Stephen McCarthy v. DEA

                                     PRECEDENTIAL

    UNITED STATES COURT OF APPEALS
         FOR THE THIRD CIRCUIT
              ____________

                   No. 24-2704
                  ____________

          STEPHEN MCCARTHY, P.A.,
                             Petitioner

                         v.

   UNITED STATES DRUG ENFORCEMENT
            ADMINISTRATION
              ____________

            On Petition for Review of an
   Order of the Drug Enforcement Administration
                (Agency No. 23-40)
                   ____________

 Submitted Pursuant to Third Circuit L.A.R. 34.1(a)
                  May 20, 2025
                 ____________

Before: PHIPPS, CHUNG, and ROTH, Circuit Judges

              (Filed: March 27, 2026)
                        ____________

                 OPINION OF THE COURT
                      ____________

CHUNG, Circuit Judge.

        An attorney submitted a brief to this Court which
contained legal authority summarized and provided to him by
a non-attorney. The attorney failed to verify the legal authority
in any way. Unfortunately, the research contained myriad
inaccuracies. Even after learning of the inaccuracies, the
attorney neither read nor verified the existence of the
authorities and, nonetheless, submitted another brief casting
the mistakes as “immaterial.” Reply Br. 14. After submitting
both briefs, the attorney confirmed his suspicion that the
erroneous citations were generated by AI. Even so, he still
neither read nor verified the existence of the cited authorities.
To the contrary, the attorney made no attempt to remediate the
situation until we ordered him to provide copies of the cited
authorities and explain if or how he verified their accuracy. We
conclude that this course of conduct violated this Court’s rules
and will impose sanctions.

I.     BACKGROUND

       Daniel A. Pallen, Esq. (“Attorney”) represented the
Appellant in McCarthy v. United States Drug Enforcement
Administration, No. 24-2704. He is an attorney admitted to the
bar of this Court and the Pennsylvania bar. See McCarthy v.
U.S. Drug Enforcement Admin., No. 24-2704 2025 WL
2028399 (3d Cir. July 21, 2025). On September 30, 2024,
Attorney filed the Opening Brief in that case. To support his
argument that the Drug Enforcement Agency (“DEA”) acted




                                   2
inconsistently with its prior practice, he provided summaries of
eight DEA adjudications. We now know that in including and
preparing these summaries, Attorney relied on case overviews
generated by AI and provided to him by a non-attorney.
Attorney “modified some of the [provided] language for ease
of reading and then simply incorporated the same into the
brief” without verifying the existence or accuracy of the
citations. He then submitted the brief under his signature as an
officer of the court. The summaries for seven of the authorities
were riddled with factual and legal inaccuracies, and one of the
authorities simply did not exist. In its Response Brief, the
Government catalogued these failures. Despite reading the
response, Attorney did not check the citations.

        Attorney then began preparing the Reply Brief. He still
did not check the citations, even while suspecting that AI had
been used by the non-attorney in providing suggestions to
Attorney for both the Opening Brief and the Reply Brief. 1
Attorney filed the Reply Brief on February 6, 2025. In that
brief and, again, having never checked the citations, he stated
that the erroneous citations were part of “a good faith effort to
chronicle Agency disparities, [and that there were] some
immaterial misstatements about the cited cases’ tangential
details.” Reply Br. 14. He further characterized the



1
       At the beginning of the show cause hearing, we
reminded Attorney of his obligation of confidentiality to his
client before he spoke or answered questions.            See
Pennsylvania Rules of Professional Conduct 1.6. In coming to
our decision here, we need not rely on any communications he
had with his client and will not refer to them.




                                   3
inaccuracies within the summaries and the non-existence of a
cited adjudication as “minor discrepancies.” Id.

        Attorney states that “[i]t was not until a few days later
in mid-February 2025” that he “conclusively deduced that the
citations and case descriptions made in the Opening Brief” had
been generated by AI. ECF 56, Corrected Response to Order
to Show Cause Dated July 21, 2025 (“Resp. to OSC”) 3. Upon
realizing this, Attorney took no action whatsoever.

       On May 15, 2025, this Court ordered Attorney to
provide copies of the eight adjudications summarized in the
Opening Brief. It was at this point that Attorney finally
checked the authorities, and discovered for himself the
summaries’ inaccuracies and the fact that one cited
adjudication did not exist. In response to our order, Attorney
disclosed, for the first time, that the seven summaries were
inaccurate and that one authority was hallucinated by AI. He
further admitted that he first suspected AI had been used in
“early February 2025,” and that he confirmed that AI had been
used to generate the underlying work product for the erroneous
summaries in “mid-February 2025.” Resp. to Text Order 4.

       We then ordered Attorney to show cause why he should
not be sanctioned pursuant to the Third Circuit Rules of
Attorney Disciplinary Enforcement (“Circuit Disciplinary
Rules”). In response, Attorney conceded that his conduct
violated our Circuit Disciplinary Rules and requested a
hearing, which was held on August 11, 2025.

II.    DISCUSSION

       A.     Violations of Disciplinary Rule 2.1




                                   4
        Pursuant to Third Circuit Disciplinary Rule 2.1(d), “[a]
member of the bar of this Court may be disciplined by this
Court as a result of … conduct that violates the Rules of … any
state, territory, or commonwealth of the United States to which
the respondent is subject.” Disciplinary Rule 2.1. Attorney is
subject to the Pennsylvania Rules of Professional Conduct
(“Pa. R.P.C.”).

              1.     Pa. R.P.C. 3.3, Duty of Candor to the
                     Court

        An attorney violates Pa. R.P.C. 3.3 by “knowingly[] …
mak[ing] a false statement of material fact or law to a tribunal
or fail[ing] to correct a false statement of material fact or law
previously made to the tribunal by the lawyer.” Pa. R.P.C.
3.3(a)(1). Attorney’s conduct may have violated Pa. R.P.C.
3.3(a) in various ways.

       First, in his Opening Brief, Attorney advanced a
meritless legal argument in that the argument relied upon non-
existent authority or was wholly unsupported by the
adjudications cited. Specifically, the adjudications were
misrepresented to, among other things, make it appear that the
DEA imposed lesser sanctions than those actually imposed in
those adjudications. This conduct may have violated Pa.
R.P.C. 3.3(a) because Attorney misrepresented the facts and
conclusions of the DEA adjudications. But Pa. R.P.C. 3.3 is
violated only when an attorney “knowingly” makes a false
statement. Pa. R.P.C. 3.3(a)(1). While Attorney mispresented
the legal authorities he cited, it is debatable whether he knew




                                   5
such statements were false as he failed to read the cases. 2
       Second, when alerted to these errors in his Opening
Brief, and despite his suspicions that the citations had been
generated by AI, Attorney did not correct those statements and
submitted additional mischaracterizations of the citations in
his Reply Brief. Reply Br. 14 (stating summaries were “a good
faith effort to chronicle Agency disparities, [and that there
were] some immaterial misstatements about the cited cases’
tangential details.”). Attorney thus may have violated Pa.

2
       Pennsylvania law suggests that reckless conduct may
violate Pa. R.P.C. 3.3(a) and Attorney’s continued failure to
verify    the    citations   and     subsequent      affirmative
mischaracterizations was plausibly reckless in view of his
knowledge that a non-attorney provided the content to him and
his suspicion that such content had been AI-generated. See
Off. of Disciplinary Couns. v. Wrona, 908 A.2d 1281, 1288
(Pa. 2006) (finding, among other rules, that Pa. R.P.C. 3.3 was
violated when attorney acted recklessly); id. (appearing to
adopt reckless standard without specifically addressing mens
rea required). Because the text of Pa. R.P.C. specifies knowing
conduct, and because the Pennsylvania Supreme Court has not
spoken to specifically say otherwise, we will not adopt a
reckless standard here.
       Our dissenting colleague highlights the applicability of
Pa. R.P.C. 3.3(a) Explanatory Comment 3 (Representations of
a Lawyer). We read that comment to be concerned with a
lawyer’s statements of fact and we read Explanatory Comment
4 (Legal Argument) to be concerned with statements of
law. See also Off. of Disciplinary Couns. v. Price, 732 A.2d
599, 603-04 (Pa. 1999) (analyzing Comment 3 in the context
of a lawyer’s statements of material fact).




                                  6
R.P.C. 3.3(a)(1) when he failed to correct false statements
made to the Court and when he asserted in his Reply Brief that
the citations were “immaterial misstatements” and “minor
discrepancies” about “tangential details.” Reply Br. 14. In
fact, these errors were not immaterial. The summaries
provided the primary support for Attorney’s argument that the
DEA’s actions were arbitrary and capricious. As Attorney
explained it, the summaries showed that the DEA “deviat[ed]
from its prior practice” without justification. Opening Br. 35.
This, according to Attorney, was an independently sufficient
reason to vacate the DEA’s decision. Opening Br. 25–26.
Nonetheless, Pa. R.P.C. 3.3 may not be implicated here. Given
that Attorney did not act with the normal diligence expected of
an attorney, it is again debatable whether he knowingly failed
to correct the false statements of fact and law contained in his
Opening Brief. It is similarly debatable whether he made the
mischaracterizations of his previous errors knowing they were
false.

       Finally, Attorney may also have violated Pa. R.P.C.
3.3(a) because he lacked any basis to state that the erroneous
authorities in the Opening Brief were cited in “good faith.” We
cannot conclude that Attorney did not know that the concept of
“good faith” is inconsistent with presenting legal authority that
he did not even verify existed. It is therefore likely that in
submitting this assertion to the Court, Attorney knowingly
made a false statement of fact to the tribunal. To violate Pa.
R.P.C. 3.3(a)(1), however, the false statement must be one of a
material fact. Attorney asserted his good faith when replying
to an argument made by the DEA. In responding to that
argument, Attorney’s good faith was immaterial.




                                   7
       On the whole, while we are deeply troubled by
Attorney’s cavalier stance towards his various submissions to
this Court, we do not find that he violated Pa. R.P.C. 3.3(a)(1).

              2.     Pa. R.P.C. 1.1, Duty to Provide
                     Competent Representation to a Client

        We caution, though, that Attorney’s continued
dereliction of minimal diligence implicates another Pa. R.P.C.,
namely Pa. R.P.C. 1.1. This rule requires an attorney to
“provide competent representation to a client” and specifies
that “[c]ompetent representation requires the legal knowledge,
skill, thoroughness and preparation reasonably necessary for
the representation.” Pa. R.P.C. 1.1. We conclude that
Attorney’s conduct violated R.P.C. 1.1 in that he failed to
exercise the “thoroughness [] necessary for the representation”
in this matter. This violation is a basis for discipline under
Circuit Disciplinary Rules 2.1(d).

       In the first instance, competent representation required
that Attorney be so thorough as to check all the citations in his
Opening Brief before signing and filing it. 3 This is especially

3
       In examining substantially identical rules, courts have
routinely found that the failure to verify the veracity and
authenticity of citations violates an attorney’s duty to provide
thorough and competent representation. See In re Martin, 670
B.R. 636, 648 (Bankr. N.D. Ill. 2025) (pursuant to ABA Model
Rule 1.1 attorneys have an “ethical obligations … to review
whatever cases they cite”); Benjamin v. Costco Wholesale
Corp., 779 F. Supp. 3d 341, 349 (E.D.N.Y. 2025) (plaintiff’s
attorney violated New York Rules of Professional Conduct




                                   8
the case given that the legal authorities and their substance
were provided to him by a non-attorney. 4 He chose not to
check the cites, however. Later, when he was alerted to the
inaccuracies in this brief, competent representation required


Rule 1.1 where she did not review AI generated research);
Dehghani v. Castro, 782 F. Supp. 3d 1051, 1060 (D.N.M.
2025) (“[a] lawyer’s failure to verify generative AI outputs can
implicate” Texas Rules of Professional Conduct Rule 1.1);
Puerto Rico Soccer League NFP, Corp. v. Federacion
Puertorriquena de Futbol, No. CV 23-1203 (RAM), 2025 WL
1080732, *3 (D.P.R. Apr. 10, 2025) (plaintiffs’ attorneys
violated ABA Model Rule 1.1 where they provided a “litany of
inaccurate information” to the court and provided citations to
caselaw that were either incorrect or did not exist); Robert
Thackston v. Daniel P. Driscoll, Secretary of the Army, No.
SA-24-CV-00276-FB-ESC, 2025 WL 2715267, *5 (W.D. Tex.
Aug. 28, 2025) (same); Hall v. Acad. Charter Sch., No. 2:24-
CV-08630-JMW, 2025 WL 2256653, *1 (E.D.N.Y. Aug. 7,
2025) (same); Davis v. Marion Cnty. Superior Ct. Juv. Det.
Ctr., No. 1:24-CV-01918-JRS-MJD, 2025 WL 2502308, *5
(S.D. Ind. Sept. 2, 2025) (same).
4
       Cf. Pa. R.P.C. 5.3 “Responsibilities Regarding
Nonlawyer Assistance,” cmt. 3 (advising that “a lawyer must
make reasonable efforts to ensure that the services [of a
nonlawyer] are provided in a manner that is compatible with
the lawyer’s professional obligations. The extent of this
obligation will depend upon the circumstances, including the
education, experience and reputation of the nonlawyer; [and]
the nature of the services involved” and referencing Pa. R.P.C.
1.1, among other Pa. R.P.C.s.)




                                  9
that he be so thorough as to check the authorities in his Opening
Brief (and Pa. R.P.C. 3.3 would then have required he submit
appropriate corrections to the Court). He again chose not to do
so. Unfortunately, Attorney’s lack of diligence continued
when he stated in his Reply Brief, wholly without basis, that
his citations to these authorities were “immaterial
misstatements” and “minor discrepancies” about “tangential
details.” Reply Br. 14. Attorney’s myriad failures led to all of
the problems highlighted above. In light of this lack of
thoroughness, we find that Attorney violated Pa R.P.C. 1.1 and
Circuit Disciplinary Rule 2.1(d). 5

       B.     Sanctions

       A panel of this Court “may impose any sanction other
than suspension or disbarment.” 6 Circuit Disciplinary Rule 4.1.
“Discipline may consist of … monetary sanction, removal
from the roster of attorneys eligible for appointment as Court-
appointed counsel, reprimand, or any other sanction that the

5
       This Court also alerted Attorney that it would consider
whether his conduct violated Circuit Disciplinary Rule 2.1(e)
(providing for discipline based upon conduct “unbecoming a
member of the bar of this Court”) and the hearing in this matter
touched upon whether Attorney’s conduct implicated Local
Appellate Rules 28.4 and 46.4 (requiring signature), as
informed by Fed. R. Civ. P. 11. We do not reach that issue
here as we find Pa. R.P.C. 1.1 and Circuit Disciplinary Rule
2.1(d) adequately address Attorney’s conduct.
6
       Suspension or disbarment may be imposed by this
Court’s Standing Committee on Attorney Discipline. See
Circuit Disciplinary Rules 4.1, 4.2.




                                  10
Court or a panel thereof may deem appropriate.” Circuit
Disciplinary Rule 3.1.

       Here, Attorney has wasted the time and resources of this
Court and the Government due to his failure to verify, at
multiple points in time, authorities that he submitted to this
Court; his doubling-down on that conduct by submitting yet
another brief in which he characterized his complete lack of
legal research as a “good faith effort;” his characterization of
the misrepresentations as “immaterial” and related to
“tangential details,” although having never read the authorities
and having no basis to make such assertions, Reply Br. 14; and
his failure to timely verify and report his knowledge of
inaccuracies.

       Moreover, Attorney has harmed his credibility with this
Court. As Attorney signed his brief and submitted it as an
officer of the Court, this Court initially credited Attorney with
earnest, but mistaken, efforts in offering legal authority to this
Court. It was highly disappointing to learn that Attorney’s
status as an officer of the Court did not prevent him from
blindly submitting erroneous authority and to learn that this
Court’s confidence in him was misplaced.

        On one hand, Attorney’s conduct is somewhat mitigated
by the actions he took after our show-cause order. Attorney
has displayed sincere contrition. He has been forthcoming and
admitted his many failures to this Court without minimizing
his conduct. Attorney also states that he has taken corrective
measures to prevent a similar incident from occurring in the
future. On the other hand, the mitigating force of Attorney’s
remedial conduct is lessened by the fact that he only made such
efforts after we issued the show cause order. That he was not




                                   11
already verifying the accuracy of all citations in his briefs is
itself concerning.

        In considering sanctions, we also find mitigating the
fact that this Court has not yet addressed the failure of attorneys
to use AI with appropriate guardrails. 7 While Attorney had
ample reason to question the reliability of the authorities he
submitted, and arguably had reason to know the pitfalls of AI, 8
this Court has not yet had the opportunity to speak on the issue
and emphasize that, when using AI, litigants must still strictly
adhere to all rules of professional conduct. Moreover, we are
mindful that in issuing the show cause order, this Court did not


7
       With the rapid advancement of this technology, there
have been missteps by a variety of participants in the legal
system, from junior members of the bar to judges
themselves. It is incumbent upon all participants to adhere to
professional standards governing their work. See, e.g., Jud.
Conf. Comm. on Codes of Conduct, Guidance for Ethical Use
of AI in the Judiciary, Section F “Accountability, accuracy,
and the need for verification” (February 2, 2026) (citing Code
of Conduct, Canon 3B and Judiciary’s Interim Guidance,
III(A)(4)).
8
       Two years ago, an attorney submitting fake cases
generated by AI was described as “unprecedented.” Mata v.
Avianca, Inc., 678 F. Supp. 3d 443, 461 (S.D.N.Y. 2023).
Unfortunately, that is no longer the case. See, e.g., Johnson v.
Dunn, --- F. Supp. 3d ---, No. 2:21-cv-1701, 2025 WL
2086116, at *11 (N.D. Ala. July 23, 2025) (compiling cases
involving fabricated authorities).




                                   12
ask Attorney to address Pa. R.P.C. 1.1.9 While our Circuit
Disciplinary Rules do not require us to notify an attorney of
each rule that may have been violated, see Circuit Disciplinary
Rule 4.1 (requiring only that an attorney be notified of “the
alleged conduct which may justify the imposition of
discipline”), we nonetheless find Attorney’s lack of
opportunity to address this rule to be a mitigating factor in
deciding what discipline to impose.

       Considering the above, the Court will impose the
sanction of a reprimand. Pursuant to our Disciplinary Rules,
“the Clerk will notify … all other courts before whom
[Attorney] is admitted to practice and the National Disciplinary
Data Bank” of this discipline and provide them with a copy of
the opinion imposing this discipline. Circuit Disciplinary Rule
12. Had this not been our first opportunity to address the use
of AI, and had we given notice that we would consider whether
Attorney’s conduct violated Pa. R.P.C. 1.1, it is likely that
monetary sanctions would have been imposed here. As this
precedent has now been set, the first mitigating factor will not
apply in the future and violators may well face any of the
sanctions available per Circuit Disciplinary Rules 4.1-4.2.

      Our decision is neither a critique nor a comment upon
Attorney’s reliance on others in conducting research, nor the

9
        When this Court issued the Order to Show Cause, it was
under the misimpression that, when Attorney confirmed that
AI had been used to draft portions of the Opening Brief, he also
confirmed that the summaries were incorrect and that one
authority did not exist. Accordingly, the Court’s focus was
Attorney’s duty of candor to the Court in not disclosing those
errors.




                                  13
use of AI generally. With proper supervision and vetting, both
may be helpful to an attorney. Nor are perfect summaries and
citations needed to avoid sanctions. Mistakes do happen. Our
decision to impose sanctions is due to Attorney’s overall
conduct over the course of months. Had he checked the
citations upon receiving the Government’s brief and then
informed us that the citations were inaccurate, our decision
today would be different. Had he taken reasonable efforts to
ensure the reliability of his Opening Brief in the first place, we
would not be here at all.

III.   CONCLUSION

      For the foregoing reasons, Mr. Pallen will be sanctioned
accordingly.




                                   14
     McCarthy v. U.S. Drug Enforcement Administration

                   No. 24-2704
_________________________________________________

ROTH, Circuit Judge, concurring in part and dissenting in
part.

        Although I agree with my colleagues that Daniel
Pallen’s (Attorney) violations of Pa. R.P.C. 1.1 and Circuit
Disciplinary Rule 2.1(d) warrant sanctions, I write separately
because I would have imposed sanctions more severe than the
Majority deems appropriate. In my view, the Majority
incorrectly attaches an inapplicable standard of culpability to
Pa. R.P.C. 3.3(a)(1)—a rule which Attorney violated on at least
two occasions. The sanctionable conduct is not merely
Attorney’s filing of a brief with incorrect and hallucinated
citations, but also his subsequent actions, inactions, and lack of
candor that continued until he was eventually held accountable
by this Court.

   I.     Attorney Violated Pa. R.P.C. 3.3(a)(1) Because
          He Falsely Asserted Legal Arguments Without a
          Belief Based on a Reasonably Diligent Inquiry

       The Majority hesitates to conclude that Attorney
violated Pa. R.P.C. 3.3(a)(1) because they are unsure whether
he knew the AI-generated case summaries and analyses
asserted in his Opening Brief were false. I agree with the
Majority that a knowing standard of culpability would apply to




                                1
any factual assertions within the Opening Brief. 1 However,
the Majority need only read the comments to Pa. R.P.C. 3.3 to
see that the Pennsylvania Supreme Court distinguishes facts
relevant to a client’s case—for which a knowingly standard of
culpability would apply—from legal argument in support
thereof:

       An advocate is responsible for pleadings and
       other documents prepared for litigation, but is
       usually not required to have personal knowledge
       of matters asserted therein, for litigation
       documents ordinarily present assertions by the
       client, or by someone on the client’s behalf, and
       not assertions by the lawyer. Compare Rule 3.1.
       However, an assertion purporting to be on the
       lawyer’s own knowledge, as in an affidavit by
       the lawyer or in a statement in open court,
       may properly be made only when the lawyer
       knows the assertion is true or believes it to be
       true on the basis of a reasonably diligent
       inquiry. 2

      Within the same Rules of Professional Conduct, the
Pennsylvania Supreme Court recognizes that analysis of
precedent is a legal skill covered under an attorney’s duty of
competence. 3 While Attorney was not required to have first-


1
  See Pa. R.P.C. 3.3(a)(1) (“A lawyer shall not knowingly make
a false statement of material fact or law to a tribunal or fail to
correct a false statement of material fact or law previously
made to the tribunal by the lawyer[.]”) (emphasis added).
2
  Pa. R.P.C. 3.3 cmt. 3 (emphasis added).
3
  See Pa. R.P.C. 1.1 cmt. 2.




                                2
hand knowledge of every facet of his client’s factual history,
the Pennsylvania Rules of Professional Conduct prohibited
him from blindly accepting his client’s legal research as
accurate. If Attorney wanted to demonstrate the DEA’s “lack
of reasoned decision-making” and use prior caselaw to explain
that the agency “acted arbitrarily and capriciously,” his
reasoning must have been purported on his own knowledge. 4

       The relevant analysis under Pa. R.P.C. 3.3(a) is not
whether Attorney knew he was including miscited and
hallucinated caselaw in his Opening Brief. Rather, the
question is whether Attorney knew his analyses of the cases
were true, or at minimum whether he believed those analyses
were true based on a reasonably diligent inquiry. 5 Yet
Attorney never conducted any inquiry whatsoever. Instead, he
incorporated his client’s AI-generated legal research into the
Opening Brief without checking the veracity (or even
existence) of those cases. Such conduct squarely violates Rule
3.3(a)(1).

    II.   Attorney’s Actions After Receiving Notice of His
          Mistakes in the Opening Brief Are More
          Egregious Than Mere Mistakes

        Had Attorney’s violations been limited to incorrect
citations, I would be more inclined to agree with my colleagues


4
  Opening Br. 35.
5
  See Off. Of Disciplinary Couns. v. Price, 732 A.2d 599, 605
(Pa. 1999) (holding that an attorney violated Pa. R.P.C.
3.3(a)(1) because he “relied on rumors, innuendo and his own
perceptions” instead of “conducting a reasonably diligent
inquiry into the accuracy of his statements.”).




                              3
about the severity of the sanctions imposed. I am troubled,
however, by Attorney’s conduct after the government spent
four pages of its Response Brief discussing the errors for each
of the eight incorrect citations. This would have been the
opportune time for Attorney to recognize and remedy his
mistakes.

       Instead of acknowledging the errors made in his
Opening Brief, Attorney put his nose in the air and accused the
government of “disregard[ing] the forest for the trees.” 6 A
defense of mischaracterized caselaw, like an analysis of
precedent, is a legal skill. When Attorney dismissed his
erroneous caselaw analyses as “some immaterial
misstatements about the cited cases’ tangential details,” he was
required under Pa. R.P.C. 3.3(a) to know that his statements
were true, or believe them to be true after conducting a
reasonably diligent inquiry. 7 It is difficult to understand how
Attorney could defend the truth of his statements when he
never bothered to read the cases, even after filing his Reply
Brief. Accordingly, Attorney’s statements in defense of his
miscited and hallucinated caselaw in his Reply Brief constitute
additional violations of Pa. R.P.C. 3.3(a).

       Yes, mistakes do happen. 8 Yet even if we call
Attorney’s initial lapse of judgment a mistake, we should not
say the same about Attorney’s actions after the government put
him on notice in its Response Brief. Attorney confirmed in
early February 2025—shortly after filing his Reply Brief on
February 6, 2025—that his client had used AI to generate the

6
  Reply Br. 14.
7
  Reply Br. 14.
8
  See Maj. Op. 12.




                               4
research, including the erroneous caselaw in his Opening Brief.
But Attorney chose to sit on his hands. The Majority
adequately described why Attorney’s conduct violated Pa.
R.P.C. 1.1 and Circuit Disciplinary Rule 2.1(d). However,
attorneys practicing before this Court should not be permitted
to stick their heads in the sand and pray that ignorance will
preclude them from upholding their professional
responsibilities.

     III.   This Court Does Not Need to Warn Attorneys to
            Use Artificial Intelligence Responsibly

       Finally, I write to comment on the Majority’s hesitation
to impose monetary sanctions because we have not yet
addressed the use of AI in a precedential opinion. 9 We need
not explicitly forewarn against improper AI use when it falls
within the strictures on legal argument of Pa. R.P.C. 3.3.
Moreover, we can take notice of the numerous courts across
the country that have already addressed attorneys’ obligation
to take ownership over their work product. We have seen
federal appellate courts admonish attorneys for filing briefs
with hallucinated cases. 10 We have seen federal district
courts—including within this Circuit—discipline attorneys for
not checking work provided to them by clients. 11 We have
seen state courts sanction lawyers for blindly relying on


9
  Supra Maj. Op. 12.
10
   See Park v. Kim, 91 F.4th 610, 613–15 (2d Cir. 2024); Grant
v. City of Long Beach, 96 F.4th 1255, 1257 (9th Cir. 2004).
11
   See, e.g., Bevins v. Colgate-Palmolive Co., No. 25-cv-576,
2025 WL 1085695, at *7 (E.D. Pa. Apr. 10, 2025); Bunce v.
Visual Tech. Innovations, Inc., No. 23-cv-1740, 2025 WL
662398, at *3–4 (E.D. Pa. Feb. 27, 2025).




                              5
generative-AI to conduct caselaw research. 12 What’s more,
such lapses in judgment are no longer confined to the legal
community, as publications by national media broadcast these
errors to the public. 13

       Although Attorney did not ask for leniency on this
ground, the Majority appears to adopt the reasoning of an
attorney who filed briefing with fake caselaw hallucinated by
an AI-program before the United States Court of Appeals for
the Second Circuit. In Park v. Kim, the attorney argued that
she should not be sanctioned because the court had not yet
issued guidance advising lawyers to exercise caution when


12
   See, e.g., Ader v. Ader, 87 Misc.3d 1213(A), 2025 WL
2831332, at *3–4 (N.Y. Sup. Ct. Oct. 1, 2025); Smith v.
Farwell, No. 2282CV01197, 2024 WL 4002576, at *4–5, *7
(Mass. Dist. Ct. Feb. 15, 2024).
13
   See, e.g., Larry Neumeister, Lawyers submitted bogus case
law created by ChatGPT. A judge fined them $5,000,
ASSOCIATED           PRESS        (June         22,       2023),
https://apnews.com/article/artificial-intelligence-chatgpt-fake-
case-lawyers-d6ae9fa79d0542db9e1455397aef381c
[https://perma.cc/8KRK-6VUW]; Benjamin Weiser and Jonah
E. Bromwich, Michael Cohen Used Artificial Intelligence in
Feeding Lawyer Bogus Cases, N.Y. TIMES (Dec. 29, 2023),
https://www.nytimes.com/2023/12/29/nyregion/michael-
cohen-ai-fake-cases.html      [https://perma.cc/ZNY2-B9HA];
Michael Lee, Lawyer in hot water after using AI to present
made up information: ‘incompetent’, FOX (Feb. 7, 2024),
https://www.foxnews.com/us/lawyer-hot-water-after-using-
ai-present-made-up-information-incompetent
[https://perma.cc/64BZ-9U7D].




                               6
utilizing artificial intelligence. 14 The Park court correctly
rejected that argument, emphasizing that a rule about artificial
intelligence use “is not necessary to inform a licensed attorney,
who is a member of the bar of this Court, that she must ensure
that her submissions to the Court are accurate.” 15

       My comments should not be taken to persuade against
the use of AI. I agree with my colleagues that such technology
may be useful when used with proper supervision and vetting.
But punishing an attorney for failure to verify information
obtained from AI is consistent with the standard to which
attorneys historically have been held. No forewarning is
necessary when it is clear what standard the attorney was
required to follow. The ethical practice of the law is innate in
the responsibilities of each practicing attorney. It needs no
reminder as each case is accepted and resolved.




14
     Park, 91 F.4th at 613–15.
15
     Park, 91 F.4th at 615 (emphasis omitted).




                                7