abstract. Third-party standing is relevant to a wide range of constitutional and statutory cases. The Supreme Court has said that, to assert such standing, a litigant must ordinarily have a close relationship with the right holder and the right holder must face obstacles to suing on their own behalf. Yet the Court does not seem to apply that test consistently, and commentators have long critiqued the third-party standing doctrine as incoherent. This Article argues that much of the doctrine’s perceived incoherence stems from the Supreme Court’s attempt to capture, in a single principle, disparate scenarios raising distinct problems of both theory and practice. The Article “unpacks” third-party standing in two respects. First, it identifies true third-party standing problems by distinguishing them from first-party claims, largely by reference to the “zone-of-interests” concept. If litigants fall within the zone of interests of the substantive right they wish to invoke and they have an injury in fact, they may establish first-party standing based on their own rights. If they do not fall within the zone of interests, then they must rely on the rights of third parties. Second, the Article distinguishes among three types of parties invoking third-party standing: directly regulated parties, collaterally injured parties, and representative parties. The results in the Court’s third-party standing cases tend to track these distinctions, and we argue that it is time for the Court to recognize them in doctrine. The Article also rejects prior efforts by scholars to posit a general “valid rule” requirement as a way of reconciling the cases, an approach that we contend is both under and overinclusive. The Article concludes by highlighting aspects of modern litigation practice that may need revision in light of the unpacked third-party standing doctrine.

authors. Curtis A. Bradley is Professor, University of Chicago Law School. Ernest A. Young is Alston & Bird Professor, Duke Law School. For helpful comments and suggestions, we thank Matt Adler, Joseph Blocher, Erin Blondel, Kathy Bradley, Brannon Denning, Richard Fallon, Amanda Frost, Tara Grove, Aziz Huq, Maggie Lemos, Henry Monaghan, Jim Pfander, Richard Re, Neil Siegel, Richard Stewart, and participants in a Duke Law School faculty workshop. For excellent research assistance, we thank Michelle Lou.

Introduction

The Supreme Court has said that third-party standing is generally not allowed. A litigant normally “must assert his own legal rights and interests, and cannot rest his claim to relief on the legal rights or interests of third parties.”1 But this rule seems to be honored in the breach. The Court has described the third-party standing doctrine as a “prudential” limitation that can be overcome based on various considerations,2 and has on many occasions allowed such standing. The Court has said that litigants invoking third-party rights must have a close relationship to the right holders, and that the right holders must face obstacles to suing on their own behalf.3 But the Court often fails to apply this “relationship-plus-obstacle” test. It has not done so, for example, in some cases involving vendors of goods and services who assert violations of their customers’ rights.4 To make matters more uncertain, the Court has in recent years questioned the very idea of prudential standing limits.5 Unsurprisingly, commentators have long doubted the coherence, and even lawfulness, of the third-party standing doctrine.6

Controversy over third-party standing doctrine intensified in 2020 in connection with the June Medical Services case before the Supreme Court.7 In that case, abortion doctors in Louisiana challenged a state law requiring them to have admitting privileges at a nearby hospital. Louisiana argued that the doctors lacked third-party standing to raise the abortion rights of their clients.8 A majority of the Court upheld the doctors’ third-party standing, but its decision did nothing to clarify the doctrine.9 There was no majority opinion on the issue. A plurality relied, in part, on Louisiana’s failure to raise the standing argument until it reached the Supreme Court, and did not explain how the traditional relationship-plus-obstacle test was satisfied.10 Several Justices dissented on the standing issue.11

Despite their disagreements, all the Justices who addressed the issue in June Medical Services wrote as if a unitary doctrine governed third-party standing. The plurality acknowledged a “rule” against third-party standing, but said that this rule was “hardly absolute.”12 Similarly, Justice Thomas’s dissent referred (critically) to “our prudential third-party standing doctrine,”13 and Justice Alito’s dissent invoked “our established test for third-party standing.”14

In this Article, we argue that much of the third-party standing doctrine’s incoherence stems from the attempt to capture, in a single principle, disparate scenarios raising distinct problems of both theory and practice. The third-party standing doctrine needs to be unpacked. We do not maintain that this will solve all of its problems. But unpacking the general question will resolve many issues and provide a more helpful frame to understand those that remain. Our approach also suggests that third-party standing problems may lurk in areas not previously considered to be within the doctrine’s scope.

We propose to unpack the doctrine in two respects. First, we identify true third-party standing problems by distinguishing them from first-party claims. True third-party standing problems arise only if the underlying law confers no right on the litigant wishing to invoke it. There seems to be general agreement on this point, but neither courts nor scholars have identified with precision the nature of the right required for standing. We argue—reviving an insight that Professor Tribe offered decades ago15—that the answer lies with the familiar “zone-of-interests” test. If litigants fall within the zone of interests of the substantive right they invoke and they have an injury in fact, they may rely on their own first-party rights for standing. If they fall outside the zone of interests, they must rely on the rights of third parties. That move, we suggest, helps resolve ambiguities across standing doctrine in both constitutional and statutory cases.

By relying on the zone-of-interests concept to distinguish first- and third-party claims, we reject two prominent alternative approaches. One is the leading suggestion in the literature, often echoed in judicial dictum, that parties lack first-party rights unless they have a “cause of action” to enforce those rights.16 But as we explain, standing doctrine frequently asks who may assert a right in contexts in which no cause of action is necessary. It makes little sense, for example, to demand that a party establish an affirmative cause of action in order to assert a right or claim as a defense to someone else’s lawsuit.

We also reject an argument, which has been made by a number of leading scholars and endorsed by others, that inconsistencies in the case law can be reconciled by positing a general right not to be subject to an invalid rule.17 While we accept that some constitutional provisions provide universal rights against enforcement of rules that are invalid in certain ways, we reject the valid rule hypothesis as an account of third-party standing. This hypothesis, we argue, is both under and overinclusive as an account of third-party standing doctrine and inconsistent with the Supreme Court’s effort in modern standing decisions to reconcile public and private models of adjudication.

The second element of our approach unpacks true third-party standing problems by distinguishing three classes of litigants:

1. Directly Regulated Parties: The litigant is directly regulated by the challenged law or conduct, but invokes rights held by others as the basis of their challenge. The doctors in June Medical Services fell into this category because they were regulated by the abortion law, but challenged it on the basis of their patients’ right to choose.18

2. Collaterally Injured Parties: The litigant is not the regulated entity, but the challenged law or conduct causes the litigant injury in fact. The litigant challenges the law or conduct on the ground that it violates rights held by others. Criminal defense lawyers challenging a state court’s refusal to appoint counsel for indigent defendants furnish an example.19

3. Representative Parties: The litigant is a representative party who may or may not have an injury in fact of their own, but seeks to redress injuries to others as well. Many established mechanisms allow one party to stand in for others who cannot litigate their own claims or are too numerous to litigate them efficiently. Parents seeking to sue as “next friends” of their children fall into this category,20 as do class actions and other forms of representative and aggregate litigation.

The results in the Supreme Court’s third-party standing cases tend to track these distinctions, but the Court’s explanations rarely acknowledge them. Unpacking these categories focuses attention on the questions peculiar to each, the implications of which have yet to be fully considered by either courts or scholars. Our goal is to identify more explicitly the tendencies in the case law, suggest some friendly amendments, and consider how some of the problems lurking just beneath the surface should be addressed. This unpacking, we contend, yields not only greater doctrinal coherence, but also a better alignment of standing doctrine with the constitutional and prudential functions that the doctrine is intended to serve.21

Third-party standing is relevant to a wide range of constitutional litigation. It arises, for example, when providers of goods or services seek to raise the rights of their customers or clients—for example, in claims by sellers of beer and firearms,22 doctors prescribing contraceptives,23 criminal defense lawyers,24 and homeowners seeking to sell to African American purchasers in violation of a restrictive covenant.25 Similar issues also lurk on the structural side of constitutional law. They emerge when individuals subject to government action invoke the separation-of-powers prerogatives of particular government institutions—such as the President’s removal authority26 or limitations on legislative vetoes27—or when particular persons or entities seek to represent the interests of government institutions.28 Third-party issues likewise appear in federalism cases when individuals invoke limits on Congress’s enumerated
authority29 or states assert the rights of their citizens.30

Prior scholarship on third-party standing has focused on constitutional litigation. We suggest, however, that scholars should also pay attention to statutory claims, which raise third-party standing issues of their own. Our third category of third-party problems (involving representative parties) demonstrates, moreover, that important aspects of modern federal procedure, such as class actions, multidistrict litigation (MDLs), and nationwide injunctions, can usefully be seen as raising third-party standing issues.31 These issues of representation and remedial scope have not generally been part of the conversation about third-party standing, but they should be—and some aspects of representative and aggregate litigation should be reconsidered in light of general concerns about third-party standing.

Part I of this Article traces the relevant doctrines and their history—in particular, the clash between “private-rights” and “public-law” models of adjudication. We also address whether the third-party standing rule is best viewed as constitutional or prudential in nature. Part II establishes the outer bounds of the third-party problem by distinguishing those cases that actually involve first-party claims. Once we have identified true third-party problems, Part III unpacks them into three distinct categories. We show that the Supreme Court’s decisions have, in fact, generally distinguished among these categories of cases, although they have not always done so very clearly. The doctrine would work better and be easier to justify theoretically if the Court made these distinctions explicit. Unpacking the doctrine into these categories, moreover, reveals aspects of the doctrine in need of reform, especially with respect to cases involving representative parties.