Skip to Content

Erin A. O’Brien is a partner in the firm’s Corporate Department, specializing in Tax Certiorari. She has successfully obtained millions of dollars in real estate tax savings for clients, including national, regional and local owners and tenants of all types of commercial, industrial and residential properties. Her extensive litigation experience in both the Supreme and Appellate Courts throughout New York has led to the establishment of significant legal precedents in the field.

As a founding member of Women in Tax Assessment, Erin is dedicated to advancing diversity and inclusion within her profession. She also contributes her expertise as a member of the associate board of the Association for a Better Long Island. Erin is a frequent guest speaker and has shared her insights at numerous symposiums throughout New York State.

Practice Areas



  • New York
  • Connecticut
  • U.S. District Court for the Eastern District of New York
  • U.S. Court of Appeals for the Second Circuit
  • U.S. Supreme Court


  • J.D., City University of New York Law School, 2005
  • B.A., North Carolina State University, 1996

Professional and Community Activities

  • Member, New York State Bar Association
  • Member, Nassau County Bar Association
  • Member, Suffolk County Bar Association
  • Member, New York City Bar Association, Condemnation and Tax Certiorari Committee
  • Associate Board Member, Association for a Better Long Island
  • Founding Member, Women in Tax Assessment
  • Member, New York State Assessors’ Association
  • Member, Institute for Professionals in Taxation
  • Committee Member, CIBS-W Commercial Industrial Brokers Society

Honors and Awards

  • New York Metro Super Lawyers, 2023
  • “Top 50 Women in Business,” Long Island Business News, 2023
  • “Who’s Who in Tax Certiorari Law,” Long Island Business News, June 2022
  • “Women in Real Estate,” New York Real Estate Journal, September 2019


  • “The Effects of COVID-19 on Property Taxes,” The Legal Brief
  • The ‘Dark Store’ dilemma – When Assessors Disregard Fee Simple Valuation, New York Real Estate Journal 
  • “Property tax exemptions: Are you paying more property taxes than you should be?” New York Real Estate Journal
  • “Home Team Advantage?: The Taking of Private Property for Sports Stadiums,” New York City Law Review