David Zimmer

David Zimmer is a partner at Zimmer, Citron & Clarke, which he co-founded in 2025. David has extensive experience representing clients in appeals and complex civil litigation. David has argued or second-chaired seven merits cases at the U.S. Supreme Court and dozens of appeals in federal and state appellate courts across the country. He also regularly assists with dispositive motions in federal and state trial courts.

David dedicates a significant portion of his time to pro bono work and public service, with a particular focus on immigration law. He successfully argued two of the most important immigration cases the Supreme Court has decided in the last decade: Pereira v. Sessions and Niz-Chavez v. Garland. Massachusetts Attorney General Maura Healey also appointed David as Special Assistant Attorney General to represent District Attorneys Marian Ryan and Rachael Rollins in their challenge to ICE’s practice of civilly arresting those appearing in Massachusetts courts, which led to a first-of-its-kind preliminary injunction against the practice. David is one of the few two-time winners of the American Immigration Lawyers Association’s Jack Wasserman Memorial Award for Excellence in Litigation.

In addition to his litigation work, David serves on the Board of Directors of both the ACLU of Massachusetts and Lawyers for Civil Rights, is the Chair of the AILA Amicus Committee and a member and the former co-Chair of the Boston Bar Association’s Amicus Committee, and is on the Legal Services Corporation’s Leaders Council.

Prior to co-founding Zimmer, Citron & Clarke, David was a partner in Goodwin Procter’s Supreme Court and Appellate practice and clerked for Justice Elena Kagan of the U.S. Supreme Court and Judge William A. Fletcher of the U.S. Court of Appeals for the Ninth Circuit. He graduated from Harvard Law School in 2010.