Argi O’Leary

Overview

Argi O’Leary is a Principal in Ryan’s Controversy Resolution practice, based in the Firm’s New York office. She advises clients on complex tax disputes across all tax types, providing strategic guidance on audit assistance, issue negotiation, policy interpretation, and advocacy before taxing authorities. Argi partners closely with clients to navigate high-stakes examinations and enforcement matters with clarity, discipline, and effective resolution strategies.

Argi brings deep experience from senior leadership roles within government, the judiciary, and private practice. Her background includes service as Deputy Commissioner and Assistant Deputy Commissioner at the New York State Department of Taxation and Finance, where she oversaw significant tax administration and enforcement functions. She also served as a federal law clerk and as an Assistant District Attorney in New York County, shaping her strong litigation judgment and regulatory insight. In addition to client service, Argi contributes to tax administration policy through her current service on the D.C. Office of Tax & Revenue’s Tax Advisory Board, her former service on the Internal Revenue Service’s Electronic Tax Administration Advisory Committee, and as a frequent speaker on state and local tax controversy topics.

Education and Qualifications

Juris Doctor, Fordham University School of Law

Master of Science, Boston College

Bachelor of Arts, Boston College

Licensed Attorney, New York and New Jersey (Ryan is not a law firm.)

Experience and Achievements

Principal, Controversy Resolution, Ryan, New York office

• Advises clients on audit defense, issue resolution, and tax controversy strategy across all tax types

• Provides policy analysis and advocacy before state and local taxing authorities

Private Law Practice

Deputy Commissioner, New York State Department of Taxation and Finance

Assistant Deputy Commissioner, New York State Department of Taxation and Finance

Federal Law Clerk, U.S. District Court, Eastern District of New York

Assistant District Attorney, New York County District Attorney’s Office

Volunteer Member, D.C. Office of Tax & Revenue’s Tax Advisory Board

Volunteer Member, Electronic Tax Administration Advisory Committee, Internal Revenue Service

Trustee, Board of Education, Voorheesville Central School District

Member, Institute for Professionals in Taxation

Member, Streamlined Sales Tax™ Governing Board, Inc., Business Advisory Council