Class actions expected to surge following Supreme Court injunction ruling

District courts in California, as well as the rest of the country, will be flooded with class actions now that the U.S. Supreme Court has limited lower court judges' ability to grant nationwide injunctions in lawsuits to block presidents' policies and executive orders, some legal experts said.

"No question," Michael T. Morley, a professor at Florida State University College of Law, said in a phone interview on Friday's decision.

Erwin Chemerinsky, dean of UC Berkeley School of Law, agreed in an email, saying the ruling "will lead to a wave of such suits in the instances where nationwide injunctions previously had been issued."

What's less certain is how the court's 6-3 ruling will affect the underlying case involving President Donald Trump's executive order barring birthright citizenship - which was struck down by three district judges in nationwide injunctions - as well as other preliminary injunctions in cases against the president that affect people and organizations who did not sue on their own behalf.

"The Government's applications to partially stay the preliminary injunctions are granted, but only to the extent that the injunctions are broader than necessary to provide complete relief to each plaintiff with standing to sue," Justice Amy Coney Barrett - a Trump appointee - wrote for the majority.

"The lower courts shall move expeditiously to ensure that, with respect to each plaintiff, the injunctions comport with this rule and otherwise comply with principles of equity," she added. Trump et al. v. CASA Inc. et al., 2025 DJDAR 5795 (S. Ct., filed March 13, 2025).

Barrett's opinion does not address the underlying dispute in the case of whether Trump's birthright citizenship executive order is constitutional and postponed it for 30 days. She also did not address more than two dozen other preliminary injunctions by judges across the country blocking Trump's orders or policies.

That will leave plenty of work for the lower courts to determine whether giving relief to the plaintiffs may require a judge to grant universal relief anyway.

"Whether that is the case for these plaintiffs is now up to the lower courts to decide," Mila Sohoni, a professor at Stanford Law School, wrote in an email. "The Supreme Court did not itself actually narrow the injunctions; after announcing the complete relief principle, it left the work of reconsidering the injunctions' scope to the lower courts."

The district court judges - including Senior U.S. District Judge John C. Coughenour of the Western District of Washington - cited an 1898 U.S. Supreme Court decision that ruled that a child of Chinese immigrants born in San Francisco was a U.S. citizen because he was born in the United States, citing the citizenship clause of the 14th Amendment. U.S. v. Wong Kim Ark, 169 U.S. 649 (1898).

But Barrett, citing the Judiciary Act of 1789 - which she said didn't include the ability of a district judge to grant a universal injunction against a president's orders - ruled that such injunctions likely exceed the equitable authority given to the federal judiciary.

"Nothing like a universal injunction was available at the founding, or for that matter, for more than a century thereafter," Barrett wrote.

"No one disputes that the Executive has a duty to follow the law," she added. "But the Judiciary does not have unbridled authority to enforce this obligation -- in fact, sometimes the law prohibits the Judiciary from doing so."

Barrett agreed with U.S. Solicitor General D. John Sauer, who portrayed nationwide injunctions largely as a 21st century phenomenon that were used in legal challenges to policies instituted by Presidents George W. Bush, Barack Obama, Joe Biden, and Trump.

Samuel L. Bray, a professor at the University of Notre Dame Law School who was cited by Barrett several times, said in an email: "Some of the existing universal injunctions will be narrowed by the district courts that gave them, and others will be narrowed by courts of appeals."

Friday's ruling could affect many other cases. Senior U.S. District Judge Susan Y. Illston of San Francisco, an appointee of President Bill Clinton, blocked Trump from ordering large-scale government employee firings and layoffs without congressional approval. A divided 9th U.S. Circuit Court of Appeals panel denied the government's motion for a stay pending appeal.

Sauer sought relief from the U.S. Supreme Court, where the case between federal employee unions and the Trump administration is pending. Trump et al. v. American Federation of Government Employees, AFL-CIO et al., 24A1174 (S. Ct., filed June 2, 2025).

In the birthright citizenship case, Attorney General Rob Bonta said in an emailed statement: "The Supreme Court's decision allows the lower courts to further consider the scope of the district court's nationwide injunction -- which we believe is clearly necessary to provide full relief to the states. We remain hopeful that the courts will see that a patchwork of injunctions is unworkable, creating administrative chaos for California and others and harm to countless families across our country."

Trump, during a news conference, hailed the decision. "We can now promptly file to proceed with numerous policies that have been wrongly enjoined on a nationwide basis," he said.

David A. Carrillo, executive director of Berkeley Law's California Constitution Center, said the ruling could create perverse incentives for the government, allowing the president to violate the Constitution but avoid judicial review. "This is another example of the court using its history-and-tradition [standard] to apply a narrow view, in this instance of the federal judiciary's power," he wrote.

He also said states may have difficulty establishing standing, a view shared by Morley, who also said associational and organizational standing may also be tough to get past some judges.

"These types of cases will be harder to bring," Morley said.

Barrett's ruling was accompanied by three concurrences from judges appointed by Republican presidents as well as two dissents from Democratic appointees.

Justice Clarence Thomas, an appointee of President George H.W. Bush, wrote that lower courts "should carefully heed this Court's guidance and cabin their grants of injunctive relief in light of historical equitable limits. If they cannot do so, this Court will continue to be 'dutybound' to intervene."

Justice Samuel A. Alito Jr., an appointee of President George W. Bush, fretted that the practical impact of the decision might be undermined if lower court judges allow states to sue on behalf of their citizens or if limits on class certification are not strictly enforced.

"Lax enforcement of the requirements for third-party standing and class certification would create a potentially significant loophole to today's decision," he wrote. "Federal courts should thus be vigilant against such potential abuses of these tools."

Justice Sonia M. Sotomayor, an Obama appointee, blasted the decision, saying it "asks this Court to hold that, no matter how illegal a law or policy, courts can never simply tell the Executive to stop enforcing it against anyone."

"The gamesmanship in this request is apparent and the Government makes no attempt to hide it," she wrote. "Yet, shamefully, this Court plays along."

A 9th Circuit panel heard arguments on the Trump administration's appeal of Coughenour's preliminary injunction in the birthright citizenship case on June 4. Two days later, the panel vacated submission of the case until Friday's Supreme Court ruling. State of Washington et al. v. Trump et al., 25-807 (9th Circ., filed Feb. 7, 2025).