This month, the Supreme Court is considering two major challenges to Trump overreach—one on its merits docket and one on its shadow docket—and CAC has been involved in both.

At the beginning of November, the Supreme Court heard oral argument in the challenge to President Trump’s unlawful tariffs. Our amicus brief ex

plained that President Trump doesn’t have authority under the International Emergency Economic Powers Act (IEEPA) to single-handedly set global tariffs. As CAC Legal Fellow Simon Chin explained after oral argument, “The Government argues that when Congress passed IEEPA, in 1977, it carried forward authority over tariffs from an older law called the Trading with the Enemy Act (TWEA). But as Neal Katyal, counsel for the private challengers, emphasized at oral argument when citing our brief, a 1933 amendment to TWEA severed that law from its original war powers foundations.”

The stakes of this case are high, as CAC President Elizabeth Wydra emphasized in an interview with the Canadian Broadcasting Corporation. As Elizabeth explained, the Court has “so far, in this second Trump administration been very much acquiescent in Trump’s power grabs. This will be a test of whether they will actually be the check that the Constitution envisions on the Executive.”

Among Trump’s many other disturbing power grabs has been his deployment of the National Guard in American cities. CAC is fighting back in courts from coast to coast, filing amicus briefs against Trump’s unlawful use of the National Guard in Chicago, Los Angeles, and Washington D.C.

Most recently, CAC filed a brief in the Supreme Court explaining why it should deny the government’s request to stay a district court injunction blocking the deployment of the National Guard in Chicago. Our brief explains that Martin v. Mott, a case arising out of the War of 1812, doesn’t insulate the President’s deployment decision from judicial review.

Because the Trump administration relies on Mott in claiming that courts can’t review its decision to deploy the Guard, CAC’s historical research has been a helpful resource in setting the record straight. Our brief was cited as providing a valuable perspective in Slate magazine and the One First newsletter. And when Stephen Miller, the architect of Trump’s immigration agenda, seemingly claimed that Trump had unreviewable “plenary power,” CAC’s Deputy Chief Counsel Brian Frazelle was quick to explain that he was “flat wrong.”

With both the Los Angeles National guard case and the consolidated tariffs cases before the Supreme Court, CAC’s historical research provides key context and insight for the Justices. As Elizabeth suggested, now is the Supreme Court’s chance to show it can serve as a check on the Trump administration’s lawless actions.

• Appalachian Voices v. Environmental Protection Agency — The D.C. Circuit is considering whether the Trump administration can unilaterally terminate an entire mandatory grant program created by Congress. Our brief argues that the Constitution’s separation of powers prohibits the President from unilaterally withholding federal funds based on disagreement with congressional policy, and because the Trump administration unilaterally terminated a mandatory grant program, the executive branch violated the Constitution’s separation of powers. C. Circuit Court of Appeals, brief filed November 3.
• League of United Latin American Citizens v. Executive Office of the President — WIN — The D.C. District Court held that President Trump’s executive order requiring proof of citizenship on the Federal Form for registering voters violated the separation of powers. Echoing our brief, the court observed that the Elections Clause “provides that Congress—not the President—is the check on States’ authority to regulate federal elections.” C. District Court, decision rendered October 31.
• Learning Resources v. Trump and Trump v. V.O.S. Selections — The Supreme Court is considering whether President Trump has the legal authority to single-handedly impose tariffs. Our brief responds to a historical argument made in support of the tariffs—namely, that the relevant federal law incorporates a traditional presidential authority to impose tariffs during wartime that traces back to the nineteenth century and was first codified in the Trading with the Enemy Act of 1917 (TWEA)—explaining why this narrative is unsound at every step.  Supreme Court, brief filed October 24.
• Illinois v. Trump— WIN — In October 2025, the Seventh Circuit denied the administration’s motion for a stay, leaving in place a district court order that prevents troops from deploying in Chicago. In doing so, the Seventh Circuit adopted the reasoning of CAC’s amicus brief to conclude that Martin v. Mott does not foreclose judicial review. The Trump administration subsequently asked the Supreme Court to stay the district court’s order, and CAC filed an amicus brief opposing the administration’s application, reiterating our arguments about why courts can review the President’s decisions to mobilize the National Guard. That application is currently pending. Seventh Circuit, brief filed October 12, decision rendered October 16, brief filed in Supreme Court October 20.
• Community Legal Services in East Palo Alto v. HHS — WIN — In a case challenging the Trump administration’s unlawful decision to cut off funding for legal services for unaccompanied children in immigration proceedings, the Ninth Circuit denied the government’s petition for rehearing en banc. The Court addressed—and rejected—the government’s jurisdictional argument. Echoing our brief, the Court understood the Plaintiffs to challenge the government’s failure to comply with the TVPRA’s mandate, rather than raise a breach-of-contract claim. Ninth Circuit, decision rendered October 10.
• Grundmann v. Trump — The D.C. Circuit is considering whether Donald Trump’s attempted firing of the Chair of the Federal Labor Relations Authority was illegal. Our brief explains why long-established practice has placed the validity of multimember independent agencies like the FLRA beyond doubt, and also demonstrates that the text and history of the Constitution further underscore the legitimacy of multimember independent agencies. C. Circuit, brief filed October 10.

• November 5: CAC President Elizabeth Wydra joined Canadian Broadcasting Corporation to discuss Learning Resources v. Trump. “What’s at stake for Trump with Supreme Court tariff case?”
• November 4: CAC’s brief was cited in an article from SCOTUS Blog discussing the amicus briefs filed in Learning Resources v. Trump. “The other arguments in Trump’s tariffs case”
• November 3: Just Security cited CAC’s brief in an article discussing the amicus briefs filed in Learning Resources v. Trump. “A SCOTUS Bench Memo for the Trump Tariff Case: Separation of Powers, Delegation, Emergencies, and Pretext”
• November 2: CAC President Elizabeth Wydra joined Canadian Broadcasting Corporation to discuss Learning Resources v. Trump. “Trump’s tariffs face biggest test yet in U.S. Supreme Court”
• October 29: CAC Vice President Praveen Fernandes was quoted as co-chair of the Not Above the Law coalition in Common Dreams’ piece covering the Trump administration’s deployment of national guard troops to U.S. cities. “‘Unlawful and Un-American’: Trump Claims He Can Send ‘Army, Navy, Air Force, Marines’ Into US Cities”
• October 24: CAC’s brief was cited in an article from International Trade Today on the amicus briefs filed in Learning Resources v. Trump. “Legion of Amicus Briefs Filed at SCOTUS to Contest IEEPA Tariffs”
• October 24: CAC Vice President Praveen Fernandes was quoted as co-chair of the Not Above the Law coalition in Common Dreams’ piece covering the Trump administration’s weaponization of the Department of Justice. “Majority of Americans Agree Trump Is Weaponizing DOJ to Target Political Enemies”
• October 21: CAC’s brief was cited in a Slate article discussing Illinois v. Trump. “Trump’s Crackdown on Portland Is Bad Enough. One Judge Has a Plan to Make It Worse.”
• October 17: CAC Vice President Praveen Fernandes was quoted as co-chair of the Not Above the Law coalition in Common Dreams’ article covering the indictment of John Bolton. “Indictment of Ex-Trump Adviser John Bolton Called a ‘Warning Shot to Every American’”
• October 17: An American Bar Association article discussing Case v. Montana cited CAC’s brief. “ABA Supreme Court Preview: Case v. Montana”
• October 16: Professor Steve Vladeck cited CAC’s brief in Illinois v. Trump in a recent article on his Substack, One First. “Bonus 183: Martin v. Mott”
• October 15: CAC Director of the Human Rights, Civil Rights, and Citizenship Program David Gans was quoted in an article by Medill News Service discussing Louisiana v. Callais and the Voting Rights Act. “Supreme Court seems skeptical of key provisions in Voting Rights Act”
• October 15: CAC’s brief was cited in an article in Slate on Louisiana v. Callais. “The Supreme Court Is Poised to Rule That It’s Racist to Remedy Racism”
• October 15: CAC Director of the Human Rights, Civil Rights, and Citizenship Program David Gans was quoted in a Courthouse News Service article on Louisiana v. Callais. “Supreme Court looks to neuter key protection for minority voters”
• October 10: News 10 quoted CAC Vice President Praveen Fernandes as co-chair of the Not Above the Law coalition in an article by News 10 covering the indictment of New York Attorney General Letitia James. “Retribution or accountability? New Yorkers respond to indictment of attorney general”
• October 8: CAC Director of the Human Rights, Civil Rights, and Citizenship Program David Gans was quoted in a Political Wire article discussing the Voting Rights Act. “Republicans Could Draw 19 More House Seats”
• October 8: Huff Post quoted CAC Deputy Chief Counsel Brian Frazelle in an article discussing Newsom v. Trump. “Yes, Stephen Miller Said Trump Had ‘Plenary Authority’ In A CNN Interview”

A Warm Welcome to CAC’s Newest Team Member!

CAC is pleased to welcome Janalie Cobb as our newest Paralegal and Research Associate, and to congratulate Lucy Resar on her promotion to Senior Research Associate. We were sad to say goodbye to Senior Research Associate, Alice Lesniak, but are excited for Alice’s next chapter.