ChatGPT Plus on Loper Bright's Superficial Claim of Court's Ability to Determine a Single Best Reading in State of Ambiguity (9/24/26; 9/25/26)

In my recent article, John A. Townsend, Loper Bright Flip Flops on Chevron Deference: A Tax Lawyer's Perspective, 79 Tax Law. 323 (2026), on SSRN here, I critiqued the Court’s opinion in Loper Bright Enterprises v. Raimondo, 603 U.S. 369 (2024) (C.J. Roberts), here [Preliminary Print]. One of the points I made was that the Court’s claim that “statutes, no matter how impenetrable, do— in fact, must—have a single, best meaning.” (603 U.S., at 400.) The Court also claimed that courts could and must discern that single best meaning without a default rule to decide the case—such as Chevron and, presumably, some substantive canons that require ambiguity. In Loper Bright’s sweeping claims, no room seemed to be left for statutory ambiguity. However, statutory ambiguity was a common phenomenon before Loper Bright; Loper Bright cannot by fiat eliminate statutory ambiguity.

Added 9/24/26 8:00pm: In my Federal Tax Procedure Book 2026 (Practitioner Ed. p. 91; Student Ed. p. 58) this issue is the first issue I raise about Loper Bright:

1. What does a court do when, after it applies Loper Bright’s exhortations to determine the “best” interpretation, the court still finds statutory ambiguity (interpretive equipoise)? Ambiguity (interpretive equipoise) existed before Loper Bright and exists after Loper Bright. Remember the lesson of lenity–ambiguity (interpretive equipoise) requires a default rule to resolve the case.

I decided to use ChatGPT Plus to further explore the phenomenon of statutory ambiguity. That AI tool gave surprisingly cogent answers and step by step reasoning that highlight the lapse in logic of Loper Bright. I wish I had the responses in preparing the article cited above. I offer below the last two prompts and response (after refining earlier prompts and responses). I have left the bold-face and italics as ChatGPT had them; also, ChatGPT sometimes refers to Loper Bright as Loper and does not italicize Loper or Chevron. I have not changed that. Remember these are the final prompts and responses after earlier prompts drilled down to these final two prompt. Those interested in seeing the entire discussion with ChatGPT Plus may do so here.

I am impressed with how ChatGPT responds in an analytically meaningful way to step through  the issues and reach its conclusions. To readers interested in this stuff, ENJOY!

Two points about the Responses: 

1. The first response below refers to my article above without citing the article or otherwise attributing it to me. See par. 4 below. I do not know if ChatGPT Plus recognized that the article that it cited was written by the person with whom it was "chatting." I infer that it did not recognize me as the author of the article.
2. The first response (par. 5) refers to the Flight Options case which it discussed in earlier responses and which I discuss in Interesting Concurring Opinion on Canons (or Maxims) of Statutory Interpretation (Federal Tax Procedure Blog 5/29/26; 8/21/26), here.

JAT Prompt #1: 

In the foregoing discussion, you used 50-50 as the state of interpretive equipoise. Can interpretive equipoise be encountered in a range--say of 45-50 or even 40-60. (These numbers are in percentages.)

ChatGPT Response to Prompt # 1:

Yes—but I would refine the terminology. Interpretive equipoise need not mean a mathematically exact 50–50 tie. It can sensibly describe a zone of interpretive uncertainty within which a court cannot determine, with sufficient confidence, that one interpretation is genuinely “better” than the other. There is, however, no judicially established numerical range such as 45–55 or 40–60.

That distinction becomes important under Loper Bright.

District Court Sustains IRS Summons at Treaty Partner's Request, Requesting Third-Party Contact Requirement (9/19/26)

In United States v. Yoon (N.D. Cal. No.26-cv-01423-VC  Order dtd 9/17/26 at # 34), CL here and GS here, the Court enforced an IRS summons issued in response to a request by a treaty partner, South Korea. The significant issues addressed are:

1. The Government need only satisfy the four-part Powell test. United States v. Powell, 379 U.S. 48, 57–58 (1964). (Slip Op. 3.)

2 In applying Powell, only the IRS’s good faith is in issue, not the treaty partner’s good faith. Id.

3 Relevance of the summons to a legitimate tax investigation of the treaty partner is not in issue. (Slip Op. 4-5.) South Korea’s request to the IRS “said that all that information was relevant, and it only sought records from the years that match its investigation;” the “request seems sensible on its face.” There is no requirement that the IRS go behind the treaty partner’s statement of relevance.

4. The Court rejected Yoon’s argument that § 7602(c) requires 45-day notice which was not given here. (Slip Op. 5-7.) The notice period, although stated without limitation in the statutory text, is properly read in context not to apply to a summons issued at a treaty partner’s request. The Court concluded (Slip Op. 7) that “there is no ambiguity” as to that reading of the statute.

5. With regard to this interpretation of the statute, the Court acknowledged the IRS’s long-time consistent interpretation to that effect in Regulation § 301.7602-2(c)(3)(C), noting that the interpretation might in a state of ambiguity be useful in statutory interpretation (absent here), this consideration (Slip Op. 7-8):

          For what it’s worth, another consideration works against Yoon here: the IRS’s own longstanding interpretation that section 7602(c) does not apply to foreign tax liabilities. 66 Fed. Reg. 77 (Jan. 2, 2001) (codified at 26 C.F.R. § 301.7602-2(c)(3)(C)). After considering the ordinary meaning of statutory language, a court may look to the interpretation of the agency responsible for implementing the statute. Leon-Vriviesca, 179 F.4th at 1191. Such agency interpretations receive “‘due respect,’ but not binding deference.” Lopez v. Garland, 116 F.4th 1032, 1039 (9th Cir. 2024) (quoting Loper Bright Enterprises v. Raimondo, 603 U.S. 369, 403 (2024)). The IRS’s regulation was issued in 2001, just a few years after the codification of section 7602(c) in 1998, and has remained consistent since then. Therefore, even if the statutory text were ambiguous, the IRS’s interpretation would be “especially useful in determining the statute’s meaning”—and that might cut against Yoon’s legislative purpose argument. Loper Bright, 603 U.S. at 394 (citing Skidmore v. Swift & Co., 323 U.S. 134, 140 (1944)).n5
   n5 The government makes an alternative argument that the general grant of rulemaking authority to the IRS in 26 U.S.C. § 7805(a) empowers the agency to “fill up details” in the statutory scheme; i.e., that section 7805(a) explicitly authorizes the agency to define the phrase “tax liability” in section 7602(c). But the best reading of the statutory text, informed by due respect to the IRS’s regulation, is that section 7602(c) does not apply to foreign tax liabilities. It is therefore not necessary to consider whether section 7805(a) can bear the weight that the government says it does.

JAT Comment:

District Court Sustains IRS Summons at Treaty Partner's Request, Requesting Third-Party Contact Requirement (9/19/26)

In United States v. Yoon (N.D. Cal. No.26-cv-01423-VC  Order dtd 9/17/26 at # 34), CL here and GS here [to come], the Court enforced an IRS summons issued in response to a request by a treaty partner, South Korea. The significant issues addressed are:

1. The Government need only satisfy the four-part Powell test. United States v. Powell, 379 U.S. 48, 57–58 (1964). (Slip Op. 3.)

2. In applying Powell, only the IRS’s good faith is in issue, not the treaty partner’s good faith. Id.

3. Relevance of the summons to a legitimate tax investigation of the treaty partner is not in issue. (Slip Op. 4-5.) South Korea’s request to the IRS “said that all that information was relevant, and it only sought records from the years that match its investigation;” the “request seems sensible on its face.” There is no requirement to test the treaty partner’s statement of relevance.

4. The Court rejected Yoon’s argument that § 7602(c) requires 45-day notice which was not given here. (Slip Op. 5-7.) The notice period, although stated without limitation in the statutory text, is properly read in context not to apply to a summons issued at a treaty partner’s request. The Court concluded (Slip Op. 7) that “there is no ambiguity” as to that reading of the statute.

5. With regard to this interpretation of the statute, the Court acknowledged the IRS’s long-time consistent interpretation to that effect in Regulation § 301.7602-2(c)(3)(C), noting that the interpretation might in a state of ambiguity be useful in statutory interpretation (absent here), this consideration (Slip Op. 7-8): 

          For what it’s worth, another consideration works against Yoon here: the IRS’s own longstanding interpretation that section 7602(c) does not apply to foreign tax liabilities. 66 Fed. Reg. 77 (Jan. 2, 2001) (codified at 26 C.F.R. § 301.7602-2(c)(3)(C)). After considering the ordinary meaning of statutory language, a court may look to the interpretation of the agency responsible for implementing the statute. Leon-Vriviesca, 179 F.4th at 1191. Such agency interpretations receive “‘due respect,’ but not binding deference.” Lopez v. Garland, 116 F.4th 1032, 1039 (9th Cir. 2024) (quoting Loper Bright Enterprises v. Raimondo, 603 U.S. 369, 403 (2024)). The IRS’s regulation was issued in 2001, just a few years after the codification of section 7602(c) in 1998, and has remained consistent since then. Therefore, even if the statutory text were ambiguous, the IRS’s interpretation would be “especially useful in determining the statute’s meaning”—and that might cut against Yoon’s legislative purpose argument. Loper Bright, 603 U.S. at 394 (citing Skidmore v. Swift & Co., 323 U.S. 134, 140 (1944)).n5
   n5 The government makes an alternative argument that the general grant of rulemaking authority to the IRS in 26 U.S.C. § 7805(a) empowers the agency to “fill up details” in the statutory scheme; i.e., that section 7805(a) explicitly authorizes the agency to define the phrase “tax liability” in section 7602(c). But the best reading of the statutory text, informed by due respect to the IRS’s regulation, is that section 7602(c) does not apply to foreign tax liabilities. It is therefore not necessary to consider whether section 7805(a) can bear the weight that the government says it does.

 JAT Comments:

D.C. District Court Rejects Tax Analyst's FOIA Request For Background File on TAM That Might Identify Taxpayer Among the Taxpayers that Littlejohn Disclosed (9/18/26)

In Tax Analysts v. IRS (D.D.C. No. 1:24-cv-03257 at # 32 Memo Opinion & Order dtd 9/9/26) CL here, Tax Analysts sought disclosure of the background file for Technical Advice Memorandum TAM 201929019, TN here, on basis shifting strategy. In its order, the Court did not identify the TAM, but the TAM is identified in the Complaint here, Answer here, and Government  Motion for Summary Judgment here. The Court’s order is short, so I just quote it:

          The parties have agreed that this case can easily be resolved once the identity of the subject taxpayer is known. See Pl. Resp. at 1; Reply at 1. Plaintiff does not have this information and, for reasons to be explained, the IRS refuses to make it available to the plaintiff. Instead, the parties agree that the case could move forward if this Court reviewed the disputed material in camera. See Pl. Resp. at 2; Reply at 1-2. At the Court's request, the IRS delivered the relevant materials to the Court on September 4, 2026, and the Court has now reviewed them.

          The parties agree that former IRS contractor Charles Littlejohn publicly disclosed tax return information of "some prominent Americans," including Donald Trump, Warren Buffett, Bill Gates, Rupert Murdoch, Mark Zuckerberg, Jeff Bezos, Elon Musk, and others. The parties now also agree that if the taxpayer here is a person of such prominence, he or she could easily be identified with the Littlejohn disclosure and related news reporting. See Pl. Resp. at 2; Reply at 1-2.Any member of the public would be able to identify the subject taxpayer. If that is the case, the parties agree, the Court necessarily would conclude that the withheld documents are exempt from disclosure. See id. (citing 26 U.S.C. §6110(c)(1) and (c)(5)). The Court, having now reviewed the documents in camera, concludes that the subject is a person of such prominence that disclosure would be tantamount to identifying the taxpayer. Therefore, the records may be withheld. Accordingly, it is hereby

          ORDERED that on or before September 23,2026, the parties shall meet and confer and file a joint status report suggesting appropriate next steps in this case.

As presented, the Memo and Order raises the question as to which taxpayer the TAM relates to—"Donald Trump, Warren Buffett, Bill Gates, Rupert Murdoch, Mark Zuckerberg, Jeff Bezos, Elon Musk, and others.”

Second Circuit Affirms the Tax Court in Holding Limited Partners Must Really Be Limited Partners (9/17/26)

In Soroban Capital Partners LP v. Commissioner, ___ F.4th ___ (2d Cir. 9/17/26), CA2 here, CL here, and GS here, the Panel (Judges Calebresi, Chin , and Merriam, with opinion by Chin) affirmed the Tax Court’s decision holding that persons nominated as limited partners who exercised managerial control did not qualify for the limited partner exception to the Medicare tax. Specifically, the opinion states its holding (Slip Op. 30):

We hold that "limited partner," as used in § 1402(a)(13), means a partner who, in addition to having limited liability, does not run, manage, or control the partnership's business.10 We arrive at this conclusion based on three sources that provide guidance as to the meaning of the term as used here: (1) the text of the statute and its ordinary meaning in 1977, when § 1402(a)(13) was enacted; (2) the statute's surrounding text and structure; and (3) the statute's legislative history and historical context.

This is a major opinion simply because the scam it shoots down was so egregious. I don’t feel that I can add anything meaningful to the substantive opinion. To the extent readers may be interested in my opinion, I think it is correct. I will make some comments that, like many of my blogs, will address picky issues in the opinion.

JAT Comments:

Tax Court Deploys Interpretive Tools to Resolve Complex Transaction/Scheme to Exploit Statutory Glitch (9/17/26)

In Sysco Corp. v. Commissioner, T.C. Memo. 2026-84, TC here at # 108 dtd 9/14/26 & GS here, the Court rejects Sysco’s attempts to avoid the result of prior T.C. decisions resolving the issue in Sysco. Varian Medical Systems, Inc. & Subs. v. Commissioner (Varian I), 163 T.C. 76 (2024) (reviewed), and Varian Medical Systems, Inc. & Subs. v. Commissioner (Varian II), No. 8435- 23, 166 T.C. (Apr. 8, 2026).

In this blog, I do not address the substantive issue that the parties fussed about. Rather, I address the tools of statutory interpretation the Court claimed to deploy in resolving the interpretive issue.

My basic theory of statutory interpretation is that it is in many ways similar to factfinding—it is lawfinding. In factfinding, relevant evidence generally should be considered for what it is worth. See FRE 401 and 402. So, too, in statutory interpretation relevant evidence as to the meaning of the statutory text should be considered for what it is worth. My main beef in the current statutory interpretation milieu is the notion that interpreters should categorically reject legislative history (other than statutory history). 

Let’s walk through how the court deploys the tools of statutory interpretation:

1. the Court “begin[s] with the [statutory] text.” (*7.) I fully agree with that and cannot imagine anyone who would disagree. Indeed, on this point, I agree with Justice Kagan’s famous statement that “We’re all textualists now.)

2. Immediately after stating the obvious starting point (#1), the Court jumps into quicksand: “when the statute does not define a term, “we ask what that term’s ‘ordinary, contemporary, common meaning’ was when Congress enacted” the relevant text. The court correctly cites cases that do stand for the proposition and, I suppose, the proposition is correct, provided that there is more nuance. How does one determine the statutory term’s “ordinary, contemporary, common meaning” relevant to its meaning in a complex tax statute?

Tax Court on Murky Facts Affirms Deficiency on Net Amount Taxpayer Retained from Flow of Funds (9/15/26)

In Tunkl v. Commissioner, T.C. Memo. 2026-83, Tunkl was an art dealer for the wealthy (at least some of the wealthy). He managed to arrange a flow of funds from one other wealthy art dealer, initially to finance his acquisition for a particular painting but not actually used for the painting. The precise nature of that flow of funds is murky because people in such wealthy circles in art may not fully document flows of funds, but when the smoke cleared Tunkl ended up with $16.5 million net. The IRS determined a deficiency for tax on that amount. (I did not read closely enough to determine whether the deficiency asserted the tax to Tunkl directly or through his subchapter S corporation; the bottom-line is that the deficiency was Tunkl’s in either event.)

In getting past the murkiness in the facts, the Court concluded (*10).

          Finally, and most importantly, Mr. Tunkl has been permitted to keep the entire amount he received from Mr. Mnuchin. Mr. Tunkl repaid only $2.5 million of the total $44 million owed to Mr. Mnuchin. Pursuant to the Addendum, the $16.5 million owed from the Picasso painting deal was severed from the Note into its own smaller note. Mr. Tunkl has provided no evidence demonstrating that the $2.5 million was partial repayment of this smaller note. Therefore, Mr. Tunkl has failed to demonstrate that he was not permitted to keep the entire $16.5 million.

JAT Comments:

1. It seems to me that taxing the net benefit to Tunkl is the right answer. My only thought/concern was that, given the murkiness in the facts, it is at least possible that the income may not have arisen in 2018 the year for which the notice of deficiency was issued. I suppose, however, that if Tunkl had fought the timing battle, he may have still lost for the tax via the mitigation provisions of the Code, but possibly might have achieved an interest benefit if a later year were the proper year.

D.C. District Court Case Dismisses Refund Suit Where IRS Made an Allegedly Erroneous Refund and Transfers the Government's Erroneous Refund Suit to Another Venue (9/15/26)

In Fuentes v. United States (D. D.C. 9/4/26), CL here and GS here, Fuentes was a foreign resident with no U.S. residence at all relevant times. He brought a refund suit in the Western District of Texas. After finding proper venue in the D.C. District Court, the refund suit was moved to the D.C. District Court. At some point, the IRS refunded the tax that was the basis of the refund suit. The United States then moved by counterclaim to seek recovery of the refunds allegedly erroneously made. Fuentes then moved to dismiss his refund suit. The Government moved to transfer the erroneous refund suit to the Western District of Texas finding that, although the Government could have brought the erroneous in other venues, the Western District of Texas was the most appropriate venue (see point # 4 below).

I point out some aspects of the opinion I found interesting:

1. The amount sought in the refund suit was for penalties paid after the IRS assessed the Form 3520 penalties.

2. As noted, the IRS refunded the tax in issue. The Government argued that the reason the refund was erroneous is that the refund case had been referred to DOJ which should have legally prohibited the IRS from making the refund. This is because the original referral gave DOJ exclusive authority to settle the liability. § 7122(a). Of course, the issue of whether the refund was erroneous will be litigated in the transferred venue.

3. Fuentes argued that the IRS, presumably intentionally, made the refund and its determination should mean that the refund and its predicate abatement were not erroneous, invoking the standard notion that the client (DOJ’s client, the IRS) should control this type of decision and that the IRS’s decision should be given collateral estoppel effect making the refund and abatement issue “prudentially moot.” (Slip Op. 7 & 14-15.) The Court rejected those arguments.

ChatGPT on Picking Evidence in Statutory (and Constitutional) Interpretation (9/13/26)

Today, I was reworking the part of my 2027 Working Draft for my Federal Tax Procedure Editions on the problem of cherry-picking or selecting evidence used in constitutional and statutory interpretation. The issue is presented anecdotally by conservative judges trotting out Judge Leventhal’s famous remark that using legislative history is like looking over the crowd and picking your friends. There is a similar phenomenon with so-called “law office history” deployed to support arguments made by advocates and judges in their opinions. Even broader, the same phenomenon is presented for the entire body of law that advocates and judges deploy—such as cases, scholarly treatises, law review articles, etc. The risk is always present that we as lawyers (or judges) pick our friends rather than make a neutral assessment of the evidence.

Continuing my experimentation with AI, I asked ChatGPT Plus about the issue and got what I think are pretty good responses. I presented the issue in two prompts (the second asking for more than the first) noted below in red. The bold face was from the original responses. I checked the citations to the two Supreme Court cases and they are correct (i.e., no hallucinations). I will use the responses in re-working my discussion in the Federal Tax Procedure Editions (not verbatim but to inspire how I state the concepts in my own words which I hope are at least as good as ChatGPT's).

As an introduction, I use the term "law office history." That term commonly describes the phenomenon of lawyers and judges evaluating history as a process of cherry-picking to support arguments. Of course, selecting the evidence is what we all do when making arguments or taking positions; lawyers do that in briefs and oral arguments; judges do that in opinions; we all do that in our daily discourse. Even when a person--say a judge--sees his or her duty to make an objective or fair assessment of the evidence, personal prejudices or preferences may influence the evidence used. I wanted to explore what that may mean.

One caveat: The same phenomenon occurs in factfinding where a judge selects from a body of factual evidence the evidence that he or she finds persuasive to determine facts relevant to the outcome of the case. I don't think factfinding is materially different from lawfinding--selecting among the relevant evidence to reach the outcome.

Prompt #1

Please write a short discussion of the features of "law office history" and "legislative history" that permit a judge or lawyer to cherry pick (or as one judge called it to look over a crowd and pick your friends).

Response to Prompt #1

Here is a short version in a law-review style that emphasizes the structural similarity between the two problems:

Law-Office History and Legislative History

Both “law-office history” and legislative history present a similar danger: they often supply the interpreter with a large and heterogeneous body of material from which supporting evidence can be selected without any obvious neutral rule for determining what evidence should receive the greatest weight. Alfred H. Kelly coined “law-office history” to describe the lawyerly practice of selecting historical data favorable to a position while failing adequately to confront contrary evidence or evaluate its significance in historical context. The problem is partly inherent in advocacy. The historical record is usually extensive, incomplete, and capable of supporting competing narratives; choices must be made about the relevant period, the appropriate level of generality, which practices are representative, and which sources deserve weight. Those choices can permit the advocate—or judge—to begin with a desired conclusion and assemble a plausible historical narrative supporting it.

Legislative history presents much the same problem, perhaps in an even more concentrated form. A statute may generate committee reports, sponsor statements, floor debates, hearing testimony, rejected amendments, conference materials, and statements by legislators who supported or opposed the final bill. These materials may point in different directions, and statements by particular legislators do not necessarily represent the understanding of the legislative body that enacted the statute. Moreover, participants aware that courts consult legislative history may have incentives to place favorable statements in the record. The resulting abundance of potentially conflicting material makes selective quotation unusually easy. The Supreme Court has accordingly repeated Judge Harold Leventhal's famous description of using legislative history as akin to “looking over a crowd and picking out your friends.” Exxon Mobil Corp. v. Allapattah Services, Inc., 545 U.S. 546, 568 (2005).

Judge Holmes Decides on Burden of Proof (Persuasion) (9/3/26)

In Risan v. Commissioner, T.C. Memo. 2026-78, TC here at #93, TN here, and GS here [to come], Judge Holmes decided significant factual issues on burden of proof. The key reason I thought this case interesting is that Tax Court Judges often, after noising about burden of proof, will just hold that, in effect, burden of proof is irrelevant to the outcome because the Judge in the particular case has resolved those factual issues by a preponderance of the evidence. That is simply to say that, in the normal case where the preponderance of the evidence standard applies, burden of proof is relevant only if the Judge is in factual equipoise unable to determine whether or not a critical fact is more likely than not. In that state of equipoise, the party with the burden of persuasion loses.

Judge Holmes sets up the discussion at the beginning of the Opinion section (starting at *17, footnote omitted):

          We begin with a number of issues for which Mr. Risan presented no evidence or argument, or about which he included only an underdeveloped argument in his brief. Taxpayers usually bear the burden of proof in cases before us. Rule 142(a). The Code does sometimes shift this burden to the Commissioner. See § 7491(a). But when neither party presented evidence in these cases, we simply find that Mr. Risan did not comply with the Code’s recordkeeping requirements and did not cooperate with the Commissioner’s reasonable requests for information. This means that, for a great many issues, we find against Mr. Risan and for the Commissioner.

 Other JAT comments:

1. Judge Holmes also addressed the statute of limitations. Judge Holmes found (i) there was a 25% omission in the years involved invoking the six-year statute of limitations and (ii) for some of the years during the six-year period, the taxpayer timely signed consents to extend. Judge Holmes said that, although the taxpayer testified that he did not sign the forms, visual review of the forms permitted him to “find it more likely than not that he did sign them.” (*19.) Although Judge Holmes did not say it directly, that finding means that it is more like than not that the taxpayer testified untruthfully (whether or not the taxpayer intended to deceive is a different issue).