Andrew Lyonsberg focuses his practice on litigation in the Supreme Court and appellate courts across the country, as well as major motions at the trial-court level. He has briefed more than fifty appellate matters and dispositive motions, and has argued before the US Courts of Appeals for the Fifth, Sixth, and Seventh Circuits. Andrew also has extensive experience with agency litigation under the Administrative Procedure Act, including several recent victories setting aside federal agency action.
Andrew has been recognized in Best Lawyers: Ones to Watch (2023) for appellate practice, and was named a Rising Star in Supreme Court and appellate litigation by The Legal 500 (2022). He was also featured in the 2021 edition of The Legal 500, with clients praising his “big-picture thinking” and “sophisticated view on how the executive branch operates.”
Andrew served as a law clerk to the Honorable Kim McLane Wardlaw on the US Court of Appeals for the Ninth Circuit. While in law school, he was a forum editor of the Yale Law Journal.
Obtained a Supreme Court victory expanding judicial review over administrative decisions on Convention Against Torture claims. (Nasrallah v. Barr)
Won a complex statutory-interpretation decision in the Supreme Court securing a favorable construction of the Immigration and Nationality Act. (Guerrero-Lasprilla v. Barr/Ovalles v. Barr)
Obtained a permanent nationwide injunction on behalf of a consortium of leading colleges and universities, blocking an immigration policy detrimental to the interests of international students. (Guilford College v. Wolf, M.D.N.C.)
Helped secure a Supreme Court win in a case that significantly narrowed the administrative law doctrine of Auer deference. (Kisor v. Wilkie)
The Best Lawyers in America, Ones to Watch in Appellate Practice, 2023 to 2024
The Legal 500 US, Rising Star in Appellate & Supreme Court Litigation, 2022
The Legal 500 US, Appellate & Supreme Court Litigation, 2021 to 2023
Yale Law School, JD, 2016
Williams College, BA, magna cum laude, 2011
Courts / Agencies US Supreme Court
US Court of Appeals for the Second Circuit
US Court of Appeals for the Fourth Circuit
US Court of Appeals for the Fifth Circuit
US Court of Appeals for the Sixth Circuit
US Court of Appeals for the Seventh Circuit
US Court of Appeals for the Ninth Circuit
US Court of Appeals for the District of Columbia Circuit
US District Court for the District of Columbia
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