was owed, and when disputes could be adjudicated by executive-branch officials rather than an Article III court. Crucially, immigration law’s foundational cases were all litigated and resolved within this traditional framework. By failing to understand that nineteenth-century immigration law was ordinary public law, scholars and jurists have, for decades, badly misunderstood immigration law’s foundational cases.6

We have also overlooked the role that immigration law played in the development of American public law. Contrary to conventional wisdom, the constitutional approach that the Supreme Court applied in late nineteenth-century immigration cases did not stick with us all the way to the present. Indeed, it lasted less than two decades. At the dawn of the twentieth century, American public law underwent an enormous transformation. The Supreme Court, confronting the explosive growth of the administrative state and myriad other legal and political forces, cast aside nineteenth-century ideas about due process and the separation of powers that had, for so long, organized public law. In place of that old approach, the Court created an entirely new framework for thinking about the role federal courts would play in policing executive-branch officers. Crucially, immigration law during this period evolved apace with the rest of public law; it underwent the same dramatic transformation taking place elsewhere. Indeed, immigration law was often on the leading edge of the transformation, driving the development of the legal regime we now call “administrative law.” This transformative period, most of which is missing in modern accounts of the immigration plenary power, supplies additional evidence of the anti-exceptionalist nature of early American immigration law.7

In short, immigration law was ordinary public law for a very long time. This central conclusion raises a new and important question: if the immigration plenary power is not the product of late nineteenth-century cases, and if immigration law was mainstream administrative law during the first decades of the twentieth century, then when was the immigration plenary power doctrine invented? This Article begins to sketch out a possible answer to that question. At the start of the Cold War, in the span of a few short years, immigration cases went from being treated mostly as ordinary administrative law cases to being treated as something very different. The Supreme Court and others suddenly began to recast the Court’s earlier case law in a new exceptionalist light. If we want to tell a story about the immigration plenary power’s invention, then, we should begin by sleuthing for that story in the 1940s and 1950s—not in the 1890s. Yet even once immigration law became ensconced in the rhetoric of exceptionalism, the outcomes of immigration cases continued, for the most part, to track the outcomes one would have expected had the policies at stake not been immigration policies. Indeed, it was not until the Roberts Court came along that the Supreme Court, for the first time ever, deployed the rhetoric of an “immigration plenary power” to resolve constitutional challenges to immigration policies in a manner that departed clearly from the way those challenges would have been resolved outside the immigration context. It thus might be more accurate to say that the immigration plenary power was invented by the Roberts Court, in cases like Hawaii v. Trump and Department of Homeland Security v. Thuraissigiam, than it is to say that it was invented in the waning days of the nineteenth century.8

Debunking our common mythology about the invention of immigration exceptionalism has tremendously important implications for the field. It requires that we rethink the entire constitutional edifice of the discipline, and it offers us new and powerful historical arguments against the modern exceptionalism that is responsible for some of the worst parts of immigration law today.

Unearthing the true origin story of American immigration law also shows the way in which an area of law so marginalized today was so central, in the early twentieth century, to the development of public law. Crack open a casebook on administrative law, and you are most likely to read a story about administrative law’s rise that focuses on commissions regulating railroads, trusts, and financial markets—entities like the Interstate Commerce Commission and the Federal Trade Commission.9 The bureaucracy of immigration regulation and enforcement is typically nowhere to be found. Contrary to this well-worn narrative, however, immigration law was, in the first decades of the twentieth century, an important source of emerging ideas about the judicial oversight of administrative actors. Recovering the role played by immigration law shows that a number of common stories we tell about the development of public law—whether in federal courts, or administrative law, or constitutional law—are incomplete and misleading. Our understanding of public law’s development thus has much to gain from a more accurate account of immigration law’s foundations.10