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Nicholas S. Bahnsen

Nicholas S. Bahnsen




Washington, D.C.
T: 202.875.8000
F: 202.844.3500

Nicholas S. Bahnsen is an experienced litigator whose practice focuses on complex commercial disputes involving international tax and securities fraud matters, federal tax controversies, and white-collar criminal defense.

Nick has significant experience coordinating all phases of civil litigation, including particular experience with federal multidistrict litigation, international discovery requests under the Hague Convention, and evidence of foreign law under Rule 44.1 of the Federal Rules of Civil Procedure. He has taken numerous depositions, drafted a variety of pleadings and substantive briefs, and coordinated electronic discovery in matters involving tens of millions of documents. Nick’s practice routinely involves close collaboration with outside domestic and international law firms and accounting firms pursuant to common interest and joint defense agreements.

Nick joined Kostelanetz LLP in 2019 after nearly four years as a trial attorney with the U.S. Department of Justice Tax Division. While at the Department of Justice, Nick successfully tried jury and non-jury cases while managing a full docket of civil matters. He appeared regularly in U.S. District Court and Bankruptcy Court, obtaining civil injunctions against tax preparers and businesses with serial employment tax deficiencies, collecting millions in unpaid taxes, penalties and interest, and defending the government in tax-related civil suits. He received the DOJ Tax Division Outstanding Attorney Award in 2017.

Nick received his B.A. summa cum laude in public policy with a minor in accounting from the College of William and Mary in 2008 and his J.D. from the Vanderbilt Law School in 2012. Nick served as the Executive Authorities Editor of the Vanderbilt Journal of Transnational Law.

Vanderbilt University Law School, J.D. (2012)

College of William and Mary, B.A. (2008), summa cum laude

New York

New Jersey

District of Columbia

U.S. District Court for the Southern District of New York

U.S. District Court for the Eastern District of New York

U.S. District Court for the District of Columbia

U.S. District Court for the District of New Jersey