Trump v. CASA. In 2025, the Supreme Court further limited the possibility of injunctive relief by restricting the availability of what are sometimes called nationwide or universal injunctions. Specifically, as Mila Sohoni explained, it “held that federal courts may not give universal injunctions, which are orders that block the application of a law or an executive branch action to anyone who might be harmed by it, not just its application to the plaintiffs.” On its face, that’s a pretty dramatic restriction, which might allow significant and obvious unconstitutional conduct to proceed unchecked. At the same time, however, the CASA court “described several mechanisms that might lead to comparably broad injunctive relief, including class actions.”