Verifying an AI-generated tax answer against primary authority

Reviewed 2026-09-15 · AI-assisted draft and editing; sources and limitations remain visible for independent review.

Answer: Treat a machine-drafted tax answer as an unverified research lead with citations attached, and run five checks in order against official sources before any of it enters your work product. Check one, existence: open the cited provision or document on an official site and confirm it exists as cited. Check two, text match: compare the quoted or paraphrased words against the official text rather than against the summary around them. Check three, currency: confirm the version you opened covers the tax period in question, a step the IRS itself flags by telling readers to check whether a Code provision displayed on a website reflects law that became effective after the year being researched. Check four, scope: confirm the subsection, paragraph and any cross-reference actually carry the proposition, since a correct section paired with the wrong paragraph is the most common defect and the hardest to see. Check five, continued validity: confirm the authority has not been overruled, reversed, revoked or superseded, because 26 CFR 1.6662-4(d)(3)(iii) provides that an authority does not continue to be an authority to the extent it is overruled or modified by a body with the power to do so. A source link in a research tool helps you reach check one faster. It does not perform checks two through five, and saying so plainly is part of using such tools responsibly.

Ask Taxterity about your own tax issue

Scope

Jurisdiction: United States — federal

Tax periods: Not period-specific; checked 2026-09-15

Assumptions

The answer under review concerns US federal tax and arrives with citations to statutes, regulations, IRS guidance or cases.
The reviewer has access to official government sources for the Code, regulations, the Internal Revenue Bulletin and court opinions.
The reviewer, not the tool, is responsible for the work product that results.

Exclusions

Evaluating or comparing particular AI research tools.
State, local and foreign tax sources.
Non-tax legal citations and non-US authority.
Any conclusion about whether a specific answer is correct.

What a source link proves, and what it does not

A link beside a sentence proves that a document was associated with that sentence. It does not prove that the document says what the sentence says, that the paragraph cited is the one that carries the point, that the version behind the link covers the reader's tax year, or that the authority is still good. Those are four separate questions, and each has a different official source that settles it.

The duty that sits behind the checks is ordinary practitioner diligence. Under 31 CFR 10.22(a)(2) and (a)(3), a practitioner must exercise due diligence in determining the correctness of oral and written representations made to the Treasury Department and of those made to clients about matters administered by the Service. Under 31 CFR 10.37(a)(2)(v), written advice must relate applicable law and authorities to the facts. Neither requirement changes because a draft arrived quickly.

Check one: does the cited authority exist as cited

Open it. Code sections live on the Office of the Law Revision Counsel site, regulations in the Code of Federal Regulations on the official government publishing site, and IRS guidance in the Internal Revenue Bulletin. The IRS page on the Code, regulations and official guidance states that the authoritative source for the distribution of all forms of official IRS tax guidance is the Internal Revenue Bulletin, and that documents not published in the Bulletin cannot be relied on, used or cited as precedents.

Failures at this check are rarely dramatic. A section number that exists but was never about the topic, a revenue procedure year that is off by one, a case name attached to a different citation: all of them read smoothly and all of them collapse on opening. Record what you opened, not what you were told.

Check two: does the quoted text match

Compare the quoted words to the official text directly, and be equally careful with a close paraphrase, which is where a qualifier tends to disappear. Words such as ordinarily, generally, except, and unless carry most of the load in tax text, and an answer that drops one has changed the rule while keeping the citation intact.

Where a source is a summary rather than the operative text, say so in your notes. An IRS overview page describing a regulation is useful for orientation and is not a substitute for the regulation, and the same applies to a form's about page relative to the form and its instructions.

Check three: is the version current for your period

Currency is a property of the version you opened, not of the citation. The IRS guidance page advises checking whether a Code provision retrieved from a website shows laws that became effective after the tax year being researched, and notes that historical editions of the United States Code back to 1994 are available electronically on GovInfo. Both official sites state their own currency in words worth reading literally. On September 15, 2026 the Office of the Law Revision Counsel page for section 6501 carried the line that its text contains those laws in effect on September 14, 2026, and the eCFR showed title 26 up to date as of 9/14/2026, last amended 9/08/2026, above a notice that eCFR content is authoritative but unofficial.

Two habits follow. Write the version into the same line as the pinpoint: the currency wording of the text you read, and the tax period your question concerns. And quote the site's own phrasing rather than a paraphrase of it, because "in effect on" a date and "up to date as of" a date are different claims, and an unofficial compilation that is current is still not the official edition. A page that is current today is not evidence about a year that closed three amendments ago.

The currency line at the top is not the whole check. Scroll to the Amendments note and the Effective Date notes at the foot of the section page, because that is where a recent change is actually disclosed. Two traps live here. First, the notes render a public-law number with an en dash, so a search typed with an ordinary hyphen returns nothing even on a section that was amended; search for the number the way the page prints it, or search the bare number and read the hits. Second, the amendment note tells you what changed but the effective-date note tells you whether it reaches your period. On the section 6501 page the 2025 entry records that Public Law 119-21 added a subsection and redesignated the former one, and the separate effective-date note says the amendment applies to taxable years beginning after July 4, 2025. An answer about an earlier year is not wrong because the section was later amended, and an answer about a later year is not right because the section text loaded.

Check four: is the subsection the right one

Read one level above and one level below the pinpoint. Above, because an exception, an effective-date rule or a definition often sits in a neighboring paragraph and reverses the reading. Below, because the proposition may depend on a subparagraph the answer never reached.

Then follow every cross-reference the cited paragraph makes. Tax provisions are built from references, and a rule that reads absolutely on its face is frequently qualified by a paragraph it points to. An answer that cites the operative sentence and ignores the reference in it has cited the right section to the wrong effect.

Redesignation is the version of this that survives every other check. When a later law inserts a subsection, the letters below it can shift, so the same lettered citation points at different text depending on the year. Section 6501 is a worked example: its amendment notes show a subsection added in 2024 with the former one redesignated, and the same thing again in 2025. A citation to a lettered subsection of that section therefore means one provision for a 2023 year and another for a 2026 year, with the section number, the letter and the quoted words all looking correct. Check the letter against the edition that governs your period, not against the current page alone.

Check five: is the authority still the law

For cases, check subsequent history. The Internal Revenue Manual states at IRM 4.10.7.2.8.7 that research of case law is not complete until the history of a case is reviewed in a citator, that a decision reversed by a higher court has no legal authority and may not be cited as precedent, and that rulings and procedures may be revoked or modified. Tax Court orders and opinions can be located through the court's DAWSON system, which offers public search of orders and opinions and a case lookup.

For administrative guidance, the operative rule is in 26 CFR 1.6662-4(d)(3)(iii): an authority does not continue to be an authority to the extent it is overruled or modified, implicitly or explicitly, by a body with the power to do so, and a private letter ruling is not authority if revoked or if inconsistent with a later proposed regulation, revenue ruling or other administrative pronouncement published in the Bulletin. The same paragraph also disposes of a frequent category error in machine-drafted answers: conclusions reached in treatises, legal periodicals, legal opinions or opinions rendered by tax professionals are not authority, however well they are written.

Record the pass, not just the conclusion

Give each proposition a verification line: document, pinpoint, version or currency date, date read, and which of the five checks it passed. Mark anything that fails as unverified and either fix it or delete it, rather than softening the sentence and keeping the citation. A softened sentence with a broken citation is harder to find later than a deleted one.

Keep the record even when everything passes. The record is what lets a colleague, or you in eight months, re-run the answer without repeating the reading, and it is the difference between a draft that happened to be right and research you can stand behind.

Honest note on tools, including this one

Taxterity answers US federal tax research questions with links to the sources behind the answer, which shortens check one and makes checks two through four possible without hunting for the document. It does not perform the verification pass for you, it does not report whether a case or ruling is still good law, and it does not decide a taxpayer's treatment.

A sensible workflow is to ask Taxterity the research question, open every linked source yourself, run the five checks, and only then move the surviving propositions into a memo. The sibling page How to structure a source-linked tax memo for a contested deduction covers the memo, and Weighing conflicting tax authorities: venue, nonacquiescence and later guidance covers what to do when two verified authorities disagree.

Related research

Official sources

IRS: Tax code, regulations and official guidance — Internal Revenue Code heading: check whether a displayed provision shows law effective after the tax year researched; historical US Code back to 1994 on GovInfo; Other official tax guidance heading on the Internal Revenue Bulletin
eCFR: 26 CFR 1.6662-4 — Substantial understatement of income tax — Section 1.6662-4(d)(3)(iii): authority ceases to the extent overruled or modified; revoked or inconsistent private letter rulings; treatises, periodicals and practitioner opinions are not authority. eCFR title 26 as of 9/14/2026
Internal Revenue Manual 4.10.7 — Issue resolution: research and law — IRM 4.10.7.2.8.7, citators and case history: research is not complete until case history is reviewed, and a reversed lower-court decision may not be cited as precedent
eCFR: 31 CFR 10.22 — Diligence as to accuracy — Section 10.22(a)(2) and (a)(3), due diligence in determining the correctness of representations made to the Treasury Department and to clients. eCFR title 31 as of 9/14/2026
eCFR: 31 CFR 10.37 — Requirements for written advice — Section 10.37(a)(2)(v), relate applicable law and authorities to facts; (a)(2)(iv) and (a)(3), unreasonable reliance on representations that are incorrect, incomplete or inconsistent. eCFR title 31 as of 9/14/2026
26 U.S.C. 6501 — Limitations on assessment and collection — Worked currency example: page states its text contains laws in effect on September 14, 2026; Amendments note 2025 (Pub. L. 119-21 added a subsection, former one redesignated) and the Effective Date of 2025 Amendment note
United States Tax Court: DAWSON — Public entry points for searching orders and opinions and for finding a case

Limitations

These five checks test citations and currency. They do not test whether the reasoning is sound, whether the right issue was identified, or whether a controlling authority was omitted entirely, which a citation check cannot detect.
No citator is described here. Confirming that a decision remains good law generally requires case-history research beyond opening the opinion itself.
The currency wording quoted here was observed on 2026-09-15 and moves: the Law Revision Counsel page stated that its text contains those laws in effect on September 14, 2026, and the eCFR showed title 26 up to date as of 9/14/2026 while describing its own content as authoritative but unofficial. Re-read both rather than relying on the dates recorded here.
The practice rules cited are professional standards for practitioners before the Service. They are used here to frame verification and are not a penalty analysis.
This page is general research information about method, not tax or legal advice, and not a statement about any particular answer or tool output.
The amendment and effective-date notes on the Office of the Law Revision Counsel site are editorial notes, not statutory text. They are reliable pointers to what changed and when, but the operative rule is the section text and the public law itself.