WILLIAM LEVI represents clients in all stages of litigation. He has extensive experience in both commercial disputes and government-facing litigation, including in matters defending against government enforcement actions and challenging federal regulatory action, and represents clients before federal administrative agencies as well as in federal and state courts. He also regularly advises clients on strategic legal issues arising from litigation, congressional investigations and subpoenas, and government investigations and regulation, including compliance with the Stored Communications Act, the INFORM Consumers Act, the Controlled Substances Act, and issues arising from international extradition. In recognition of his success, Will was named a “Future Star” in the District of Columbia by Benchmark Litigation (2025), and he is ranked among an elite group of lawyers as a 2023 “D.C. Rising Star” by The National Law Journal.
Before rejoining Sidley, Will served as Chief of Staff and Senior Counselor to the Attorney General at the U.S. Department of Justice. In that role, Will acted as the principal counselor to the Attorney General, and had broad responsibilities, including oversight of a wide range of high-profile civil litigation, criminal investigations and prosecutions, and national security matters. In recognition of outstanding service to the Department, Will was awarded the Department of Justice’s highest honor, the Edmund J. Randolph Award.
He also previously served as Chief Counsel to U.S. Senator Mike Lee and Staff Director of the U.S. Senate Judiciary Committee’s Subcommittee on Antitrust, Competition Policy, and Consumer Rights, which oversees the federal antitrust enforcement agencies and reviews major proposed mergers affecting the national economy.
Following law school, Will clerked for U.S. Supreme Court Justice Samuel A. Alito, Jr. and U.S. Court of Appeals for the Third Circuit Judge Anthony J. Scirica. By appointment of the U.S. Court of Appeals for the D.C. Circuit, Will serves as a member of the Court’s Advisory Committee on Procedures. He is also an elected member of the American Law Institute, a member of the Administrative Law & Government Litigation Advisory Committee of the U.S. Chamber Litigation Center, a member of the nominating committee for the William H. Webster Profiles in Leadership Award for Prosecution, and a former term member of the Council on Foreign Relations.