Trump v. CASA: How the Limit on Universal Injunctions Changed Immigration Litigation

On June 27, 2025, the Supreme Court held that federal courts likely lack authority to issue "universal" injunctions. The decision did not end nationwide challenges to immigration policies, but it changed how they are brought: through class actions, suits by organizations and states, and requests to vacate agency rules.

What the Court decided

The CASA case arose from Executive Order 14160, signed on January 20, 2025, which sought to deny citizenship to certain children born in the United States. Three district courts blocked the order with "universal" injunctions, meaning injunctions that barred the government from applying the order to anyone, not just to the plaintiffs. The government asked the Supreme Court to narrow those injunctions.

The Court, in an opinion by Justice Barrett, held that universal injunctions likely exceed the equitable authority that Congress granted federal courts in the Judiciary Act of 1789. It granted partial stays so that the injunctions would be no broader than necessary to provide complete relief to each plaintiff with standing to sue. Importantly, the applications did not ask the Court to decide whether the executive order was lawful, and the Court did not address that question. Readers interested in how judicial remedies work generally may find useful background in our explainer on the role of injunctions in legal disputes.

What the decision left open

CASA limited one remedy but left others in place. Three routes have dominated immigration litigation since then:

• Class actions. Under Rule 23 of the Federal Rules of Civil Procedure, a court can certify a class of people who share common legal claims and grant relief to the whole class. In the birthright citizenship litigation itself, a district court in New Hampshire provisionally certified a nationwide class of affected children after CASA, and that case, Trump v. Barbara, reached the Supreme Court on the merits.
• Vacatur under the APA. The Administrative Procedure Act allows a court to "hold unlawful and set aside" agency action (5 U.S.C. § 706(2)). Many courts treat setting aside a rule or policy as different from an injunction, so it can have broad practical effect. Several 2026 immigration decisions, including the ruling against USCIS's nationality-based holds discussed in our Dorcas v. USCIS article, relied on vacatur.
• Suits by states and organizations. When the plaintiff is a state or a membership organization, "complete relief" may cover more people than a single individual's case would.

Why class actions matter for delayed applications

Class actions are not new in the immigration delay context. Applicants who share the same problem, such as a category of petitions that USCIS has stopped processing, sometimes join together so that one court decision binds the agency for everyone in the class. An example from the child-citizenship field is this overview of a class action challenging N-600K processing delays. A related theory for spouses of U.S. citizens is discussed in this analysis of a possible K-3 mandamus class action.

Class litigation has trade-offs. Certification can take months, the class definition may not fit every person's facts, and a class member generally cannot pursue the same claim separately. For some applicants, an individual lawsuit for unreasonable delay remains faster. Our article on judicial discretion in federal courts explains why outcomes can vary from one court to another.

Practical takeaways

• If a court blocks an immigration policy, check whether the order protects only named plaintiffs, a certified class, members of an organization, or everyone through vacatur.
• Membership in an organization that is a plaintiff can matter. Keep proof of membership dates if you rely on it.
• Do not miss your own deadlines while waiting for a class decision; class status rarely extends individual filing deadlines automatically.
• Follow later rulings. The constitutional question left open in CASA was decided in Trump v. Barbara on June 30, 2026.

For a broader view of how recent federal decisions affect pending files, see what recent federal court rulings mean for pending immigration cases.

How a class gets certified

A class action is not automatic. Under Rule 23(a), the plaintiffs must show that the class is so numerous that joining everyone is impracticable, that there are common questions of law or fact, that the named plaintiffs' claims are typical of the class, and that they and their lawyers will adequately represent it. Immigration class actions usually seek certification under Rule 23(b)(2), which covers cases in which the government has acted on grounds that apply generally to the class, so that a single injunction or declaration is appropriate for everyone. Courts can also certify a class provisionally while deciding a request for preliminary relief, as happened in the birthright citizenship litigation.

Frequently Asked Questions

Did Trump v. CASA decide that the birthright citizenship order was valid?

No. The Court expressly did not decide that question. It addressed only the scope of the injunctions. The Supreme Court later held the order unconstitutional in Trump v. Barbara (June 30, 2026).

Can a court still block an immigration policy nationwide?

Courts can still provide broad relief through certified class actions and, according to many courts, by vacating unlawful agency action under the APA. A universal injunction in favor of non-parties is what CASA restricted.

Should I join a class action or file my own case?

It depends on your facts, timing and the class definition. An immigration lawyer can compare both routes for your situation.