Patrick W. Martin is a U.S. tax lawyer licensed in California,  Washington D.C., and Texas and specializes in international tax and related international law matters.  He has practiced in the area for more than 32 years.  He and  is immediate family have lived, invested, studied (law, medicine, and business) and worked throughout Mexico over the last 30+ years.  

Mr. Martin is an international tax shareholder at Chamberlain Hrdlicka (a nationally ranked tax focused law firm, identified as the best law firm in tax and tax controversy in 2025 by Best Lawyers: “Law Firm of the Year”) where he practices exclusively in international tax.

He has advised clients for more than three decades regarding the U.S. international tax and related legal consequences of renouncing U.S. citizenship or abandoning lawful permanent residency.  He regularly represents individuals on all tax aspects of renouncing U.S. citizenship, and complications of lawful permanent resident status (including the tax treaty consequences). He successfully litigated the most important federal tax case recently on the subject regarding “green card” holders and tax treaties and tax expatriation.  See, Aroeste v United States – Order Nov 2023, that was appealed to the 9th Circuit by the Office of Solicitor General (DOJ) and ultimately conceded by the government.  U.S. District Court ruled in favor of green card holder. 

He has been identified by his peers in the Best Lawyers in America® (Tax Law) – 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024 & 2025.  He is a Fellow of the prestigious American College of Tax Counsel and a Fellow of the American College of Trust & Estates Counsel.

Outside of tax law, he is a passionate underwater cave explorer in the labyrinth of caves (thousands of kilometers) within the Yucatan peninsula.  He received membership into the Explorer’s Club in 2019 for his cave exploration work.  Founded in New York City in 1904, The Explorers Club promotes the scientific exploration of land, sea, air, and space by supporting research and education in the physical, natural and biological sciences. The Club’s members have been responsible for an illustrious series of famous firsts: First to the North Pole, first to the South Pole, first to the summit of Mount Everest, first to the deepest point in the ocean, first to the surface of the moon—all accomplished by [Explorer’s Club] members.

He is a past Chair of the Taxation Section of the State Bar of California, Taxation Section.  He was awarded the V. Judson Klein Award by the Taxation Committee of the State Bar of  California in 2010.  He received his law degree, J.D. from the University of San Diego School of Law, where he received the distinguished alumni award in 2013.  He passed the Certified Public Accountant’s exam in the 1980s, previously worked for the Internal Revenue Service, and studied postgraduate law studies in international law – business transactions at the Escuela Libre de Derecho, in Mexico City in the 1990s.

He is the U.S. tax professor in charge of the executive international tax program at ITAM (Instituto Tecnológico Autónomo de México) in Mexico City with the University of San Diego School of Law.

He represents individuals and companies in international business and realted tax planning.  He also represents clients before the IRS in international tax audits and litigates against (i) the IRS vis-à-vis the Office of Chief Counsel lawyers (in U.S. Tax Court) and (ii) attorneys from the Tax Division, Department of Justice (in U.S. District Court and the U.S. Court of Federal Claims).  Reach him at 210-278-5835 or patrick.martin@chamberlainlaw.com