Supreme Court Substantially Limits Universal Injunctions (Trump v. CASA): Implications for Litigation Against the Government

In Trump v. CASA, the U.S. Supreme Court has ruled that federal courts may no longer issue injunctions on a nationwide basis except where necessary to protect the plaintiffs before them. The decision is expected to significantly reshape constitutional and regulatory litigation in the United States by limiting injunctive relief to the parties before the court. This promises to increase the importance of class actions and associational suits, and may potentially shift some challenges to state courts. It may also reduce the government’s incentives to seek appellate review, which could lead to greater legal fragmentation across jurisdictions. Even when a policy is vacated under the Administrative Procedure Act (APA), it is possible that agencies will seek to reimplement it through adjudications or guidance, requiring new litigation to stop its continued enforcement. The ruling applies equally in federal court suits against federal or state governments, and is likely to influence forum selection and litigation strategy moving forward.

In this article, Sidley partner David Carpenter and associate Christopher Healy analyze the U.S. Supreme Court’s decision in Trump v. CASA, which significantly limits the use of universal or nationwide injunctions by federal courts. They explain the Court’s reasoning, highlight the unresolved questions around the APA and Article III, and discuss the practical implications for those pursuing or defending legal actions, including increased fragmentation in regulatory enforcement, reduced reliance on others’ legal victories, and a greater strategic emphasis on class actions, associational standing, and potential relief in state courts.