Last Month at the Supreme Court | May 2025

As Washington continues to buzz with activity, we are keen to report the latest developments in the May 2025 edition of Last Month at the Supreme Court. Learn about the Court’s evaluation of consequential issues, including whether a single district court’s injunction can extend to affect individuals and interests not before that court following President Trump’s executive order restricting birthright citizenship.

Other compelling questions before the Supreme Court this month include:

• The proper procedure for filing a notice of appeal after the ordinary deadline has passed but before a district court formally reopens the appeal period
• Whether gas entities challenging waivers, which might eventually require automakers to hit certain zero-emission vehicle targets, can establish a concrete injury for Article III standing
• A federal court’s power to certify a class action where some members of the proposed class lack Article III injury

These cases highlight the Court’s continued focus on the separation of powers, legal precedent, and constitutional interpretation. Take a minute to read or listen to our brief summaries to gain insight into how these key developments may impact your business or organization. For more information, please contact  Chantel Febus, James Azadian, Mark Magyar, Kyle Asher, Christopher Sakauye, Monika Harris, or Ryan VanOver.

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Supreme Court Considers Standing to Challenge Clean Air Act Waiver Based on Market Impact 

The Supreme Court recently heard oral argument in Diamond Alternative Energy, LLC v. Environmental Protection Agency (No. 24-7), a case examining whether economic harm stemming from market forces influenced by environmental regulation can support Article III standing. At issue is California’s authority to enforce its own emission standards, through a waiver granted by the U.S. Environmental Protection Agency (EPA) under Section 209 of the Clean Air Act (CAA). Read the full synopsis here.

Decision Alert: Supreme Court Clarifies Medicare DSH Reimbursement—Key Implications for Hospitals in Advocate Christ Medical Center v. Kennedy

On April 29, in a 7-2 decision authored by Justice Barrett, the Supreme Court held in Advocate Christ Medical Center v. Kennedy (No. 23-715) that the “Medicare fraction” of the Medicare program includes only those patients who were eligible to receive supplementary social income (SSI) payments during the month of their hospitalization, as opposed to patients who were merely enrolled in the SSI system at the time of their hospitalization. Read the full synopsis here.

Supreme Court Weighs Certification of a Class Including Uninjured Plaintiffs

In Laboratory Corporation of America Holdings v. Davis (No. 24-304), the Supreme Court has the opportunity to decide whether a federal court may certify a class action under Federal Rule of Civil Procedure 23(b)(3) when some members of the proposed class lack any Article III injury. If the Court reaches the question presented, its ruling has the potential to send shockwaves through the high-stakes world of class action litigation, where defendants are often pressured to settle claims regardless of their merit when faced with potentially catastrophic damages awards. But a gleaming procedural infirmity appears likely to prevent the Court from doing so. Read the full synopsis here.

Supreme Court Weighs Procedure for Reopened Federal Appeals 

The Supreme Court is currently considering a procedural question that could significantly affect how appeals are handled when litigants miss filing deadlines due to delayed notice of judgment. In Parrish v. United States (No. 24-275), the Justices will decide whether a litigant who timely files a notice of appeal after the ordinary deadline—but before a district court formally reopens the appeal period—must later file a second, duplicative notice once the period is officially reopened. Read the full synopsis here.

Supreme Court Hears Argument on Nationwide Scope of Injunction 

On May 15, 2025, the Supreme Court heard oral argument on three related emergency applications—Trump v. CASA, Inc.(No. 24A884); Trump v. Washington (No. 24A885); and Trump v. New Jersey (No. 24A886)—arising from President Trump’s January 20, 2025, executive order restricting birthright citizenship. As Dykema previously reported, the case raises a critical legal question: whether a federal district court may issue nationwide, or “universal,” injunctions and, if so, under what legal framework such relief is justified. Read the full synopsis here.