Denaturalization of Zohran Mamdani's US citizenship before 2027 faces steep legal hurdles, driving trader consensus to a 90.5% implied probability on "No." The process requires Department of Justice civil proceedings to prove fraud or willful misrepresentation during naturalization, a rare step pursued in fewer than 100 cases annually, mainly against terrorists or Nazi collaborators. As a sitting New York State Assembly member naturalized in 2018 with no known investigations, indictments, or official actions against him, recent weeks show no DOJ filings, court rulings, or credible reports advancing such a case. Political immigration debates have not targeted Mamdani specifically, leaving scenarios like late scandals or executive actions as remote upset risks before the deadline.