Guinevere Moore

Practice Areas

Tax Litigation

Tax Controversy

Career

Guinevere Moore represents taxpayers in significant disputes with the Internal Revenue Service, the Department of Justice, Tax Division, and state taxing agencies. She is the Managing Member of Moore Tax Law Group, LLC, a tax controversy and tax litigation firm with an office in Chicago.

Guinevere has over fifteen years of experience helping taxpayers resolve significant disputes with the IRS and state tax agencies. She routinely represents taxpayers in high-stakes criminal and civil tax disputes. At Moore Tax Law Group LLC, we take a holistic approach to representing clients. We believe the only way to accomplish the best possible outcomes for our clients is by truly getting to know our clients. Some clients want to win at all costs. Some clients want to resolve the issue as quickly as possible, and are willing to concede issues they would likely win in litigation in order to put the problem with the IRS behind them. Most fall somewhere in between. Guinevere gets to know her clients and ensures that she has a deep understanding of their needs and preferences before developing a strategy for the case.

She is a frequent speaker and author, routinely publishing articles and speaking at conferences around the world on tax controversy and tax litigation in Forbes, Bloomberg, and Tax Notes. Guinevere lives in Chicago with her husband and their four children.

Professional Memberships

Guinevere is an active member of the tax bar.  She is an active member of the American Bar Association, Section of Taxation.  She is currently serving on Council and has previously served as the chair of the Standards of Tax Practice Committee. In that role, she helps design and implement continuing education seminars for attorneys and tax professionals focusing on civil and criminal tax disputes and tax ethics.

Publications

Guinevere Moore on balancing tax litigation with childcare and ‘paying it forward,’ International Tax Review, March 24, 2026.

The IRS is Losing the Paper Chase, Forbes, February 7, 2026.

ERC Disallowances Under OBBA Are Here, Forbes, February 5, 2026.

Sirius Solutions Delivers IRS Serious Blow When Taxing Limited Partners, Forbes, February 3, 2026.

Responding To IRS Form 105C Denying Your ERC Claim – A How-To Guide, Forbes, January 26, 2026.

Welcome News From The IRS: The Voluntary Disclosure Program Is Changing. Forbes, December 15, 2025.

National Taxpayer Advocate Urges IRS To Clear The ERC Backlog. Forbes, December 3, 2025.

Taking the Taxman to Court is Complicated by Government Shutdown. Bloomberg Law, October 17, 2025.

ERC Updates from the OBBA and Beyond. Tax Notes, August 26, 2025.

Looking For A Way To Settle An IRS Dispute? Try A Qualified Offer. Forbes, May 29, 2025.

Employee Retention Credit: Potential Penalties, (Co-Authored), Tax Notes, March 28, 2025.

The Path to Challenging an Ignored, Disallowed, or Clawed-Back ERC Refund Claim, (Co-Authored), Tax Notes, March 18, 2025.

Employee Retention Credit That Turned Into a Billion Dollar Debacle, (Co-Authored), Tax Notes, March 6, 2025.

Experience

Civil Tax Defense

Guinevere represents taxpayers in significant civil tax disputes of all kinds – assessable penalties, income, estate, gift, payroll, excise, and sales tax. She has resolved tax disputes on behalf of individuals, partnerships, corporations, trusts, and estates.

Every taxpayer wants to resolve their case with the IRS without litigation, and it is always our goal to work with the IRS to try to reach an agreement administratively. Guinevere has assisted taxpayers in resolving disputes with the IRS at the examination level and at IRS appeals, and these agreements reached without litigation are often the most rewarding.

If an agreement with the IRS can’t be reached, Guinevere has significant experience litigating on behalf of her clients. She has acted as lead counsel for taxpayers in United States Tax Court, Federal District Court, and the Court of Federal Claims, as well as in Courts of Appeal around the country, including the Seventh Circuit, the Eleventh Circuit, and the D.C. Circuit. She has litigated on behalf of taxpayers in the Supreme Court of the United States representing amicus curie, twice leading to taxpayer favorable outcomes.

In recent years Ms. Moore has increased her representation of clients in valuation matters, including representing appraisers and taxpayers defending valuations. She is defending clients against imposition of various penalties associated with technical foot-faults associated with appraisals and the technical guidelines set forth in Treasury Regulations 26 CFR section 1.170A-14 and associated regulations.

Criminal Tax Defense and White Collar Defense

Guinevere and the Moore Tax Law Group team represent clients in federal criminal tax investigations and white collar cases all over the country. Most of Guinevere’s criminal tax and white collar defense work is on cases no one has ever heard of and never will. That is because no one wants to “win” a criminal tax case, they want the case to be resolved without formal charges ever being brought. Guinevere works to resolve her cases quietly, cooperatively, by demonstrating why the government should not bring charges.

If it is not possible to avoid charges entirely, Guinevere will work to accomplish her client’s individual objectives to resolve the case. This can mean working with the government to craft a creative plea and sentencing agreement, or it might mean going to trial. The decision of whether to accept a plea or proceed to trial is a deeply personal one for each criminal defendant, and Guinevere works with her clients to ensure that they have all of the information necessary to make the best decision possible.

If a client decides to go to trial, Guinevere and her team are ready and experienced. The Pew Research Center recently reported that fewer than 1% of federal criminal defendants were acquitted in 2022. Moore Tax Law Group secured a complete acquittal in the summer of 2023 after a twelve-week jury trial of their client in the Northern District of Georgia with Guinevere Moore as lead counsel.

Personal

After her twin boys were born two months early and spent two months in the NICU, Guinevere was introduced to the March of Dimes.  They are alive today due in large part to the life-saving treatment that the March of Dimes developed.  Guinevere and her husband have since become members of the Chicago Board of Directors of that organization and are actively involved in helping improve the health of all moms and babies.

Her favorite charities to support include the  Irving Park Food Pantry,  The Chicago Park District,  Friends of Disney II, and  Hamlin Park Baseball Association.

Awards

Education

Expert in these Jurisdictions

Tax Controversy & Litigation