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Tax Law Legal Research: Tax Code and Treasury Regulations

U.S. Constitution

Relevant sections of the Constitution and Bill of Rights:

  • Art. I, Sec. 8: "The Congress shall have Power To lay and collect Taxes, Duties, Imposts and Excises..." Also includes the Commerce Clause, which impacts taxation related to interstate and foreign commerce.
  • Amend. XVI: "The Congress shall have power to lay and collect taxes on incomes, from whatever source derived, without apportionment among the several States, and without regard to any census or enumeration."
  • Art. I, Sec. 7: "All Bills for raising Revenue shall originate in the House of Representatives..."
  • Art. I, Sec. 2: Direct taxes should be apportioned by population.
  • Art. I, Sec. 9: "No Tax or Duty shall be laid on Articles exported from any State."
  • Art. I. Sec. 10: States are generally prohibited from taxing imports or exports without the consent of Congress.

U.S. Tax Code

The vast majority of statutes related to income, estate and gift, excise, and employment taxes are contained in Title 26 of the U.S.C. This is generally referred to as the Internal Revenue Code. The current code was promulgated in 1986, though it has been amended many times since (and thus should be referred to as the "Internal Revenue Code of 1986, as amended"). It replaced two previous versions from the 1939 and 1954.

The Code is divided into subtitles, which are further divided into chapters and subchapters. Using these subtitles, chapters, etc. can be a good way to find relevant Code sections, as they are organized topically. Browsing the table of contents for the code can lead you to relevant provisions.

Subtitle   Subject
A Income Taxes
B Estate and Gift Taxes
C Employment Taxes
D Misceallaneous Excise Taxes
E Alcohol, Tobacoo, and Certain Other Excise Taxes
F Procedure and Administration
G The Joint Committee on Taxation
H Financing of Presidential Election Campaigns
I Trust Fund Code
J Coal Industry Health Benefits
K Group Health Plan Requirements

Treasury Regulations

The Internal Revenue Code gives the Treasury Department the authority to make regulations related to the Code. The department issues three types of regulations: proposed, final, and temporary.

  • Proposed regulations are published in the Federal Register daily, and the public is given a period to comment on the regulations before they move to their final version. Treasury Department proposed regulations are also reprinted in the Internal Revenue Bulletin (I.R.B.) which comes out weekly, and is compiled twice a year into the Culmulative Bulletin (C.B.).
  • Final regulations are issued after the department takes comments on a proposed regulation into account. They are first published as Treasury Decisions, which have a four-digit citation such as T.D. 8597, as well as in the Federal Register. Final regulations are codified into the Code of Federal Regulations (C.F.R.), which is published yearly, and are given a citation referring to the Code section they address. For example, a regulation on Sec. 37 of the Internal Revenue Code is labeled as 1.37-2, where the 1 indicates that it is a Treasury regulation, 37 refers to the code section, and 2 indicates the regulation number.
  • Temporary regulations are effective as soon as they are published in the Federal Register and are intended to provide immediate, short-term guidance on new tax statutes. They are also published as Treasury Decisions and codified in the Code of Federal Regulations.