Reconfiguring Remedial Power in the Post-CASA Landscape: Lower-Court Constraints and the Supreme Court’s Expanding Shadow Docket
Class action lawsuits, which allow a collective group to sue as one, are foundational to understanding the modern American legal system. Before the Federal Rules of Civil Procedure were adopted in 1938, the class-action style of litigation arose through the equitable doctrine of “representative suits.” The seminal case, Smith v. Swormstedt (1853), allowed members of the Methodist Episcopal Church to litigate a dispute on behalf of the entire denomination; the court reasoned that equity could bind absent parties when their interests were identical and adequately represented. That idea, rooted in equity, was later codified in the Federal Rules of Civil Procedure, which recognized that individuals could sue as a collective, and seek collective redress.
In 1966, the Advisory Committee on Civil Rules refined Rule 23 to reflect the constitutional demand for procedural fairness articulated in Hansberry v. Lee (1940). Hansberry held that judgement in a class action cannot be binding for an absent party whose interests were not adequately represented, and thus in violation of the due process clause of the 14th amendment. To address those concerns, the Committee redesigned Rule 23 with a newfound emphasis on the effects of class action proceedings, setting forth procedural matters the court may take to establish fairness and representation. This establishes Rule 23 as a due process safeguard.
Currently, Rule 23 establishes prerequisites for class actions as numerosity, commonality, typicality, and adequacy. It also establishes three types of classes under Rule 23 (b)(1-3): (1) classes are needed to avoid inconsistent or harmful results; or (2) if the defendant acted on grounds that apply to the entire class, such as a single injunction or declaration would resolve the issue for all; or (3) classes are seeking damages where common issues predominate. These requirements underscore that class certification is a formal prerequisite for binding relief, which is essential in ensuring that collective remedies honor constitutional due process.
Comparatively, universal injunctions are orders that apply to all people, regardless of their status as a non-party. Similar to the function of class actions, universal injunctions extend relief beyond the individual plaintiffs, binding the government and their decisions to millions of absent parties who never participated in the lawsuit. So although universal injunctions and class actions are different in form, they both serve as vehicles for securing broad, systemic relief on a group-wide or population-wide basis. However, despite universal injunctions’ de facto function as class-wide relief, they do not have to meet the requirements outlined in Rule 23, which govern class actions, raising concerns over judicial overreach, representational adequacy, and constitutional due process.
Because universal injunctions operate as class-wide relief, they raise the same kinds of representational and due process issues that the Supreme Court addressed in Trump v. CASA Inc.. In that case, argued earlier this year, the Court considered whether a district court can issue a universal injunction that blocks enforcement of a federal executive order beyond the specific parties involved in the lawsuit. The court found that lower courts issuing universal injunctions likely exceed their statutory equitable authority in granting universal relief beyond those named. The majority held a narrow, historically fixed view of the federal courts’ equitable powers and their roots in the English Court of Chancery, reasoning that because the Chancery courts did not typically grant universal relief in 1789, such injunctions exceeded judicial authority. Some legal historians and the dissent emphasize that Chancery practice included “bills of peace,” which provided relief to large groups when joinder was impracticable. However, if equity in 1789 did not permit universal relief, then, in the majority’s view, modern courts lack the authority to issue it now.
Beyond its historical analysis, the majority also grounds its reasoning in the procedural safeguards embedded in Rule 23. Issuing the majority opinion, Justice Barrett writes that “by forging a shortcut to relief that benefits parties and nonparties alike, universal injunctions impermissibly circumvent Rule 23’s procedural protections.” In the majority’s view, universal injunctions issued by lower courts operate as unauthorized classwide relief that bypasses the important due process protections embedded in Rule 23. In a concurring opinion, Justice Kavanaugh urged that plaintiffs may still seek classwide preliminary relief under Rule 23(b)(2), requiring class certification in order to extend the kind of remedial relief universal injunctions had previously offered.
A recent CULR article by Marivi Vergara takes deep issue with the decision in Trump v. CASA Inc. It disputes the majority’s findings that universal injunctions are a relatively recent legal development, citing that the court has long issued injunctive relief that protected large groups of non-parties. The article also aligns with the dissent in arguing that, by limiting universal injunctions, necessary checks on the executive action are also limited to those who can sue. Justice Jackson presents this as an “existential threat to the rule of law,” and writes further that “courts must have the power to order everyone (including the Executive) to follow the law—full stop.” In contrast to the majority’s view that universal injunctions violate the procedural safeguards embedded in Rule 23, the dissent rejects the notion that limiting relief to the few plaintiffs able to sue protects due process. In the dissent’s view, restricting courts to party-specific injunctions leaves the judiciary powerless to prevent constitutional violations, which lays bare a broader constitutional concern of checks and balances.
Placed side by side, the opinions reveal a constitutional paradox at the heart of the CASA decision. The majority insists on stricter standards for classwide relief to protect absent individuals from being bound without adequate representation, a foundational element of due process. However, the dissent insists that those same individuals are left unprotected when the lower courts are prohibited from granting relief on their behalf. To put it more simply, the majority sees the danger as courts doing too much for nonparties, whereas the dissent sees the danger as courts being unable to do anything for nonparties. This raises the question of where to go from here, especially as the Court eliminated universal injunctions for lower courts without finding a practical alternative. However, despite the Supreme Court closing off universal injunctions to lower courts, the Court has continued to issue broad emergency orders without the very safeguards it touts in CASA via the shadow docket.
In the post-CASA legal landscape, Barbara v. Trump (2025) provides a critical test of the suggested remedial framework replacing universal injunctions. In that case, the court successfully certified a nationwide class under Rule 23(b)(2) composed of all children born on or after February 20, 2025, whose parents fell within the categories targeted by Executive Order 14160. The court then granted a preliminary nationwide injunction on behalf of the class, essentially granting remedial relief to non-parties through the class-action vehicle. Some legal commentators have cited this case as a successful test of the class action mechanism for granting broad relief and establishing Rule 23 as the primary path for universal relief.
However, Barbara also exposes the unresolved tension at the heart of CASA. Plaintiffs obtained a nationwide preliminary injunction through a certified Rule 23(b)(2) class within weeks of filing. On its face, the case serves as an effective use of Rule 23 to certify a class, producing a similar effect to that of a universal injunction. However, in practice, the case raises important questions about whether Rule 23’s procedural protections, especially adequacy of representation, can realistically operate as meaningful safeguards under the same urgent timelines that universal injunctions operate under. In acting under these timelines, courts risk converting class certification into a procedural formality rather than the “rigorous analysis” the rule requires. Justice Alito warned precisely of this danger in CASA urging “scrupulous adherence to the rigors of Rule 23,” and argues that “otherwise, the universal injunction will return from the grave under the guise of ‘nationwide class relief.’” Barbara proves his point. While it is nominally adherent to Rule 23, it provides nationwide class relief that mirrors the same, broad systemic relief CASA attempted to minimize. In other words, Barbara simultaneously accomplishes what the majority demanded and illustrates why that demand may be difficult to administer in practice. This begs the question of whether Rule 23 can serve as a viable alternative to universal injunctions.
The fragility revealed in Barbara points to a deeper structural shift that CASA never resolves. Even as the Court insists that broad relief must be in compliance with the disciplined and multilayered safeguards of Rule 23 for the lower courts, its own emergency order practice increasingly falls out of line with those very safeguards. The majority issues a strong case for why district courts must comply with the slower, and more rigorous machinery of class actions, and yet, the Supreme Court itself continues to issue nationwide orders on the shadow docket that act as de facto class actions without the same compliance it demands of the lower courts. As a result, CASA constrains lower-court power even as shadow docket emergency orders consolidate remedial authority in the hands of the Supreme Court.
The Court’s order in Noem v. Perdomo illustrates this dynamic with particular clarity. In that case, Judge Frimpong of the Central District of California granted a temporary restraining order to prevent federal agents from stopping and arresting people based on any one or combination of their appearance, language they speak, and where they live and work. Upon further government challenge, the Ninth Circuit heard the case and applied the Nken four-factor framework, ultimately denying the stay application citing in the opinion that “plaintiffs were likely to succeed in proving their factual allegations regarding defendants’ stop and arrest practices.” However, once heard on the shadow docket, the Supreme Court granted an emergency stay that overturned the district court’s injunction, immediately reinstating the federal immigration policy nationwide, producing the kind of sweeping, nationwide effect that CASA sought to eliminate. None of the individuals affected by the Noem decision had the opportunity to be parties to the case, much less receive the kind of adequate representation Rule 23 would require, highlighting the irony of the CASA decision in limiting lower courts’ authority to grant broad relief, even as the Court continues to issue sweeping directives that reach far beyond the named parties. The Noem decision underscores how after CASA, the authority to issue broad, nationwide remedies has migrated upward to the Supreme Court, even as the Court has withdrawn that same authority from lower courts. This tension complicates the narrative that CASA reduces judicial power, and instead suggests that the Court has consolidated its authority at the highest level by eliminating universal injunctions while maintaining a path for emergency orders to bypass percolation in lower courts, full reviews, and reasoned opinions.
By stripping lower courts of the ability to issue universal injunctions and demanding rigorous adherence to Rule 23, the Court appears to attempt to limit the judiciary’s institutional reach. However, the Court has become increasingly reliant on the shadow docket’s emergency orders which often mirror the very breadth and immediacy that CASA eliminated for lower courts, but without the same procedural safeguards they demand of lower courts. This tension is especially concerning given the unprecedented number of emergency applications filed by the Trump administration and the Court’s willingness to grant them. In the first six months of President Trump’s second term, his administration filed more than double the amount of requests for emergency relief as the George W. Bush and Obama administrations did in 16 years. More importantly, the Supreme Court has granted 83% of the administration's requests on the shadow docket. These patterns have led critics to argue that the Court is aligned with the Trump administration, especially on the shadow docket.
The Court has simultaneously limited lower courts’ ability to act as a meaningful check on executive power while consolidating judiciary power at the highest level, emboldening the Court’s ability to impose nationwide outcomes through emergency orders. What emerges in the post-CASA legal landscape is not a doctrine of remedial restraint, but rather a doctrine of consolidation with the Court positioning itself as willing and able to carry out sweeping nationwide outcomes in alignment with the current administration.