Tax Research, Authority Hierarchy, and Professional Responsibilities
What this domain tests
This domain tests whether you can identify controlling authority for a fact pattern, rank sources by weight, and apply the professional standards that govern practice before the IRS. Questions often ask which citation is strongest, whether a position has substantial authority, and what a preparer must do when a client refuses to correct an error.
Authority hierarchy
Primary authority is the law itself; secondary authority such as treatises, articles, and IRS publications only helps locate primary authority. Within primary authority:
- Statutory: the Internal Revenue Code. Committee reports are legislative history; they are persuasive but not binding.
- Administrative: final Treasury regulations issued under IRC §7805 are the IRS’s authoritative interpretation and are generally followed by courts; proposed regulations are not binding and cannot be relied on for penalty protection. Revenue rulings state the IRS position in a given fact pattern but do not bind courts; revenue procedures state internal management. Private letter rulings bind only the taxpayer who requested them; TAMs and CCAs are internal guidance.
- Judicial: Supreme Court decisions bind all; a circuit court of appeals binds district courts and the Tax Court within that circuit under the Golsen rule. Regular Tax Court opinions are precedential; memorandum opinions are not. District Court and Court of Federal Claims decisions are persuasive outside their circuits.
Research method and professional duties
Frame the facts, state the issue, locate authority, evaluate weight and validity, then conclude. Use a citator to confirm that a case or ruling has not been reversed, superseded, or obsoleted. Under Circular 230 §10.22, a practitioner must exercise due diligence in preparing returns and advising clients; §10.21 requires advising the client about an omission but not disclosing it without consent. §10.34 prohibits frivolous positions and requires substantial authority for undisclosed positions, reasonable basis with disclosure, and more likely than not for tax shelters. Preparer penalty §6694 mirrors these standards.
Worked example
A client wants to deduct a home office used partly for personal purposes. You find IRC §280A, a final regulation, a regular Tax Court opinion favorable in the Ninth Circuit, and a memorandum opinion contrary in the Fifth Circuit. If the client resides and files in the Ninth Circuit, the Tax Court would follow the Ninth Circuit under Golsen. The regular opinion is stronger than the memo, but §280A and the regulation control if they conflict with the case. Advice should rest on the statute and regulation first, then the favorable circuit precedent.
Traps
- Citing IRS Publications as authority.
- Treating a PLR as precedent for another taxpayer.
- Ignoring the Golsen rule or the difference between regular and memorandum Tax Court opinions.
- Relying on proposed regulations or an outdated ruling without citator review.
- Confusing “substantial authority” with “more likely than not.”