Marianna C. Chapleau is a litigation of counsel in Kirkland’s New York office.

Prior to joining Kirkland, Marianna served as a law clerk to Judge Jacques L. Wiener, Jr. of the U.S. Court of Appeals for the Fifth Circuit, and before that, as a law clerk at the Office of the Solicitor General of Texas. Marianna also argued in front of the Fifth Circuit in her representation of pro bono clients in civil rights litigation.

With Kirkland, Marianna has acted as trial and appellate counsel and has broad experience in complex commercial litigation, including breach of fiduciary duty, fraud, breach of contract, shareholder derivative, and products liability matters. In addition, Marianna has represented pro bono clients in immigration and criminal proceedings.


Thought Leadership


Marianna C. Mancusi-Ungaro, Defining "Departure" in the Context of 8 CFR § 1003.4, 76 U. Chi. L. Rev. 467 (2009).

Memberships & Affiliations

Associate, The Honorable Patrick E. Higginbotham American Inn of Court (2012–2013)


Admissions & Qualifications

  • Not admitted to practice in New York
  • 2009, Texas (inactive)
  • 2013, Illinois (inactive)


  • United States Court of Appeals for the Fifth Circuit
  • United States District Court for the Northern District of Texas


  • University of Chicago Law SchoolJ.D.2009

    Managing Editor, The University of Chicago Law Review

    The Exoneration Project

    The Honorable Diane P. Wood International Law Summer Fellow

  • Yale UniversityB.A., Political Science & Spanishwith Distinction2004

    International Service and Social Justice REACH OUT Summer Fellow