Denis J. Conlon
Denis J. Conlon
Denis J. Conlon is of counsel at Martin, Brown, Sullivan, Roadman, & Hartnett, Ltd.  Mr. Conlon has over 50 years of experience litigating cases and counseling clients in federal tax matters, both civil and criminal.  He provides advice and representation in matters requiring detailed knowledge of Internal Revenue Service ruling, examination, appeals, litigation and other IRS procedural matters in the most difficult cases.   His experience includes the IRS Industry Specialization Program, primarily exempt organizations, insurance and tax shelters. 
Prior to working at Martin, Brown, Sullivan, Roadman, & Hartnett, Ltd., Mr. Conlon served in the IRS Office of Chief Counsel as Regional Counsel, Midwest Region and District Counsel, Chicago Office.  He also worked at Ernst & Young, LLP as its Director of IRS Controversy, Great Lakes Region.

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Loyal University of Chicago, J.D., 1961
Depaul University College of Law, LL.M (Taxation), 1985
Loyal University of Chicago, B.S.C., 1958

Bar Admissions


Court Admissions

Northern District of Illinois
United States Tax Court
United States Court of Claims
United States Court of Appeals for the Seventh Circuit

Notable Cases and Results

Burr Oaks Corp. v. Commissioner, 43 T.C. 635 (1965), sale versus I.R.C. § 351, and debt versus equity issues (Tried Tax Court case for IRS)
Ross Glove Co. v. Commissioner, 60 T.C. 569 (1973), I.R.C. § 482 applied to glove manufacturing in international setting (Tried Tax Court case for IRS)
Otto Kerner, Jr. v. Commissioner, T.C. Memo 1976-12 (1976), value of historical papers determined for charitable contribution (Tried Tax Court case for IRS).

USFreightways Corp. v. Commissioner, 113 T.C. 329 (1999), reversed and remanded, 270 F.3d 1137 (7th Cir. 2001). One-year rule on capital expenditure versus ordinary business expense. Court of Appeals reversing Tax Court in favor of taxpayer. (Provided technical assistance for taxpayer).
G5 Investment Partnership v. Commissioner, 128 T.C. 186 (2007). Statute of limitations regarding §§ 6229 and 6501 (Trial counsel for Petitioner)
L.R. Development Company, LLC v. Commissioner, T.C. Memo 2010-2031 (2010). Transferee Liability, I.R.C. § 6901, Mid Co. Transaction (Trial counsel for Petitioner)

Chandler v. Commissioner, 142 T.C. No. 16 (2014). Value of historic easement determined (Trial counsel for Petitioners)

Estate of Franklin Z. Adell v. Commissioner, T.C. Memo 2014-155.  Estate tax, value of stock determined (Trial counsel for Petitioner)

Law School Honors/Involvement

Phi Alpha Delta

Employment History

Attorney, Office of Chief Counsel, Internal Revenue Service
Staff Assistant to Regional Counsel, Office of Chief Counsel, Internal Revenue Service
Assistant Regional Counsel, Tax Litigation, Office of Chief Counsel, Internal Revenue Service
District Counsel - Chicago, Office of Chief Counsel, Internal Revenue Service
Regional Counsel - Midwest Region , Office of Chief Counsel, Internal Revenue Service
Director IRS Controversy - Great Lakes Region, Ernst & Young, LLP

Bar/Professional Association Involvement

Chicago Bar Association
Wisconsin Bar Association
American Bar Association - Tax Section
Adjunct Professor - Chicago Kent College of Law, Tax Crimes and IRS Practice and Procedure
Served as an instructor in the Chief Counsel’s Advance Advocacy School in Williamsburg, Virginia and as lead instructor in Chief Counsel’s Trial Attorney training program in Washington, DC
Served as an instructor for Ernst & Young, LLP in IRS Practice, Insurance Taxation and Exempt Organizations
Served as Co-Chair of IRS Large and Mid-Sized Business, Subcommittee of Tax Section of ABA in 2004

Community Involvement

Chairman of Chief Counsel’s Business Review Council
Board Member - Chief Counsel’s Information Management Policy Board
Board Member - IIT Kent Federal Tax Institute
Board Member - IIT Kent Not-for-Profit Conference

Published Legal Writing

Co-author of “Tax Court from the IRS Perspective,” a chapter in Federal Civil Tax Practice, published by the Illinois Institute of Continuing Legal Education

Legal Lectures

Presented on numerous legal subjects for Chicago Bar Association, Federal Bar Association, Ernst & Young, LLP and American Bar Association - Tax Section

Subjects include:
Use of Expert Witnesses in Tax Cases
Alternative Dispute Procedures in Tax Cases
IRS Reorganization of 1998
Use of Statistical Sampling in Tax Cases
Use of Substance over Form by Taxpayers
I.R.C. § 482 Cases in Tax Court
Tax Preparer Penalties


Presidential Rank Award, Meritorious Executive - 1991
Secretary of Treasury Award - 1986
IRS Commissioner’s Award - 1992
General Counsel’s Award - Treasury - 1992