Tax Research: Understanding Sources of Tax Law (Why my IRC beats your Rev Proc!)

Courtesy of Wolters Kluwer CCH.

How do tax sources rank in terms of authority? Check out "Tax Research: Understanding Sources of Tax Law (Why my IRC beats your Rev Proc!)." You can access the PDF document here.

In terms of authority, the order from highest on down appears to be as follows:

1. U.S. Constitution
2. Internal Revenue Code 
3. Treasury Regulations
4. Legislative History
5. Judicial Authority
   (a) U.S. Supreme Court (binding on all lower federal courts)
   (b) U.S. Court of Appeal (binding on district courts within same circuit, but highly persuasive for other federal circuit courts of appeal)
   (c) U.S. Tax Court (regular decisions can be cited as precedent; memorandum opinions have less authority, but can also be cited as precedent; summary decisions are persuasive, but have no precedential value)
   (d) U.S. Court of Federal Claims (precedential value in Court of Federal Claims and Court of Appeals for the Federal Circuit)
   (e) U.S. District Court (not binding on any courts, but may be persuasive)
6. Revenue Rulings
7. Revenue Procedures