Code of Federal Regulations is the codification of the general and permanent rules and regulations (sometimes called administrative law) published in the Federal Register by the Executive Departments and federal agencies of the U. S. government. The CFR is divided into 50 titles that represent broad areas subject to Federal regulation.
Congressional Research Service Reports (CRS) hosted by University of North Texas Libraries, provides full-text access to selected Congressional Research Reports which is the public policy research arm. Includes keyword and browse searching features.
Federal Register is published by the Office of the Federal Register, National Archives and Records Administration (NARA) and contains the official daily publication for rules, proposed rules, and notices of Federal agencies and organizations, as well as executive orders and other presidential documents.
FindLaw: Cases and Codes includes resources pertaining to constitutions, statutes, cases and more. Run a search for case summaries or select a jurisdiction to browse applicable laws.
IRS Tax Code, Regulations, and Official Guidance links to tax code, federal regulations, and official guidance documents.
Legalbistream offers free searchable databases of Federal tax law, including Tax Cases and IRS Materials
Tax Statistics (Statistics of Income Division) includes tables, articles, and data that describe and measure elements of the United States tax system.
United States Tax Court contains freely searchable database of Tax Court Opinions since September 25, 1995, including Memorandum opinions.