John Gleeson is a trial and appellate lawyer and company advisor who was a federal judge for 22 years before joining the firm in 2016. He is a litigation partner in the White Collar & Regulatory Defense and Commercial Litigation Groups. A fellow of the American College of Trial Lawyers, Judge Gleeson’s practice focuses on white collar defense, complex civil litigation, internal investigations, and dispute resolution. Since joining Debevoise, Judge Gleeson has argued cases in numerous federal and state courts of appeals, conducted trial proceedings in federal and state courts, appeared in multiple bankruptcy proceedings, acted as both a mediator and arbitrator in commercial disputes, conducted independent investigations, advised boards of directors on corporate governance matters, and provided expert testimony on United States law in multiple foreign tribunals. Judge Gleeson has also been appointed as amicus curiae on three occasions in separate federal courts to argue important issues of federal criminal law and procedure, including to make the argument against the government’s motion to dismiss the prosecution of former National Security Advisor Michael Flynn.

Judge Gleeson is ranked as a leading lawyer in White Collar-Crime and Government Investigations by Chambers USA (2021), where clients describe him as “a thought leader” and “a skillful trial lawyer with great judgment.” He is also recommended by The Legal 500 US (2021) for International Litigation.

Prior to joining the firm, Judge Gleeson was a United States District Judge in the Eastern District of New York, sitting in Brooklyn. While a judge, Judge Gleeson authored more than 1,500 published opinions (including 14 opinions for the United States Court of Appeals for the Second Circuit, sitting by designation). He also presided over more than 200 civil and criminal jury trials. He was assigned numerous Multidistrict Litigations, including two antitrust class actions against Visa and MasterCard and the Air Cargo antitrust cases. Judge Gleeson served on the Judicial Conference Committee on Defender Services for nine years (including three years as Chair). The Defender Services Committee is responsible for the nearly $1 billion per year program that provides effective defense counsel to the 80% of federal defendants who cannot afford to retain counsel.

Before his appointment to the bench in 1994, Judge Gleeson was a federal prosecutor in the same courthouse for 10 years. He served as Chief of Appeals, Chief of Special Prosecutions, Chief of Organized Crime and Chief of the Criminal Division. He personally tried 20 cases to verdict, argued 25 appeals in the United States Courts of Appeals for the Second Circuit, and also argued appeals in Third and Sixth Circuits. Among the numerous high-profile cases he tried, Judge Gleeson was the lead prosecutor in the murder and racketeering convictions of John Gotti and Victor Orena, the bosses of the Gambino and Colombo Families of La Cosa Nostra, respectively. Judge Gleeson received the Attorney General’s Distinguished Service Award for his service in the Gotti case.

Prior to becoming a federal prosecutor, Judge Gleeson was a litigation associate at Cravath, Swaine & Moore for four years and a law clerk for the Hon. Boyce F. Martin, Jr. on the United States Court of Appeals for the Sixth Circuit.

Judge Gleeson has taught law for more than 30 years. He currently teaches Complex Federal Investigations at Harvard Law School and Sentencing at New York University School of Law and Yale Law School. He was the John A. Ewald, Jr. Distinguished Visiting Professor of Law at the University of Virginia School of Law. He has guest lectured at Yale Law School, Columbia Law School, Stanford Law School, Cornell Law School, University of Michigan Law School, Fordham Law School, Brooklyn Law School, and Cardozo School of Law. He is a co-author of the widely used treatise Federal Criminal Practice: A Second Circuit Handbook (LexisNexis), which is now in its 20th edition.

Judge Gleeson is a fellow of the American College of Trial Lawyers, a member of the American Law Institute, a trustee of the Vera Institute of Justice, a member of the Advisory Boards of the Program on Corporate Compliance and Enforcement and the Center on Civil Justice at NYU School of Law, and a member of the Board of Directors of the Federal Defenders of New York.

Judge Gleeson’s other publications include "Judicial Scrutiny of NPAs and DPAs,” (Chapter in The Guide to Monitorships, Global Investigations Review (2019); “The Ulysses Cases and What They Reveal About Lawyers and the Law,” James Joyce Quarterly (2015); a chapter titled “Objections” in Winning at Trial: Insights From the Bench and Leading Litigators (2014); “The Sentencing Commission and Prosecutorial Discretion: The Role of Courts in Policing Sentencing Bargains,” Hofstra Law Review (2008); “The Road to Booker and Beyond: Constitutional Limits on Sentence Enhancements,” Touro Law Review (2006); “Supervising Federal Capital Punishment: Why the Attorney General Should Defer When U.S. Attorneys Recommend Against the Death Penalty,” Virginia Law Review (2003); “Supervising Criminal Investigations: The Proper Scope of the Supervisory Power of Federal Judges,” Journal of Law and Social Policy (1997); “Sentence Bargaining Under the Guidelines,” Federal Sentencing Reporter (1996); and “The Federalization of Organized Crime: The Advantages of Federal Prosecution,” Hastings Law Journal (1995).

Judge Gleeson’s awards include the following: The Gould Award for Outstanding Oral Advocacy, Office of Appellate Defender’s First Monday in October (2019); The National Legal Aid and Defender Association’s Exemplar Award (2018); The Client Service All-Star Award, BTI Consulting Group (2018); The Thomas Jefferson Foundation Medal in Law, University of Virginia (2016); Honorary Doctor of Laws, Northern Kentucky University (2016); The Distinguished Jurist in Residence, Cornell Law School (2016); The Distinguished Jurist Award, Defense Association of New York (2016); The Judicial Recognition Award, National Association of Criminal Defense Lawyers (2015); The Hon. William Brennan Award for Outstanding Jurist, New York State Association of Criminal Defense Lawyers (2014); The Green Bag Exemplary Writing Award, for United States v. Dossie (2013); The Green Bag Exemplary Writing Award, for United States v. Ovid (2011); Special Recognition Award, New York Criminal Bar Association (2009); and The Hon. Edward Weinfeld Award, New York County Lawyers’ Association (2008).

Judge Gleeson earned his J.D from the University of Virginia School of Law in 1980 and his B.A. from Georgetown University in 1975.

Recent speaking engagements include:

  • The Leslie H. Arps Memorial Lecture, New York City Bar Association forthcoming in Spring 2021, New York, New York.
  • Advanced Topics in Law and Public Service, November 2020, University of Virginia School of Law
  • Pennsylvania Association of Criminal Defense Lawyers, White Collar Seminar, November 2020
  • Sentencing Symposium, Stepping Up Implementation of the First Step Act, American Criminal Law Review, October 2020, Georgetown University Law Center
  • Access and Accountability 2020: Lessons of the Current Moment, October 2020, Yale Law School


  • University of Virginia School of Law, 1980, J.D.
  • Georgetown University, 1975, B.A.

Bar Admissions

  • New York