LibGuides: Federal Tax Research: Historical Tax Research

Historical Tax Research

Historical tax research involves researching tax laws, regulations, and rulings that were in effect at a specific point in the past. This can be necessary for a variety of reasons, such as understanding the tax treatment of a past transaction, interpreting a provision of the current tax law that has its roots in older laws, or studying the history of tax policy.

Finding Historical Statutes

The Internal Revenue Code has been amended many times since it was first enacted. To find the version of a statute that was in effect at a specific point in the past, you can use a variety of resources:

Federal Tax Archives on Checkpoint Edge: This resource provides access to prior versions of the Internal Revenue Code going back to 1954.
United States Code on govinfo.gov: This government website provides access to editions of the United States Code going back to 1994.
Print Resources: Some law libraries have print copies of older editions of the United States Code or the Internal Revenue Code.

Checkpoint Edge (Thomson Reuters) This link opens in a new window
Specialized tax and accounting research tool, particularly useful for tax planning and compliance, accounting, audits, financial reporting, and related research, including specialized tax topics. Contains Research Institute of America (RIA) and Warren, Gorham & Lamont (WG&L) tax products, including Federal Treatises, Journals, and the WG&L Tax Dictionary. Researchers can also simultaneously search Checkpoint, IRS.gov, TEI, Big 4, and AICPA.
Researchers can view a Table of Contents for Checkpoint Edge by selecting [More] from the toolbar, then [Table of Contents]. Various general calculators can be found under [More] > [Tools], and [More] > [News] provides a stream of tax updates and access to the news library.
View the Checkpoint Edge Help Contents for detailed guidance to using the platform, including product training, quick reference documents, the Customer Help Center, Checkpoint Learning, and general updates and walkthroughs. Users can also select the icon of a question mark within a circle to access specific help whenever they see it.

Finding Historical Regulations

Treasury regulations are also subject to change. To find older versions of regulations, you can use resources like:

Federal Register on govinfo.gov: The Federal Register is the official publication for final and proposed federal regulations. Govinfo provides access to issues of the Federal Register going back to 1994.
Code of Federal Regulations on govinfo.gov: This resource provides access to editions of the Code of Federal Regulations (where final Treasury regulations are codified) going back to 1996.
Print Resources: Some law libraries have print copies of older editions of the Code of Federal Regulations.

Federal Register: The Daily Journal of the United States Government This link opens in a new window
The official daily publication for rules, proposed rules, and notices of Federal agencies and organizations, as well as executive orders and other presidential documents. Updated daily by 6 a.m. and is published Monday through Friday, except Federal holidays. Published by the Office of the Federal Register, National Archives and Records Administration (NARA). The Federal Register Index and List of CFR Sections Affected (LSA) are available on govinfo as separate publications. Learn more about the LSA.
Coverage is complete (1936+), and available in PDF and XML formats, which varies depending on issue.
To find a more recent, unofficial issue of the Federal Register, view the Public Inspection issue online at www.federalregister.gov, a service of the National Archives and Records Administration’s Office of the Federal Register. Individuals using this site may find useful the Reader Aids section, located at the bottom of the site.
About the Federal Register also covers: CFR Parts Affected, Unified Agenda, Searching, Sample URLs, Metadata Fields and Values, Related Resources, and FAQs.
Researchers should also utilize the GovInfo.gov website guidance located on the left-hand sidebar that covers Help, Finding Information, What's Available, Tutorials and Handouts, and Other Resources.
Code of Federal Regulations (Annual edition) This link opens in a new window
The Code of Federal Regulations (CFR) annual edition is the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. Those wanting the regularly updated online version, the e-CFR, should follow the link provided on the database. Also helpful are the Related Resources located at the end of the webpage.
Those relying on the CFR for legal research should verify their results against the most current official edition of the CFR, the daily Federal Register, and the List of CFR Sections Affected (LSA).
More information on understanding the eCFR.
The Getting Started guide also has a section on Digging Deeper into your research.
The eCFR website is jointly administered by by the Office of the Federal Register(OFR) of the National Archives and Records Administration (NARA) and the U.S. Government Publishing Office (GPO).

Finding Historical Case Law and Administrative Rulings

Historical case law and administrative rulings can often be found in the same places as current case law and rulings. Legal research platforms like Westlaw, Lexis, and Bloomberg Law provide access to cases and rulings going back many years. For very old materials, you may need to consult print resources or specialty databases like HeinOnline

HeinOnline This link opens in a new window
Database with many smaller collections, including the Law Journal Library, Historical Archives of State Statutes, Session Laws, English Reports, Federal Documents, and more. Odds are good that something you need is easily accessible in this database, which has extensive user support resources.
When using Hein, if you find you need help, click the Search Help link under the search box, or the Help link in the top information bar. Additionally, feel free to explore the items below.
Getting Started in HeinOnline.
Using HeinOnline.
HeinOnline Knowledge Base.
Hein's Tip of the Week.
HeinOnline's Suite of Tools.
What's New at Hein?

Understanding Historical Tax Law

Understanding historical tax law can be challenging, as the law may have been based on different principles or policy goals than the current law. Secondary sources can be very helpful in this regard. Treatises, law review articles, and other scholarly works can provide valuable insights into the historical context and interpretation of the law.

Remember, historical tax research can be complex and time-consuming. Don't hesitate to ask a law librarian or other research expert for help if you're having trouble finding or understanding historical tax materials.