Introduction
Can prisoners litigate habeas corpus cases as class actions? This anodyne procedural question is an emergent civil rights dispute.1 Facing the Trump Administration’s aggressive attempts to remove noncitizens under a wartime emergency statute,2 the Supreme Court directed that noncitizens must use habeas proceedings to challenge their removal.3 At roughly the same time, the Court disapproved of “universal injunctions” against unlawful government action, largely barring district courts from extending injunctive relief beyond what is necessary to protect party plaintiffs.4
For many noncitizens facing removal — most of whom have no practical ability to mount individual habeas challenges — the only workable protection is a habeas class action.5 Understanding the stakes, district courts around the country have begun to certify habeas classes.6 But, even as the Court has extinguished other anti-removal remedies, two Justices now argue that courts cannot certify habeas classes.7 Justice Alito (joined by Justice Thomas) declared habeas class treatment to be “highly questionable,” even “doubtful.”8 It is the now-urgent question of habeas class treatment that we explore here, and examples of Trump-era removal litigation enrich our discussion throughout.
Our conclusion is straightforward: Considering the pertinent statutes and rules, as well as the underlying purposes of representative litigation, courts should be able to certify habeas classes that present common legal questions. Idiosyncratic habeas law might sometimes mean that people with related habeas claims lack commonality sufficient for class treatment, but class actions are appropriate when enough commonality exists. The idea that habeas litigants cannot proceed as a class contravenes basic premises of the federal habeas corpus statute and the Federal Rules of Civil Procedure (FRCP).
We proceed in three Parts. Part I provides background, explaining how habeas class treatment became a flashpoint in one of this era’s great civil rights struggles. Although the Supreme Court has formally reserved the question of whether habeas cases are eligible for class-wide adjudication,9 the rest of the judiciary has a long history of habeas class certification.10 Overstating the degree of lower court consensus is difficult: The six regional circuits to have formally reached the question all endorse habeas class treatment, and the remaining circuits embrace it in practice. It is only recent, auxiliary Supreme Court opinions, and those opinions alone, that form any basis for the legal “doubt[]” to which Justice Alito alluded.
In Part II, we explain and advocate the approach that courts have always used to decide what procedure applies in habeas cases: a conflict-of-laws analysis that looks to whether a generally applicable procedure is historically and practically compatible with habeas adjudication. Al-though habeas corpus proceedings are considered “civil” in a general sense, they are specialized proceedings not subject to all of the procedural rules that govern ordinary civil actions.11 And Rule 81 of the FRCP sets forth the conflicts framework for deciding which procedures apply in habeas cases.12
Under Rule 81, and unless some specific statute (or bespoke habeas rule for postconviction cases) directs otherwise, courts must apply the FRCP to which habeas practice has historically “conformed.”13 If a particular rule (or some provision of it) does not “conform[],” however, then courts may still apply that rule’s content “by analogy,” under other statutory authority.14 When courts have deemed the class action rule (Rule 23 of the FRCP) to be nonconforming and therefore inapplicable of its own force, they have long applied its content analogically and by force of either the All Writs Act15 (AWA) or a remedial provision of the federal habeas statute.16 Justice Alito has simply mistaken Rule 81 as a restriction on when class actions are permitted, rather than as a rule about when they are required.17
In Part III, we establish crucial propositions favoring representative habeas litigation featuring shared challenges to common aspects of broad detention policies. Habeas class treatment is often desirable because it promotes efficiency and distributive fairness.18 It also fits comfortably within the tradition and basic purposes of Rule 23(b)(2), which, since 1966, has governed representative litigation seeking injunctive and declaratory relief.19 A Rule 23(b)(2) class action is appropriate when a single order can provide indivisible relief on a legal issue shared across a plaintiff class,20 such as when a group of noncitizens brings identical legal challenges to the same removal policy.21
Our purpose is not to urge an outcome in a specific piece of litigation, although our conclusions have obvious real-world implications. Instead, and in the spirit of academic inquiry, we offer thorough histories of habeas class adjudication and the conflict-of-laws approach used to specify habeas procedure. Those histories capture a clear framework for deciding when representative adjudication is lawful in habeas cases. Candidly, we were surprised by the one-sidedness of lower court class action history. With only very minor caveats, every court to have considered the question has determined that habeas cases are eligible for class action treatment.22
Considering this pattern alongside the animating purposes of Rule 23(b)(2), we can find no serious argument that Rule 81 — or anything else — excludes habeas class treatment. Class action adjudication remains appropriate when habeas challenges raise common questions and when the ordinary rules for class actions are otherwise satisfied. Those conditions won’t always exist; postconviction challenges, in particular, will often turn on individual procedural or substantive issues not suited to class treatment.23 But habeas class actions can be an important tool in disputes over things like immigration and pretrial custody, where large groups of detainees challenge the legality of detention policies across the board.24