Caitlin Halligan


212 390 9013

Photo of Caitlin Halligan

One of the nation’s leading appellate attorneys, Caitlin J. Halligan has argued six cases and served as counsel of record in more than 45 matters in the U.S. Supreme Court, and has handled scores of cases in the federal appellate courts, the New York Court of Appeals, and other state appellate courts. She has been praised for her “impressive track record” by Chambers USA, named one of the “Top 250 Women in Litigation” by Benchmark Litigation, and recognized as one of Crain’s “100 Notable Women in Law.”

Caitlin served as solicitor general for the State of New York from 2001 to 2007, after serving as deputy solicitor general. Before that, she served as the first chief of the New York attorney general’s Internet Bureau, where she developed cutting-edge law enforcement and policy initiatives regarding online consumer fraud, securities trading, and privacy practices. Caitlin also served as general counsel to the New York County District Attorney’s Office. She currently teaches a seminar on state and public law as a lecturer on law at Harvard Law School, and previously taught a course on statutory interpretation and administrative law at Columbia Law School. She speaks frequently on topics that include appellate advocacy, the Supreme Court’s docket, and the impact of litigation brought by state attorney general offices.

Representative Matters

  • Won landmark decision from the New York Court of Appeals in Congel v.  Malfitano, which set forth standards for the dissolution of partnerships under New York law.
  • Led a coalition of former judges and prosecutors in filing an amicus curiae brief in People v.  Boone, in which the New York Court of Appeals addressed the reliability of cross-racial eyewitness identifications in criminal cases.
  • Argued en banc appeal before the U.S. Court of Appeals for the Second Circuit in Poventud v.  City of New York, which raised complex procedural questions about collateral attacks on the finality of criminal convictions.
  • Secured a reversal from the U.S. Supreme Court for New York State in City of Sherrill v. Oneida Indian Nation, in which the court clarified state and local government authority over lands once they are within tribal reservation boundaries.
  • Won a precedent-setting victory for New York counties in United Haulers Association v.  Oneida-Herkimer Solid Waste Management Authority, which established the authority of local governments to enact and implement solid-waste ordinances in the face of the dormant Commerce Clause.
  • Successfully represented life settlement investor Lavastone, an AIG affiliate, in a $1 billion RICO, fraud, and breach of contract case against defendants who purchased life insurance policies and sold them to Lavastone at inflated prices. Won dismissal of the defendants’ counter-claims at summary judgment. The trial resulted in a favorable settlement.
  • Successfully represented Chevron Corporation in an appeal of a RICO and civil fraud trial barring the enforcement of a fraudulently-obtained $9 billion judgment against Chevron.
  • Authored numerous amicus briefs before the U.S. Supreme Court on a range of constitutional, statutory, and procedural issues on behalf of diverse groups, including state attorneys general, local government officials, and private sector clients.

Caitlin has expertise in a broad variety of civil matters, including challenges to federal and state regulatory action, civil procedure, federal anti-discrimination law, RICO, and securities litigation. She has represented clients in high-stakes cases brought by the New York State Attorney General’s Office, and litigated numerous challenges to state and local government actions on constitutional, statutory, and administrative law grounds. During her tenure in the Manhattan District Attorney’s Office, Caitlin was involved in a wide range of criminal investigations and prosecutions, including the successful defense of a Fourth Amendment criminal procedure case in the U.S. Supreme Court. She has argued scores of civil and criminal cases for private sector clients, as well as New York state and local governments, before New York’s high court and the State intermediate appellate courts on a wide range of constitutional, statutory, and procedural issues.

Caitlin also has an active public interest practice. In 2018, she was appointed amicus curiae by the U.S. Court of Appeals for the Second Circuit in Schroete v. Barr to brief and argue issues related to the scope of an immigration judge’s authority in removal proceedings. Caitlin also recently authored an amicus brief in the New York Court of Appeals regarding use of eyewitness identification evidence, on behalf of former judges and prosecutors, as well as amicus briefs in a death penalty case before the U.S. Supreme Court, a reproductive rights case before the Eighth Circuit, and a case regarding liability of military service academies for sexual assault committed on campus before the Second Circuit. Caitlin previously served as pro bono counsel to the Board of the Lower Manhattan Development Corporation, an entity charged with leading the re-development of the World Trade Center site, and on several judicial selection committees.

Affiliations & Community Involvement

Caitlin earned her J.D., magna cum laude, from the Georgetown University Law Center and her B.A., cum laude, from Princeton University. She clerked for the Honorable Justice Stephen Breyer of the U.S. Supreme Court and the Honorable Patricia Wald of the U.S. Court of Appeals for the D.C. Circuit. Caitlin is a member of the American Law Institute and a fellow of the American Academy of Appellate Lawyers. She serves on the board of Princeton-in-Asia, the Arc’s Criminal Justice Advisory Panel, and the New York County District Attorney’s Conviction Integrity Committee.

  • Georgetown University Law Center (J.D., 1995)
    Magna cum laude, Order of the Coif, Georgetown Law Review: Managing Editor; Olin Fellow in Law and Economics
  • Princeton University (B.A., 1988)
    Cum laude

  • Maryland Bar
  • New York Bar
  • Supreme Court of the United States
  • United States Courts of Appeals: First Circuit, Second Circuit, Third Circuit, Fourth Circuit, Fifth Circuit, Sixth Circuit, Ninth Circuit, Eleventh Circuit, and Federal Circuit
  • United States District Courts: Eastern District of New York, Southern District of New York