Meet Joe

Joseph M. Callahan, Esq., is a New York tax attorney with the law firm of Mackay, Caswell & Callahan, P. C.

All About Joseph M. Callahan, Esq.

Joe has over 35 years of experience representing clients with serious tax disputes involving the IRS and multi-state matters.  To learn more about Joe Callahan, read on…


Joe earned a B.S. in Public Relations from Syracuse University in 1981.  He then earned both a M.S. in Accounting and Juris Doctor from Syracuse University in 1986.

While in law school, Joe was a member of the Moot Court Board and was its Chair from 1984 – 1985. He received the prestigious Order of the Barristers and served as Moot Court Advisor to the University’s Vice Chancellor.  In that role, he worked extensively with the undergraduate Constitutional Law program.  Later, Mr. Callahan was a Research Assistant for the Law and Public Policy Department of the business school.

35 Years Experience
Avvo - Rate your Lawyer. Get Free Legal Advice. 7.6Joseph M. Callahan

In addition to his professional career, Joe has taught law and lectured on legal matters.  He’s taught at both Syracuse University and in multiple continuing legal education programs.

Experience Matters

Joe has a broad range of experience, which he can bring to bear on behalf of his clients. He’s worked in both the accounting and legal worlds, including at Deloitte, a “Big 4” accounting firm.  Both professions have exposed him to multiple tax controversies.  Both afforded Joe a unique perspective, which enables him to arrive at solutions in a timely and cost-effective manner.

Tax Matters

Throughout his years as a CPA and attorney, Joe has participated in several long-term audits and investigations.  They span the gamut and often have been initiated by specialized federal and New York State law enforcement agencies. Joe’s extensive tax experience includes a wide variety of high-profile investigations and prosecutions.  These have involved sales tax, income tax, tax fraud, immigration fraud, responsible person assessments, alien harboring and wire fraud.

Commercial Transactions

Joe also has extensive experience with commercial clients and lenders.  In addition, Joe routinely participates in numerous commercial transactions, asset purchases and sales, stock sales and business formations. His tax background has allowed him to successfully structure complex business transactions and, significantly, close those transactions.  These include bulk sales transactions, federal and state tax offers in compromise and offshore voluntary disclosure program (OVDP) submissions.

Learn More About Our Services

Joe’s achievements include the representation of several well-known individuals and businesses.  Joe has experience with tax evasion and tax fraud matters.  He also works with lenders, businesses and individuals conducting commercial transactions. If you’d like to learn more about our work and experience, please look at the blog posts on this website.

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