Michael O’Donnell brings more than 30 years of experience inside the IRS Office of Chief Counsel, where he served in some of the most complex and consequential corners of federal tax litigation. A Chicago native, Mike began his academic path at DePaul University before earning his LL.M. in Taxation from Georgetown University Law Center, graduating first in his class and the first student to receive the honor of graduating “With Distinction” from the premier tax program in the country.

Mike began his legal career at the United States Tax Court. From there, he joined IRS Chief Counsel, where he would ultimately spend three decades shaping major tax controversies, developing expertise across litigation, criminal tax, money laundering, forfeiture, and high-stakes valuation matters.

A Litigator With Rare Experience

Mike built his early reputation in the IRS Small Business/Self-Employed Division, where he tried more Tax Court cases in an eight-year span than the vast majority of his peers. While many Chief Counsel attorneys settle valuation-heavy matters, Mike tried them; and won.

Valuation became one of his defining specialties:

• He is one of very few IRS attorneys to have tried multiple full Tax Court valuation opinions, rather than memorandum decisions.
  
• He was part of the litigation team in Bank One, the landmark case that defined the tax valuation of derivatives, effectively putting the financial industry on notice.
  
• His work includes a rare fully reviewed Tax Court opinion (Green-Thapedi v. Commissioner), where the entire Tax Court bench convened, something that occurs only for cases of exceptional importance.

   

Mike often jokes, with truth behind the humor, that among dozens of attorneys assigned valuation cases over the years, he alone holds the majority of trial-tested, real-world experience. His blend of deep tax knowledge, trial skill, and comfort with uncertainty makes him one of the most seasoned valuation practitioners in the country.

Criminal Tax, Forfeiture & Money Laundering Expertise

Later in his career, Mike transitioned to the Criminal Tax (CT) division, where he merged his tax background with his long-standing strength in criminal law. Mike reviewed and advised on hundreds of criminal prosecution reports, shaping the underlying tax and legal analysis DOJ relied on.

In CT, Mike became one of the IRS’s leading national authorities in:

• Forfeiture
• Money laundering
• Financial tracing and asset recovery

   

Colleagues across the Treasury Department routinely sought him out for these specialties, and he was widely regarded as one of the most knowledgeable practitioners in these highly technical areas.

Gordon Law

Mike’s three decades inside the IRS give him an uncommon ability to see tax controversies the way the government does; how cases are triaged, how agents evaluate evidence, what triggers escalation, and which facts truly matter. He can identify weaknesses before the government spots them and strengthen defenses long before a case turns adversarial. His trial experience is a rare asset in a field where few attorneys have ever taken a case through trial.

For Gordon Law, Mike is not simply an experienced practitioner; he’s a force multiplier, elevating our ability to defend clients with the same insight and precision the IRS once relied on.