A quarter of the citations in filed briefs are Westlaw or Lexis ids. We list them, we do not guess.Coverage ›

Replays · S.D.N.Y. · June 22, 2023

Mata v. Avianca, Inc.

A personal injury suit against an airline, and an opposition brief that cited airline cases the court could not find. When the court asked for copies, counsel filed documents that looked like opinions. The court found that they were not, and sanctioned the two lawyers and their firm.

Court
U.S. District Court for the Southern District of New York
Decision
Opinion and Order on Sanctions, June 22, 2023 (ECF 54), 43 pages. Reported at 678 F. Supp. 3d 443.
Docket
No. 22-cv-1461 (PKC)
The filing
Plaintiff's affirmation in opposition to a motion to dismiss (ECF 21, March 1, 2023), and the copies of the cited decisions that counsel filed when the court asked for them (ECF 29, April 25, 2023).
Sanctioned
Plaintiff's two lawyers and their firm.
Sanction, in the court's words
"A penalty of $5,000 is jointly and severally imposed on Respondents and shall be paid into the Registry of this Court within 14 days of this Opinion and Order." (Opinion and Order on Sanctions, p. 34) The court also ordered letters to the client and to each judge whose name appeared on one of the copies.
AI tool, as the decision states it
"the artificial intelligence tool ChatGPT" (Opinion and Order on Sanctions, p. 1)
Public record
Opinion and Order on Sanctions, June 22, 2023 (ECF 54); Order to Show Cause, May 4, 2023 (ECF 31); Copy of "Varghese" filed with counsel's affidavit, April 25, 2023 (ECF 29-1); the case on CourtListener.

What the court found

"Technological advances are commonplace and there is nothing inherently improper about using a reliable artificial intelligence tool for assistance. But existing rules impose a gatekeeping role on attorneys to ensure the accuracy of their filings." (Opinion and Order on Sanctions, p. 1)

"Six of the submitted cases appear to be bogus judicial decisions with bogus quotes and bogus internal citations." (Order to Show Cause, p. 1)

The court found that counsel "abandoned their responsibilities when they submitted non-existent judicial opinions with fake quotes and citations created by the artificial intelligence tool ChatGPT, then continued to stand by the fake opinions after judicial orders called their existence into question." (Opinion and Order on Sanctions, p. 1)

Each citation the court listed

as filedwhat the court saidwhat the register holds at this citationour default check today
Cited in the affirmation (ECF 21)
1Varghese v. China Southern Airlines Co., Ltd., 925 F.3d 1339 (11th Cir. 2019)The Clerk of the Eleventh Circuit confirmed that the decision is not an authentic ruling of that court. (p. 10)At this citation, per the court: J.D. v Azar, 925 F.3d 1291 (D.C. Cir. 2019) (p. 11)No case at this page. The register holds this volume.Check this Not found in the register
2Shaboon v. Egyptair, 2013 IL App (1st) 111279-U (Ill. App. Ct. 2013)Named among the six decisions that, the court found, counsel acknowledged "were generated by ChatGPT and do not exist." (p. 15)No case at this page. The register holds this volume.Check this Not found in the register
3Peterson v. Iran Air, 905 F. Supp. 2d 121 (D.D.C. 2012)"The 'Petersen' decision does not exist." (p. 15)At this citation, per the court: United States v. ISS Marine Services, 905 F. Supp. 2d 121 (D.D.C. 2012) (p. 15)United States of America v. Iss Marine Services, Inc. (D.D.C. 2012)Check this Register holds a different case at this citation: United States of America v. Iss Marine Services, Inc. (2012)The brief spells the name Peterson; the copy filed later spells it Petersen.
4Martinez v. Delta Airlines, Inc., 2019 WL 4639462 (Tex. App. Sept. 25, 2019)Named among the six decisions that, the court found, counsel acknowledged "were generated by ChatGPT and do not exist." (p. 15)A Westlaw number, not a page. No open register holds these.Cannot verify Westlaw/Lexis identifier. Open registers cannot resolve it
5Estate of Durden v. KLM Royal Dutch Airlines, 2017 WL 2418825 (Ga. Ct. App. June 5, 2017)Named among the six decisions that, the court found, counsel acknowledged "were generated by ChatGPT and do not exist." (p. 15)A Westlaw number, not a page. No open register holds these.Cannot verify Westlaw/Lexis identifier. Open registers cannot resolve it
6Miller v. United Airlines, Inc., 174 F.3d 366, 371-72 (2d Cir. 1999)"The 'Miller' decision does not exist." (p. 14)At this citation, per the court: Greenleaf v. Garlock, Inc., 174 F.3d 352 (3d Cir. 1999) (p. 14)No case starts at this page. It falls inside Greenleaf v. Garlock, Inc. (3rd Cir. 1999), which starts at 174 F.3d 352.Check this Register holds a different case at this citation: Greenleaf v. Garlock, Inc. (1999)
7Zicherman v. Korean Air Lines Co., Ltd., 516 F.3d 1237, 1254 (11th Cir. 2008)"It cites to 'Zicherman v. Korean Air Lines Co., 516 F.3d 1237, 1254 (11th Cir. 2008)', which does not exist as cited." (p. 12)At this citation, per the court: Miccosukee Tribe v. United States, 516 F.3d 1235 (11th Cir. 2008) (p. 12)No case at this page. The register holds this volume.Check this Not found in the registerThe affirmation cites Zicherman, and so does the copy of "Varghese". It is listed once.
Cited inside the copy of "Varghese" that counsel filed (ECF 29-1)
8Holliday v. Atl. Capital Corp., 738 F.2d 1153 (11th Cir. 1984)"It cites to 'Holliday v. Atl. Capital Corp., 738 F.2d 1153 (11th Cir. 1984)', which does not exist." (p. 11)At this citation, per the court: Gibbs v. Maxwell House, 738 F.2d 1153 (11th Cir. 1984) (p. 11)Frank Gibbs, Jr. v. Maxwell House, a Division of General Foods Corporation (11th Cir. 1984)Check this Register holds a different case at this citation: Frank Gibbs, Jr. v. Maxwell House, a Division of General Foods Corporation (1984)
9Gen. Wire Spring Co. v. O'Neal Steel, Inc., 556 F.2d 713, 716 (5th Cir. 1977)"It cites to 'Gen. Wire Spring Co. v. O'Neal Steel, Inc., 556 F.2d 713, 716 (5th Cir. 1977)', which does not exist." (p. 12)At this citation, per the court: United States v. Clerkley, 556 F.2d 709 (4th Cir. 1977) (p. 12)No case starts at this page. It falls inside United States v. Clerkley (4th Cir. 1977), which starts at 556 F.2d 709.Check this Register holds a different case at this citation: United States v. Clerkley (1977)
10Hyatt v. N. Cent. Airlines, 92 F.3d 1074 (11th Cir. 1996)"It cites to 'Hyatt v. N. Cent. Airlines, 92 F.3d 1074 (11th Cir. 1996)', which does not exist." (p. 12)At this citation, per the court: two brief orders appearing at 92 F.3d 1074 issued by the Eleventh Circuit in other cases (p. 12)Grilli v. Metropolitan Life Insurance (11th Cir. 1996); Wyatt v. Fetner (11th Cir. 1996)Check this Register holds a different case at this citation: Wyatt Ex Rel. Rawlins v. Rogers (1996)
11Zaunbrecher v. Transocean Offshore Deepwater Drilling, Inc., 772 F.3d 1278, 1283 (11th Cir. 2014)"It cites to 'Zaunbrecher v. Transocean Offshore Deepwater Drilling, Inc., 772 F.3d 1278, 1283 (11th Cir. 2014)', which does not exist." (p. 12)At this citation, per the court: Witt v. Metropolitan Life Ins. Co., 772 F.3d 1269 (11th Cir. 2014) (p. 12)No case starts at this page. It falls inside Don L. Witt v. Metropolitan Life Insurance Co. (11th Cir. 2014), which starts at 772 F.3d 1269.Check this Register holds a different case at this citation: Don L. Witt v. Metropolitan Life Insurance Co. (2014)
12In re BDC 56 LLC, 330 B.R. 466, 471 (Bankr. D.N.H. 2005)"It cites to 'In re BDC 56 LLC, 330 B.R. 466, 471 (Bankr. D.N.H. 2005)', which does not exist as cited." (p. 12)At this citation, per the court: In re 652 West 160th LLC, 330 B.R. 455 (Bankr. S.D.N.Y. 2005) (p. 13)No case starts at this page. It falls inside In Re 652 West 160th LLC. (Bankr. S.D.N.Y. 2005), which starts at 330 B.R. 455.Cannot verify Pin page 471 is outside the opinion. Check the pageThe citation points inside the opinion; the register places the case at 330 B.R. 455.The page falls inside In re 652 West 160th LLC, and the name check skips captions that begin with "In re", so the mismatch itself goes unflagged. The row still lands in the review queue: pin page 471 lies past the end of that opinion, and the check marks it orange. The row names the case it found, so the difference shows.
Real cases the "Varghese" copy cited for points the court says they do not makeThe court gives these in its own words, with correct names and citations. Our default check confirms that a case sits at the citation under that name. It does not read whether the case says what it was cited for, so a real case comes back Found. The opt-in deep check reads the passage; it was not run for this page.
13In re Rimstat, Ltd., 212 F.3d 1039 (7th Cir. 2000)In re Rimstat "is a decision relating to Rule 11 sanctions for attorney misconduct and does not discuss the federal bankruptcy stay." (p. 13)In Re: Rimsat, Limited, Debtor, Appeals Of: Kauthar Sdn Bhd (7th Cir. 2000)Found Found: In Re: Rimsat, Limited, Debtor, Appeals Of: Kauthar Sdn Bhd (7th Cir. 2000)
14In re PPI Enterprises (U.S.), Inc., 324 F.3d 197 (3d Cir. 2003)In re PPI Enterprises "does not discuss the federal bankruptcy stay, and is incorrectly identified as an opinion of the Second Circuit." (p. 13)Solow v. PPI Enterprises (U.S.), Inc. (3rd Cir. 2003); In Re Ppi Enterprises (3rd Cir. 2003)Found Found: In Re Ppi Enterprises (3rd Cir. 2003)
15Begier v. I.R.S., 496 U.S. 53 (1990)Begier "does not discuss the federal bankruptcy stay, and addresses whether a trustee in bankruptcy may recover certain payments made by the debtor to the Internal Revenue Service." (p. 13)Begier v. Internal Revenue Service (U.S. 1990)Found Found: Begier v. Internal Revenue Service (U.S. 1990)
16Kaiser Steel Corp. v. W. S. Ranch Co., 391 U.S. 593 (1968) (per curiam)Kaiser Steel "does not discuss the federal bankruptcy stay, and held that a federal proceeding should have been stayed pending the outcome of New Mexico state court proceedings relating to the interpretation of the state constitution." (p. 13)Kaiser Steel Corp. v. W. S. Ranch Co. (U.S. 1968)Found Found: Kaiser Steel Corp. v. W. S. Ranch Co. (U.S. 1968)
17El Al Israel Airlines, Ltd. v. Tsui Yuan Tseng, 525 U.S. 155, 161 (1999)Quoted in the filing: "modernize and unify the Warsaw Convention system by establishing new and uniform rules governing the international carriage of persons, baggage, and cargo." (Copy of "Varghese" filed with counsel's affidavit, p. 6)El Al "does not contain the quoted language discussing the purpose of the Montreal Convention." (p. 13)El Al Israel Airlines, Ltd. v. Tsui Yuan Tseng (U.S. 1999)Check this Quoted language not in the opinion
18In re Gandy, 299 F.3d 489 (5th Cir. 2002)In re Gandy "affirmed a bankruptcy court's denial of a motion to compel arbitration." (p. 13)In re Gandy (5th Cir. 2002)Found Found: In re Gandy (5th Cir. 2002)

18 citations. Run September 24, 2026 with the default check, engine 0.5.0, register data of June 30, 2026: 10 Check this, 3 Cannot verify, 5 Found. Each citation was pasted as a line of text (the quoted words first, where we have them) and checked the way the checker checks a draft: no language model, nothing stored. The register column is a direct lookup of the volume and page.

What a check before filing would have shown

Pasted before filing, the affirmation's seven citations would have come back as five "Check this" rows (each one naming the case the register holds at that page, or saying no case starts there) and two Westlaw numbers to pull by hand.

What this page does not show

  • The court itemized the citations inside only the three copies that purported to be federal decisions. It says the Shaboon, Martinez and Durden copies "contain similar deficiencies" (p. 15) without listing them, so they are not in the table.
  • The court also ordered copies of Ehrlich v. American Airlines and In re Air Crash Disaster Near New Orleans. It does not list either as a problem, so neither is in the table.
  • The El Al quotation is taken from the copy of "Varghese" that counsel filed (ECF 29-1, p. 6), because the opinion does not reproduce it.
  • Whether a case is still good law. This is not a citator.
  • Anything about the lawyers beyond what the court wrote.

Check your own draft

Paste the draft or upload the PDF. The default check reads every case citation and returns rows like the ones above in a few seconds, with no language model and nothing stored. It is free to try without an account. Then read what the court would read: every case you cite, at the page you cite.

Check a draft before you fileAll replays

Published September 24, 2026, updated September 24, 2026. We read the decision and copied the court's list; if we have misread it, write to hello@proofread.law. The rows are from the run dated above; they can change when the checker does.