USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 1 of 17
UNPUBLISHED
UNITED STATES COURT OF APPEALS FOR THE FOURTH CIRCUIT
No. 25-1190
EXCLUSIVE JETS, LLC, d/b/a Fly Exclusive,
Petitioner,
v.
UNITED STATES DEPARTMENT OF LABOR, ADMINISTRATIVE REVIEW BOARD,
Respondent,
and
MICHAEL J. JONES,
Intervenor.
On Petition for Review of an Order of the United States Department of Labor, Administrative Review Board. (2023-0035)
Submitted: March 2, 2026 Decided: April 30, 2026
Before WYNN and QUATTLEBAUM, Circuit Judges, and FLOYD, Senior Circuit Judge.
Petition for review granted in part and denied in part; vacated in part and remanded by unpublished opinion. Judge Wynn wrote the opinion, in which Judge Quattlebaum and Senior Judge Floyd joined. USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 2 of 17
ON BRIEF: Zebulon D. Anderson, Danielle B. Dobosz, SMITH, ANDERSON, BLOUNT, DORSETT, MITCHELL & JERNIGAN, LLP, Raleigh, North Carolina, for Petitioner. Jonathan L. Snare, Acting Solicitor of Labor, Jennifer Brand, Associate Solicitor, Sarah K. Marcus, Deputy Associate Solicitor, Jennifer Huggins, Karla Jackson Edwards, Office of the Solicitor, UNITED STATES DEPARTMENT OF LABOR, Washington, D.C., for Respondent. Morgan W. Campbell, FOX ROTHSCHILD, LLP, Washington, D.C., for Intervenor.
Unpublished opinions are not binding precedent in this circuit.
2 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 3 of 17
WYNN, Circuit Judge:
Under the whistleblower protection program established by the Wendell H. Ford
Aviation Investment and Reform Act for the 21st Century (“Aviation Reform Act”),
49 U.S.C. § 42121, an employee who proves being discharged by an employer for
reporting aviation safety concerns, is entitled to relief, subject to the duty to mitigate
damages under the proper legal standard.
In this matter, after Exclusive Jets, LLC fired Michael Jones, a Department of Labor
administrative law judge (“ALJ”) found that Jones had established that his discharge
violated the Aviation Reform Act, and the Administrative Review Board (“ARB”)
affirmed. Although we hold that the ARB properly affirmed the ALJ’s liability
determination, we conclude that it evaluated Jones’s mitigation efforts under a “gross or
egregious conduct” standard instead of the proper “reasonable diligence” standard.
Thus, we grant in part and deny in part the petition for review and remand to the
ARB with instructions to apply the correct legal standard to assess Jones’s duty to mitigate
damages.
I.
A.
In reciting the following facts, we remember that this Court reviews the agency’s
factual findings deferentially, upholding them if they are “supported by substantial
evidence.” Northrop Grumman Sys. Corp. v. U.S. Dep’t of Lab., 927 F.3d 226, 232 (4th
Cir. 2019).
3 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 4 of 17
On January 3, 2018, Exclusive Jets president Mike Guina sent an email to all its
pilots asking them to share their concerns, acknowledging that previous pilot feedback had
not led to clear changes and that the pilots had heavy workloads. Jones, who was then
working for the company as a First Officer, responded with a lengthy email that raised
many concerns. He alleged, among other things, that flight crews and captains did not want
to document aircraft defects, which posed a safety issue. Guina forwarded this email to the
company’s director of operations, Jon Heuman.
Around the same time, Exclusive Jets asked fleet lead pilot Dominic Publico to
evaluate Jones. After flying with Jones for about a week, Publico sent an email criticizing
Jones’s attitude and flying abilities and recommending that Exclusive Jets fire Jones.
Exclusive Jets rejected that recommendation.
Instead, in May 2018, Exclusive Jets promoted Jones from First Officer to Captain.
Heuman, Guina, and others thought that “a lot of [Jones’s] complaints” seemed to stem
from his opinion “that he should be captain,” and so the promotion might “have a positive
change on his behavior.” J.A. 3124. 1
But Jones continued to raise safety issues. In June 2018, Jones reported an issue
with a wind screen, which meant that the plane should not be flown in known icing
conditions. Guina called Jones, agreeing that “it would be [Jones’s] call” but that he would
“hate to think that the flight wouldn’t go.” J.A. 2658, 2661. Jones completed the flight,
flying at a lower altitude to avoid icing conditions.
1 Citations to the “J.A.” refer to the Joint Appendix filed by the parties in this matter. 4 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 5 of 17
A few days after this exchange, Guina invited Jones to a meeting to discuss Jones’s
grievances. Present at the meeting were Jones, Guina, Heuman, chief pilot Scott Petersen,
and director of maintenance Darryl Shearer. There, Jones began reciting his list of
problems, many of which were issues that he had discussed in his January email. Attendees
uniformly called the meeting hostile, unproductive, and relatively short.
From August 2018 to January 2019, several First Officers complained about
working with Jones. In December 2018, Publico emailed Jones that no First Officers
wanted to work with him because his “attitude in the cockpit ha[d] become toxic.” J.A.
2136.
Jones continued to report safety concerns, which sometimes led to aircraft being
grounded. Heuman testified that his impression during Jones’s employment was that he
“had more aircraft write-ups than anybody in the company.” 2 J.A. 3187.
Jones began what would turn out to be his final eight-day rotation with Exclusive
Jets on February 5, 2019. That day, Jones noticed issues that made his assigned aircraft not
airworthy, and it was eventually grounded. Previous crews had not noticed or had not
documented these mechanical irregularities. On February 6, he sent an email to Exclusive
Jets’ maintenance supervisor that listed the irregularities, copying Heuman, Petersen, and
Publico. He also entered the irregularities into the aircraft’s logbook. 3 A maintenance
2 That impression turns out to have been incorrect, as Exclusive Jets discovered during the ensuing litigation. 3 An aircraft logbook is the record of an aircraft’s operation and maintenance history. See 14 C.F.R. § 135.65 (providing that each aircraft must “carr[y] on board” an “aircraft maintenance log . . . for recording or deferring mechanical irregularities and their correction”). 5 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 6 of 17
supervisor commended Jones and wrote that he couldn’t “believe [the plane had] been
flying round all this time and nobody else caught it.” J.A. 3489.
The plane was apparently repaired and set to return to service on February 7. That
day, however, Exclusive Jets manager Josh Golden emailed Heuman and Guina that Jones
was “already at the plane” and was writing up so many additional safety concerns about it
that Golden believed Jones “clearly” had previously “sav[ed] some things” to report about
it. J.A. 1934. Golden further wrote that he and another manager had “agreed that if Jones
does not make his flights today then we will send him home, and we will bring [another
pilot] out to replace him. I am done.” Id.
The next day, Jones was assigned to perform a maintenance test flight on another
aircraft, but he emailed Heuman, Petersen, and others that he was concerned about
conducting the test flight in poor weather conditions. Fourteen minutes later, Guina
emailed Petersen stating, “We have to get this under control,” J.A. 2958, which he later
testified was because he wanted “the flight to happen if” it could, J.A. 2960. While the
question of whether to proceed with the test flight was still pending, Jones’s wife called to
tell him that she had looked at his schedule and seen that he was now “on standby for
eternity”—that is, he had been removed from his next (previously assigned) rotation and
had no further rotations scheduled. J.A. 2492.
The test flight ultimately had to be rescheduled after Jones’s First Officer was
injured during the pre-flight inspection. Jones completed the test flight two days later, on
February 10, with another pilot. Afterward, the other pilot told Jones to go home, even
though Jones still had two days left in his rotation. Jones did not hear anything further from
6 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 7 of 17
Exclusive Jets for more than two weeks. On February 27, Petersen called to tell Jones that
he was being fired for not being “a good fit.” J.A. 2501.
Jones then attempted to find another job. On March 25, 2019, Gama Aviation
offered him a job as a captain. Jones completed many parts of the onboarding process, but
Gama Aviation withdrew its offer after Jones did not timely submit the training agreement.
Jones attempted twice to call the recruiter to smooth things over, but to no avail.
Jones continued to look for work as a pilot, but he accepted jobs at Walmart in 2020
and for the City of Rockledge in 2021. In September 2021, JetBlue hired him as a pilot.
B.
In March 2019, Jones filed a complaint with the Occupational Safety and Health
Administration (“OSHA”), alleging that he had been fired “in retaliation for grounding
aircraft for safety and mechanical issues and for identifying potential violations under
AIR21.” J.A. 3. OSHA dismissed the complaint after determining that its investigatory
evidence did not show that Jones’s termination was in retaliation for engaging in protected
activity. Jones objected to OSHA’s findings and requested a hearing before an ALJ.
After the parties completed discovery, the ALJ conducted evidentiary hearings and
received post-hearing briefs. Ultimately, the ALJ concluded that Jones had prevailed and
was entitled to damages for back pay, emotional harm, and costs and attorneys’ fees.
Exclusive Jets appealed, and the ARB affirmed in relevant part. 4 Exclusive Jets then
timely petitioned this Court for review.
4 The ARB agreed with Exclusive Jets on its challenge to the method for calculating interest on the back-pay award, but that issue is not before us. 7 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 8 of 17
II.
We review the ARB’s determinations under the Administrative Procedure Act, and
thus we disturb its decision only if that decision “was arbitrary, capricious, an abuse of
discretion, or otherwise not in accordance with law.” Northrop Grumman, 927 F.3d at 232
(cleaned up). We review questions of law de novo, and we uphold factual findings “if
supported by substantial evidence.” Id. “Similarly, the ARB reviews ‘the factual
determinations of the ALJ under the substantial evidence standard.’” Greatwide Dedicated
Transp. II, LLC v. U.S. Dep’t of Lab., 72 F.4th 544, 552 (4th Cir. 2023) (quoting 29 C.F.R.
§ 1978.110(b)). “Substantial evidence is such relevant evidence as a reasonable mind might
accept as adequate to support a conclusion.” Easterbrook v. Kijakazi, 88 F.4th 502, 511
(4th Cir. 2023) (cleaned up).
III.
An Aviation Reform Act claim requires a complainant to “present a prima facie case
demonstrating by a preponderance of the evidence that: (i) they engaged in protected
activity, (ii) the employer knew of the protected conduct, (iii) their employer took an
unfavorable employment action against them, and (iv) the protected activity was a
contributing factor to the employer’s adverse employment action.” 5 Greatwide, 72 F.4th at
553.
5 This burden-shifting framework is shared across several federal whistleblower statutes, including the Sarbanes-Oxley Act, and thus we look generally to the cases applying that framework. See Feldman v. L. Enf’t Assocs. Corp., 752 F.3d 339, 344 (4th Cir. 2014) (noting that Sarbanes-Oxley whistleblower claims incorporate the Aviation Reform Act’s burden-shifting framework). 8 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 9 of 17
Once a complainant has established a prima facie case, “the burden shifts to the
employer to demonstrate, by clear and convincing evidence, that the employer would have
taken the same unfavorable personnel action in the absence of that protected behavior.” Id.
at 553–54 (cleaned up); see 49 U.S.C. § 42121(b)(2)(B). Once liability is established, the
agency orders a remedy that includes back pay and other compensatory damages. See 49
U.S.C. § 42121(b)(3)(B). However, a complainant’s ability to claim back pay is limited by
a duty to mitigate damages. See O’Neal v. Gresham, 519 F.2d 803, 805 (4th Cir. 1975)
(explaining that the duty to mitigate applied to an “improperly discharged employee” in a
42 U.S.C. § 1983 discharge case just as it did “in any other” employment case); Brady v.
Thurston Motor Lines, Inc., 753 F.2d 1269, 1273 (4th Cir. 1985).
Exclusive Jets challenges the ARB’s conclusion that there was substantial evidence
to support the ALJ’s determinations (1) that Jones engaged in protected activity, (2) that
Jones’s protected activity was a contributing factor in his termination, (3) that Exclusive
Jets failed to demonstrate by clear and convincing evidence that it would have terminated
Jones absent his protected activity, and (4) that Jones mitigated his damages. We disagree
on the first three points, but we vacate and remand for further proceedings on the fourth.
We begin with protected activity. An employee engages in protected activity by
providing “information regarding violations ‘relating to air carrier safety’ to his or her
employer or federal authorities.” Lawson v. FMR LLC, 571 U.S. 429, 434 (2014) (quoting
49 U.S.C. § 42121(a)(1)).
9 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 10 of 17
Though we have not opined on the matter, we find ARB precedent on the issue
helpful. Under those decisions, a “logbook entry in and of itself” does not necessarily
constitute protected activity. Luder v. Cont’l Airlines, Inc., ARB No. 10-026, 2012 WL
376755, at *5 (Dep’t of Lab. Jan. 31, 2012). Nor does “‘[c]ompetently’ and ‘aggressively’
carrying out duties to ensure safety.” Sievers v. Alaska Airlines, Inc., ARB No. 05-109,
2008 WL 316012, at *4 (Dep’t of Lab. Jan. 30, 2008). However, related activities may be
protected. See, e.g., id. at *4 (informing an airline manager about an incident and refusing
to sign off on a plane’s airworthiness); Douglas v. Skywest Airlines, Inc., ARB Nos. 08-
070, 08-074, 2009 WL 3165859, at *5 (Dep’t of Lab. Sep. 30, 2009) (declaring a crew
unfit to fly and informing supervisors); Hirst v. Se. Airlines, Inc., ARB Nos. 04-116, 04-
160, 2007 WL 352447, at *4 (Dep’t of Lab. Jan. 31, 2007) (raising safety concerns with
the airline’s flight operations director and questioning the legality of flying an airplane with
increased weight).
Here, the ALJ determined that Jones’s “logbook entries were protected activity.”
J.A. 3509. The ALJ then went on to consider the causal link between “the February 7, 2019
events” and Jones’s “termination less than three weeks later.” J.A. 3513. Those events
included, for example, Golden’s correspondence following Jones’s reports to maintenance
control that expressed frustration about whether Jones would “make his flights today”
because of his continued reporting. J.A. 1934.
Upon review, the ARB concluded that the ALJ had erred to the extent the ALJ
applied a per se rule that logbook entries are protected activity. But the ARB then
concluded that any error was harmless because Jones’s “actions on February 5–8, 2019
10 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 11 of 17
went beyond mere logbook entries and unquestionably constitute protected activity,” J.A.
3975, and it was clear from the ALJ’s analysis that the ALJ considered more than simple
logbook entries.
We find no error—legal or factual—in that conclusion.
Legally, the ARB did not err in forgiving the ALJ’s “misstatement,” J.A. 3975, that
logbook entries constitute per se protected activity because the ALJ had made other factual
findings that together rose to the level of protected activity. Sea “B” Mining Co. v. Addison,
831 F.3d 244, 253 (4th Cir. 2016) (“Administrative adjudications are subject to the same
harmless error rule that generally applies to civil cases.”).
Factually, the ARB did not err in determining that substantial evidence supported
the ALJ’s ultimate conclusion that Jones engaged in protected activity. As the ARB noted,
the ALJ cited more than just the instances in which Jones had “not[ed] mechanical
irregularities in an aircraft’s logbook.” J.A. 3975. The ALJ’s analysis also included factual
findings that, between February 5 and 8, Jones notified a manager about a software
compatibility issue, called the manufacturer of the flight management system, made ten
logbook entries, emailed a list of mechanical issues to maintenance control and Exclusive
Jets executives, and emailed executives about weather concerns. Taken as a whole, those
factual findings were more than sufficient to support an overall finding that Jones had
engaged in protected activity under the Aviation Reform Act.
Thus, the ARB properly affirmed the ALJ’s findings and conclusions regarding
protected activity.
11 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 12 of 17
Next, we consider contributing-factor causation. “A contributing factor is ‘any
factor, which alone or in combination with other factors, tends to affect in any way the
outcome of the decision.’” Feldman v. L. Enf’t Assocs. Corp., 752 F.3d 339, 348 (4th Cir.
2014) (quoting Allen v. Admin. Rev. Bd., 514 F.3d 468, 476 n.3 (5th Cir. 2008)). The
contributing-factor test “is specifically intended” to supplant case law that requires “a
whistleblower to prove that his protected conduct was a ‘significant,’ ‘motivating,’
‘substantial,’ or ‘predominant’ factor.” Id. (quoting Marano v. Dep’t of Just., 2 F.3d 1137,
1140 (Fed. Cir. 1993)). The Supreme Court has emphasized that the contributing-factor
standard “reflects a judgment that personnel actions against employees should quite simply
not be based on protected whistleblowing activities—not even a little bit.” Murray v. UBS
Sec., LLC, 601 U.S. 23, 36–37 (2024) (cleaned up).
Here, in concluding that Jones’s protected activity was a contributing factor to his
termination, the ALJ and ARB relied heavily on Heuman’s testimony that “a secondary
reason [Jones] was terminated is because he engaged in malicious compliance” by delaying
reporting a mechanical issue until a time that was convenient for him. J.A. 3191; see J.A.
3187–88 (explaining “malicious compliance” as meaning that a pilot might think, “I want
to go out to dinner in Salt Lake City so I’m going to wait until [I’m] there and write [my
report] up then”). Exclusive Jets argues that was error because Heuman’s admission was
only that Exclusive Jets fired Jones in part for delaying a report, not necessarily filing a
report.
But that argument fails for two reasons.
12 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 13 of 17
First, what Heuman describes as “malicious compliance” has two components:
delay and compliance. Indeed, Heuman agreed that if Jones’s reports were not held back,
“it’s not malicious compliance, it’s just compliance.” J.A. 3194. Thus, the ALJ’s finding
that there was “no credible evidence” that Jones’s reports were “maliciously held for a later
time” supports the ALJ’s conclusion that Exclusive Jets was motivated by the act of
compliance itself, rather than any purported delay. J.A. 3508.
Second, as the ARB found, other evidence in the record corroborated the ALJ’s
finding that Heuman was actually admitting to firing Jones for protected activity. As Jones
sat on a plane drafting reports, an Exclusive Jets employee wrote an email stating that
Exclusive Jets employees had “agreed that if Jones does not make his flights today then we
will send him home.” J.A. 1934. Other evidence showed that Exclusive Jets had repeatedly
labeled Jones “a high producer” of safety reports, lending support to the idea that what
concerned Exclusive Jets about Jones was his filing of the reports, not merely their delay.
J.A. 3509. And Heuman separately testified that whereas other pilots had been counseled
about malicious compliance, Jones had not, undermining the suggestion that Exclusive Jets
was concerned about Jones’s engaging in this behavior.
At bottom, Exclusive Jets asks us to reweigh the evidence and interpret Heuman’s
testimony differently than the ALJ did. The ARB properly declined to do so, and we would
err if we did otherwise. See Johnson v. Barnhart, 434 F.3d 650, 653 (4th Cir. 2005)
(quoting Craig v. Chater, 76 F.3d 585, 589 (4th Cir. 1996)) (“In reviewing for substantial
evidence, we do not undertake to reweigh conflicting evidence, make credibility
13 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 14 of 17
determinations, or substitute our judgment for that of the [ALJ].”). The ARB properly
affirmed the ALJ’s causation determination. 6
C.
Next, we consider Exclusive Jets’ same-decision defense. Once a complainant
establishes a prima facie case, an employer may nevertheless avoid liability if it
demonstrates, “by clear and convincing evidence, that [it] would have taken the same
unfavorable personnel action in the absence of that protected behavior.” Greatwide, 72
F.4th at 553–54 (citation omitted). It is not enough for the employer to prove that it “could
have” taken the same action; rather, the employer must show that it “would have” fired the
employee in the absence of his protected activity. Parker v. BNSF Ry. Co., 137 F.4th 957,
964 (9th Cir. 2025); see also Murray, 601 U.S. at 38 (quoting Bostock v. Clayton County,
590 U.S. 644, 656 (2020)) (“The right way to think about that kind of same-action causation
analysis is to ‘change one thing at a time and see if the outcome changes.’”).
The ALJ found that Exclusive Jets had shown “a preponderance of evidence that it
could have” fired Jones in the absence of his reports, but it had not established “by clear
and convincing evidence that it would have done so.” J.A. 3515. The ARB affirmed, again
under a substantial-evidence standard.
6 Exclusive Jets also argues that, discounting Heuman’s testimony, evidence of temporal proximity alone was insufficient to support a causality finding. Because we conclude that the ARB properly affirmed the ALJ’s finding regarding Heuman’s testimony, we do not reach this argument. 14 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 15 of 17
Exclusive Jets argues that the ALJ failed to consider all of its evidence and that the
ARB impermissibly focused on the merits of the termination rather than the truthfulness of
Exclusive Jets’ proffered reason for firing Jones. We disagree.
First, the ALJ extensively evaluated Exclusive Jets’ evidence. The ALJ reviewed
evidence that Jones was “difficult to work with,” J.A. 3493, and noted instances in which
the ALJ accorded certain evidence little weight or found witnesses more or less credible.
Second, the ARB did not require Exclusive Jets to defend the merits of firing Jones for
unprotected reasons. It simply noted that Exclusive Jets’ inability to explain why it had
never disciplined Jones, retrained or otherwise corrected him, or tried reassigning him to
another crew rotation, indicated that Exclusive Jets had not shown—by clear and
convincing evidence—that it would have fired Jones for those valid reasons.
D.
Having concluded that the ARB properly affirmed the ALJ’s conclusions regarding
liability, we turn to damages. Exclusive Jets argues that the agency applied the incorrect
legal standard to Jones’s duty to mitigate damages. We agree, so we vacate and remand for
further proceedings.
Jones’s ability to claim back pay is limited by his duty to mitigate damages. See
Brady, 753 F.2d at 1273. To fulfill this duty, a claimant “must exercise reasonable diligence
in finding other suitable employment.” Id. at 1277 (cleaned up). Then, they “must also use
reasonable diligence to maintain any suitable employment which is secured.” Id. An
employer has the burden of proving that a terminated employee “failed to exercise such
diligence in seeking employment.” Id. at 1274.
15 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 16 of 17
The ARB, however, applied a higher standard, requiring an employer to show that
“the employee’s misconduct is gross or egregious,” or that “it constitutes a willful violation
of company rules” for a termination stemming from that conduct to toll back-pay liability.
J.A. 3986. The ARB pointed to this Court’s statements that “an employee who willfully
loses employment by engaging in deliberate or gross misconduct is not entitled to backpay
for a resulting earnings loss.” N.L.R.B. v. Pepsi Cola Bottling Co. of Fayetteville, 258 F.3d
305, 311 (4th Cir. 2001) (cleaned up). But it misunderstands that precedent. Although gross
or deliberate misconduct is sufficient to show a failure to mitigate, it is not a necessary
showing. Indeed, we have explicitly rejected a “narrow” standard that would deny back
pay “only to those whose discharges result from wanton, or wilful, deliberate, or intentional
behavior.” Brady, 753 F.2d at 1277.
In response, the Department of Labor and Jones argue that Brady articulated the
standard for Title VII but that Aviation Reform Act claims are different. We disagree. Title
VII’s duty to mitigate, though enshrined in statutory language, is “rooted in an ancient
principle” of the law of damages that “requires the claimant to use reasonable diligence in
finding other suitable employment.” Ford Motor Co. v. EEOC, 458 U.S. 219, 231 (1982).
That principle applies equally to Title VII and the Aviation Reform Act.
Thus, the ARB erred when it required Exclusive Jets to show that Jones engaged in
gross or egregious misconduct before it would hold Jones to a duty to mitigate his damages.
Even so, “[a]dministrative adjudications are subject to the same harmless error rule
that generally applies to civil cases.” Sea “B” Mining, 831 F.3d at 253. For example, we
have held that the erroneous application of a clear and convincing standard, rather than a
16 USCA4 Appeal: 25-1190 Doc: 76 Filed: 04/30/2026 Pg: 17 of 17
preponderance of the evidence standard, was harmless because the agency concluded that
there was “no evidence” to meet either burden. Downey v. U.S. Dep’t of the Army, 685 F.
App’x 184, 191 n.6 (4th Cir. 2017) (emphasis omitted).
We cannot find harmlessness here, however, because the ARB only concluded that
substantial evidence supported the ALJ’s determination that Jones “did not engage in gross
or egregious misconduct, nor a willful violation of company rules.” J.A. 3987. It did not
separately analyze whether Exclusive Jets had met its burden to demonstrate that Jones
failed to exercise reasonable diligence in seeking employment after his termination. The
agency may well reach the same conclusion under the proper standard, but we will vacate
and remand for it to decide the matter in the first instance.
IV.
In sum, we conclude that the ARB properly affirmed the ALJ’s findings and
conclusions as to liability, and thus we deny that portion of Exclusive Jets’ petition for
review. But because we conclude that the ARB applied the incorrect legal standard when
considering Jones’s duty to mitigate damages, we grant that portion of the petition for
review, vacate the portion of the ARB’s opinion concerning tolling Exclusive Jets’ back-
pay obligations, and remand for the agency to apply the correct standard.
PETITION GRANTED IN PART AND DENIED IN PART; VACATED IN PART AND REMANDED