FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

PAUL W. PARKER, as Personal 

Representative of the Estate of Curtis 

John Rookaird, 

Plaintiff-Appellant, 

 v. 

BNSF RAILWAY COMPANY, a 

Delaware corporation, 

Defendant-Appellee.

No. 22-35695

D.C. No.

2:14-cv-00176-

RAJ 

OPINION

Appeal from the United States District Court

for the Western District of Washington

Richard A. Jones, District Judge, Presiding

Argued and Submitted July 13, 2023

Seattle, Washington

Filed August 9, 2024

Before: Susan P. Graber, Ronald M. Gould, and Richard 

A. Paez, Circuit Judges.

Opinion by Judge Gould;

Dissent by Judge Graber
2 PARKER V. BNSF RAILWAY COMPANY

SUMMARY*

Federal Railroad Safety Act

The panel affirmed in part and vacated in part the district 

court’s judgment in favor of BNSF Railway Company in an 

action brought under the anti-retaliation provision of the 

Federal Railroad Safety Act by Curtis Rookaird through his 

estate representative Paul Parker. 

After a jury found in Rookaird’s favor, this court vacated 

the verdict and remanded for the district court to reconsider 

its partial summary judgment for Rookaird on the issue 

whether his performing an air-brake test had contributed to 

BNSF’s decision to terminate him. On remand, the district 

court conducted a bench trial on the issue and decided in 

BNSF’s favor. The district court found that BNSF had 

conceded that Rookaird’s refusal to stop performing the airbrake test contributed to its decision to discharge him, but 

the district court nonetheless concluded that BNSF was 

entitled to an affirmative defense by showing that the airbrake test “contributed very little” to its decision. 

The panel affirmed the district court’s evidentiary 

rulings, concluding that the district court did not abuse its 

discretion in excluding certain testimony designations and 

admitting BNSF’s comparator evidence. 

The panel concluded, however, that the district court’s 

application of the Federal Railroad Safety Act did not 

comply with the text of the statute, which prohibits the 

* This summary constitutes no part of the opinion of the court. It has 

been prepared by court staff for the convenience of the reader.
PARKER V. BNSF RAILWAY COMPANY 3 

discriminatory discharge of an employee due even “in part” 

to the employee’s refusal to violate or assist in violating a 

railroad safety law, rule, or regulation. Nor was the district 

court’s conclusion consistent with relevant case law. The 

panel held that BNSF needed to demonstrate by clear and 

convincing evidence not merely that it could have fired 

Rookaird absent his engaging in the protected activity, but 

rather that it would have fired Rookaird. The panel vacated 

the district court’s judgment and remanded for the district 

court to consider whether BNSF met its burden to prove that 

the company would have terminated Rookaird absent his 

refusal to stop performing the air-brake test, given that the 

test could not contribute even in part to a termination 

decision. 

Dissenting, Judge Graber wrote that the majority 

misread both the relevant statute and the district court’s 

decision. She wrote that the record amply supported the 

district court’s finding that BNSF proved its affirmative 

defense by presenting clear and convincing evidence that it 

would have fired Rookaird anyway, even if he had not 

engaged in the protected activity of testing the brakes. 

COUNSEL

Cyle A. Cramer (argued), William G. Jungbauer, and John 

D. Magnuson, Yaeger & Jungbauer Barristers PLC, Saint 

Paul, Minnesota; for Plaintiff-Appellant. 

David M. Morrell (argued) and Jacqueline M. Holmes, Jones 

Day, Washington, D.C.; Shelby B. Smith, Jones Day, 

Pittsburgh, Pennsylvania; Tim D. Wackerbarth, Callie A. 

Castillo, and Andrew G. Yates, Lane Powell PC, Seattle, 

Washington; for Defendant-Appellee.
4 PARKER V. BNSF RAILWAY COMPANY

OPINION

GOULD, Circuit Judge:

Curtis Rookaird, through his estate representative Paul 

Parker, challenges his termination from BNSF Railway 

Company (BNSF) under the anti-retaliation provision of the 

Federal Railroad Safety Act (FRSA), 49 U.S.C. § 20109(d). 

After a jury found in Rookaird’s favor, the Ninth Circuit 

vacated the verdict and remanded the case to the district 

court to reconsider its partial summary judgment for

Rookaird on the issue of whether his performing an air-brake 

test had contributed to BNSF’s decision to discharge him. 

Rookaird v. BNSF Ry. Co., 908 F.3d 451, 463 (9th Cir. 2018) 

(Rookaird I). On remand, the district court conducted a 

bench trial on the issue and decided in BNSF’s favor. The 

district court found that BNSF had conceded that Rookaird’s

refusal to stop performing the air-brake test contributed to its

decision to discharge Rookaird, but the court nonetheless

concluded that BNSF was entitled to an affirmative defense 

by showing that the air-brake test “contributed very little” to 

BNSF’s decision. Rookaird appeals, contending that the 

district court erred in its analysis of BNSF’s affirmative 

defense and in certain evidentiary rulings.

We conclude that the district court’s application of the 

FRSA does not comply with the text of the statute, which 

prohibits the discriminatory discharge of an employee due 

even “in part” to the employee’s refusal to violate or assist 

in violating a railroad safety law, rule, or regulation. 49 

U.S.C. § 20109(a)(2). Nor is the district court’s conclusion 

consistent with relevant case law, including our reasoning in 

a prior case that, under the burden-shifting framework

required for FRSA cases, “[a plaintiff] would be entitled to 
PARKER V. BNSF RAILWAY COMPANY 5

relief even if [the protected activity] played only a very small 

role in [the employer’s] decision-making process.” Frost v. 

BNSF Ry. Co., 914 F.3d 1189, 1197 (9th Cir. 2019) (citing 

Rookaird I, 908 F.3d at 461). BNSF needed to demonstrate

by clear and convincing evidence not merely that it could

have fired Rookaird absent his engaging in the protected 

activity, but rather that BNSF would have fired Rookaird. 49 

U.S.C. § 42121(b)(2)(B)(ii); 29 C.F.R. § 1982.104(e)(4); see

Brousil v. U.S. Dep’t of Labor, Admin. Review Board, 43 

F.4th 808, 812 (7th Cir. 2022) (citing Speegle v. Stone & 

Webster Constr., Inc., ARB No. 13-074, 2014 WL 1870933, 

at *7 (Dep’t of Labor Admin. Review Bd. Apr. 25, 2014)). 

An FRSA affirmative defense is a “steep burden,” see 

Araujo v. New Jersey Transit Rail Operations, Inc., 708 F.3d 

152, 162 (3d Cir. 2013), particularly when a district court

finds that an employer concedes that the protected activity 

contributed to the decision to terminate the employee who 

engaged in it. 

We have jurisdiction under 28 U.S.C. § 1291. We affirm 

the district court’s evidentiary rulings, and we vacate and 

remand the affirmative defense issue for further proceedings 

consistent with this opinion.

I. FACTS AND PROCEDURAL HISTORY

A. Rookaird’s Tenure at BNSF

1. On and Before February 23, 2010

Curtis Rookaird began working for BNSF, a national 

freight train operator, in 2004. Before February 23, 2010, 

Rookaird did not have a disciplinary record. He began his 

shift at 2:30 p.m. on February 23, 2010, working on a threeperson “switcher” crew at BNSF’s Swift depot with engineer 

Peter Belanger and brakeman Matthew Webb. Rookaird, as 
6 PARKER V. BNSF RAILWAY COMPANY

a conductor, was in charge of the crew. The crew was 

supposed to take a van from Swift to Ferndale, and then take 

train cars back to Custer, where his crew would move 42 

railway cars onto storage tracks. The crew was then 

expected to take a van to Cherry Point to service BNSF 

customers. The crew initially encountered an approximately

two-hour delay while waiting for the paperwork they needed 

to start the day. At Custer, before moving the cars to storage, 

Rookaird and his crew performed an air-brake safety test. 

This test took around twenty to forty minutes to complete.

Rookaird and his crew performed this air-brake test in 

accordance with the company’s standard operating

procedures and recent changes to local processes. BNSF 

train crews nationwide perform routine air-brake tests—

sometimes called “air tests”—on a daily basis. Air-brake

tests typically take twenty to twenty-five minutes to 

complete. BNSF had started conducting remote audits to 

ensure that employees were performing air-brake tests. On 

February 11, weeks before Rookaird was at Custer with his 

crew, BNSF implemented a new plan to manage the railway

in the Cherry Point area more efficiently by moving the 

starting point for its switcher crews from Bellingham to

Swift. The new plan decreased employees’ hours, but did 

not propose reducing or eliminating air-brake tests to gain 

efficiency.

BNSF, however, encountered less efficient operations 

that month while implementing the new plan, with train cars

often sitting idle for longer than usual. BNSF Assistant 

Superintendent Stuart Gordon testified during the bench trial 

that complications were happening at that time, resulting in 

delays. Trainmaster Dan Fortt, who reported to Gordon,

testified that BNSF was then “days behind” on their service 

commitments, calling the place an “operational nightmare.” 
PARKER V. BNSF RAILWAY COMPANY 7

Nonetheless, the BNSF company rules stated that, if an 

employee was in doubt about whether to perform an airbrake test, he should “take the safe course.”

Fortt, headquartered in Canada and then serving BNSF

as a front-line supervisor, radioed Rookaird’s crew on 

February 23 while they were conducting the air-brake test. 

He asked them why they were doing it. Fortt commented: 

“I’m not from around here, and I don’t know how you guys 

do anything. But where I’m from, we don’t have to air test 

the cars.” Fortt had the authority to instruct the crew more 

explicitly to stop the air-brake test, but he did not do so. The 

crew completed the test.

Gordon, who supervised Fortt, had told Fortt to question 

Rookaird about why the crew was performing an air-brake

test. Gordon objected that Rookaird’s crew’s performance 

of the test was unnecessary. Gordon concluded that the crew 

was inefficient that day because performing the air-brake test

had delayed the operation. When later asked during his 

testimony which part of the job the crew was not doing 

efficiently, Gordon urged: “An air test, I’m telling you.”

When asked for any other basis for the crew’s inefficiency,

Gordon did not mention any other specifics.

Rookaird’s crew started moving the cars into storage. 

The crew got another call from Fortt, this time asking how 

much longer they would take to finish storing the cars. It 

was around 7:30 p.m., and Rookaird estimated they would 

take another hour or two. At Gordon’s direction, Fortt told 

Rookaird’s crew to pack up and report back to the Swift 

depot because another crew was going to finish the job. 

Gordon called Rookaird’s crew back in part to question them

as to why they performed the air-brake test. Fortt agreed that 

Rookaird’s crew was taking too long to do their job. Fortt
8 PARKER V. BNSF RAILWAY COMPANY

also thought that the air-brake test was unnecessary and 

“contributing” to slowing the process down. Fortt was not 

aware of any other reasons for the crew’s delay.

Back at the Swift depot, Gordon told Rookaird and the 

crew to “tie up.” Gordon claimed that he did not then plan 

to pursue disciplinary action against Rookaird or the crew. 

Rookaird completed his tie-up timeslip at 8:02 p.m. but did 

not sign it. Rookaird went to the breakroom, where he had 

a heated exchange with another employee, Ron Krich.

Gordon believed he overheard Rookaird encouraging Krich 

to “slow down,” suggesting an intentional effort to log more 

hours and earn overtime pay, though ultimately no one 

testified to having heard Rookaird use those exact words. 

Gordon came over and told Rookaird to leave. When 

Rookaird did not leave, Gordon again told Rookaird to go 

home. Rookaird then left. Rookaird reported that his final 

off-duty time for that day was 8:30 p.m., within the thirtyminute grace period permitted by BNSF’s policies and 

practices.

Gordon immediately conferred with Fortt and then

referred Rookaird’s crew for discipline in an e-mail to 

Gordon’s immediate supervisor, Jeff Beck, as well as to the 

General Manager of the Northwest Division, Doug Jones,

and investigating officer Robert Johnson. Gordon testified 

that he told these individuals that Rookaird’s crew did an airbrake test that day “that wasn’t necessary.”

2. The Investigation & Rookaird’s Termination

On February 26, 2010, BNSF sent Rookaird a letter 

alerting him that BNSF was investigating his actions on 

February 23, 2010. The letter informed Rookaird that BNSF 

was investigating him for: (1) failure to work efficiently,

(2) dishonesty in reporting his off-duty time, (3) failure to 
PARKER V. BNSF RAILWAY COMPANY 9

provide a signed tie-up timeslip, and (4) failure to comply 

with instructions when specifically told to leave the 

property. BNSF justified its discipline based on its Policy 

for Employee Performance and Accountability (PEPA). The 

PEPA established the consequences BNSF could impose for 

each type of rule violation. The list included aggravated 

offenses for which BNSF had the option to terminate an 

employee based on a single violation. These aggravated 

offenses included gross dishonesty and insubordination.

Johnson conducted a twelve-hour investigation hearing

on March 12, 2010. Rookaird had union representation

present at the hearing. Johnson did not call Krich as a 

witness to testify about whether Rookaird talked to him in 

the breakroom about a “slow down.”

Johnson sent the transcript to the director of employee 

performance James Hurlburt, as well as to Doug Jones, who 

had the decision-making authority to discharge Rookaird. In 

an e-mail dated March 17, 2010, Johnson, as the 

investigating officer, wrote to Hurlburt and Jones: “I am not 

going to tell you this crew was the only crew that played the 

slowdown game. However, I will tell you that this crew 

made a fatal mistake and we have to make an example out of 

them.” Jones later testified that Johnson’s email had 

“passion associated with it” and “a lot of emotion put in 

there.”

Hurlburt recommended that Jones dismiss Rookaird. 

Jones agreed, concluding that Rookaird had committed rule 

violations that merited immediate dismissal. Jones testified 

at the bench trial that Rookaird could not have been 

dismissed for failure to work inefficiently, because he did 

not have any prior record of discipline for that. Jones did 
10 PARKER V. BNSF RAILWAY COMPANY

testify, however, that Rookaird’s encouraging Krich to slow 

down contributed to Jones’s decision.

BNSF terminated Rookaird on March 19, 2010, effective 

immediately. BNSF’s stated reasons for terminating 

Rookaird echoed those given in the investigation notice 

letter, all based solely on what happened on February 23: 

(1) “failure to work efficiently,” (2) “dishonesty when 

reporting [his] off duty time,” (3) “failure to provide a signed 

[] [t]ie-up timeslip,” and (4) “failure to comply with 

instructions when told to leave the property. . . .” BNSF also 

disciplined the two other crew members who were with 

Rookaird that day, Webb and Belanger, for their failure to 

work efficiently. Webb and Belanger received a thirty-day 

suspension and probation.

B. Procedural History

Rookaird sued BNSF in 2014 under the anti-retaliation 

provision of the FRSA, 49 U.S.C. § 20109(a)(2), (d), 

alleging that BNSF discharged him in part for his refusal to 

stop the air-brake test. BNSF claimed that it would have 

fired Rookaird even if he had not engaged in the air-brake 

test. The district court entered a partial summary judgment 

in favor of Rookaird, concluding that the protected activity 

was a contributing factor in his termination. The district 

court found that disputed issues of material fact remained as 

to whether Rookaird had engaged in an activity protected by 

the FRSA and whether BNSF could prove its affirmative 

defense. Rookaird I, 908 F.3d at 455. The case proceeded 

to a jury trial in 2016 on these issues. The jury returned a 

verdict for Rookaird and awarded him more than $1 million 

in damages. Id.

On BNSF’s first appeal, we affirmed in part that 

Rookaird had engaged in a protected activity when he
PARKER V. BNSF RAILWAY COMPANY 11

refused to stop the air-brake test. Id. at 455–59.

1 We

reversed in part, however, after concluding that, under the 

relevant burden-shifting framework, the district court had 

improperly conflated Rookaird’s prima facie and 

substantive showings. Id. at 459. We concluded instead that 

Rookaird was not entitled to summary judgment on the 

contributing-factor element at the substantive stage of the 

proceedings. Id. at 459–62. We vacated the jury verdict and 

remanded. Id. at 463. We expressed no view on how the 

district court should handle the issue of BNSF’s affirmative 

defense on remand. Id.

On remand, the district court determined that three 

triable issues remained: (1) the contributing-factor element 

of the substantive stage of Rookaird’s case, (2) BNSF’s 

affirmative defense, and (3) damages. The court set a jury 

trial for October 12, 2021.

On September 11, 2021, Rookaird passed away. Paul 

Parker, as the personal representative of Rookaird’s estate, 

substituted for Rookaird as the plaintiff. The parties then 

stipulated to a bench trial.

The district court held a four-day bench trial in October 

2021. The district court confronted two critical evidentiary 

issues relating to the designation of certain witnesses’ prior 

testimony and comparator evidence. We discuss these

evidentiary issues in turn, and then turn to the district court’s 

decision.

1 In our analysis, we noted that sufficient evidence supported the jury’s 

finding that Rookaird refused “in good faith” to violate a railroad safety 

rule or regulation by completing the air-brake test. Rookaird I, 908 F.3d 

at 456.
12 PARKER V. BNSF RAILWAY COMPANY

1. Testimony Designations

Plaintiff’s counsel sought to designate the previous trial 

or deposition testimony of seventeen witnesses, including 

Rookaird’s testimony. At a pretrial conference, the district 

court said that it would “permit the testimony to come in as 

[plaintiff’s counsel] presents, if he believes that that’s the 

way he wants to present that portion of his case.” At the start 

of the bench trial, the district court indicated that the 

designated testimony “will be reviewed and considered,” but 

not read into the record. The district court ordered plaintiff’s 

counsel to file a declaration about the specific efforts that he 

had taken to make witnesses available for live testimony 

during the bench trial. Plaintiff’s counsel described 

challenging circumstances with respect to witnesses who 

had died, retired, lived out of state, or had developed mental 

health problems that inhibited them from testifying. 

Ultimately, the district court accepted the designated 

testimony from many prior witnesses including Rookaird, 

Hurlburt, Johnson, Webb, Belanger, and Beck. The district 

court denied the designations for other remaining witnesses, 

including Krich and Rookaird’s wife.

2. Comparator Evidence

BNSF had sent Rookaird’s counsel a spreadsheet from

BNSF’s internal database with limited descriptions of other

employees’ disciplinary records. The district court granted 

Rookaird’s request for more detailed information and 

directed BNSF to produce relevant specific information 

about twelve comparators that were selected by Rookaird. 

BNSF provided Rookaird with information about three 

employees who had no prior disciplinary record and who 

were dismissed for “willful dishonesty,” including

falsification of their tie-up time records, among other 
PARKER V. BNSF RAILWAY COMPANY 13

violations. BNSF’s records revealed that other employees 

received only a reminder, warning, suspension, or other 

minor discipline for similar infractions.

3. The District Court’s Decision

The district court issued its Findings of Fact and 

Conclusions of Law on March 28, 2022. In addition to the 

facts stated above, the district court made a factual finding 

of particular note: “BNSF concedes that Mr. Rookaird’s 

conducting of the air test contributed to the crew’s supposed 

inefficiency and delay.” The district court based this finding 

on multiple grounds: Jones’s admission that he had fired 

Rookaird in part because of the delays that occurred that day, 

which included a twenty-five-minute delay for the air test;

Gordon’s admission that Rookaird’s crew was being 

inefficient in part due to the air-brake test; and Fortt’s 

admission that the air-brake test contributed to slowing down 

the crew’s process.

In its legal conclusions, the district court relied on this

factual finding to conclude: “BNSF concedes that the crew’s 

inefficiency was partly caused by Mr. Rookaird’s decision 

to conduct an air test—a test that BNSF managers thought 

was unnecessary to conduct in the first place.” The court 

continued: “Because Mr. Rookaird was fired for his 

inefficiency and because the inefficiency was partly caused 

by the protected activity of refusing to stop the air test, the 

Court concludes that the air test ‘tend[ed] to affect in [some] 

way the outcome of [BNSF’s] decision’ to fire Mr. 

Rookaird.” And because refusing to stop the air-brake test 

“affected” BNSF’s decision to terminate Rookaird, it was a 

“contributing factor” in his termination. The district court 

further concluded that Rookaird proved his substantive 
14 PARKER V. BNSF RAILWAY COMPANY

burden to show that refusal to stop conducting the air-brake 

test was a contributing factor in his dismissal.

The district court nonetheless concluded that BNSF met 

its burden to prove its affirmative defense—that is, to show 

by clear and convincing evidence that, absent Rookaird’s 

refusal to stop the air-brake test, BNSF would have still fired 

him for “many reasons unrelated to his inefficiency.” The 

district court reasoned: “[T]hough the air test was a 

contributing factor in Mr. Rookaird’s termination, the Court 

concludes that the test contributed very little.” 

The district court stressed that the air-brake test only 

took twenty to forty minutes of the crew’s five-and-a-half 

hours of work, and no BNSF officer explicitly commanded

Rookaird to stop the test. The district court’s conclusion 

rested on Rookaird’s inaccurate and unsigned February 23 

tie-up timeslip, Rookaird’s repeated refusal to leave work 

despite Gordon’s two orders telling him to stop work, and 

Rookaird’s exchange with Krich. The district court further 

pointed to the routine nature of the air-brake test, combined 

with the lesser discipline given to Rookaird’s two crewmates 

Webb and Belanger. From this, the district court concluded 

that BNSF, having satisfied its affirmative defense, was not 

liable for unlawful retaliation under the FRSA. Plaintiff’s 

counsel moved to alter or amend the judgment, or in the 

alternative for a new trial. The district court denied the 

motion on August 5, 2022.

Rookaird timely appealed. On appeal, he contends that 

the district court erred in concluding that BNSF established 
PARKER V. BNSF RAILWAY COMPANY 15

its affirmative defense in light of FRSA law and the record.2 

Rookaird also argues that the district court’s evidentiary 

rulings, which excluded certain testimony offered by 

plaintiffs and admitted evidence offered by BNSF 

concerning BNSF’s new comparator evidence, constitute 

reversible error.

II. STANDARD OF REVIEW

After a bench trial, we review a district court’s 

conclusions of law de novo, and we review its findings of 

fact for clear error. See Yu v. Idaho State Univ., 15 F.4th 

1236, 1241–42 (9th Cir. 2021). We review de novo the legal 

inferences that a district court made while applying the law 

to the facts. See Suzy’s Zoo v. Comm’r, 273 F.3d 875, 878 

(9th Cir. 2001). We review evidentiary rulings for abuse of 

discretion and only reverse an evidentiary ruling for 

prejudicial error. Wagner v. Cnty. of Maricopa, 747 F.3d 

1048, 1052 (9th Cir. 2013).

III. DISCUSSION

A. The Text and History of the FRSA

Construction began on the nation’s first commercially 

chartered railway in 1828 when Charles Carroll, the last 

surviving signer of the Declaration of Independence, laid the 

first stone in Baltimore Harbor.3 In 1970, more than 140 

years later, Congress enacted the FRSA as its first 

2 Rookaird also appeals the district court’s denial of his Fed. R. Civ. P. 59 

motion to alter or amend the judgment, or in the alternative for a new 

trial. In view of our decision, stated hereafter, we need not reach 

Rookaird’s challenge to the denial of his Rule 59 motion.

3 Library of Congress, Today in History – February 28, LOC Digital 

Collections, at https://perma.cc/Z6SR-6TFG.
16 PARKER V. BNSF RAILWAY COMPANY

comprehensive railroad safety law.4 The FRSA aims “to 

promote safety in every area of railroad operations and 

reduce railroad-related accidents and incidents,” affecting

railroad workers, passengers, and the general public. See 49 

U.S.C. § 20101. Important safety measures include the airbrake tests that railway employees must perform. See 

Rookaird I, 908 F.3d at 456. A problem with a train’s airbrake system can contribute to a crash or derailment, 

resulting in hazardous material spills, fatalities, or other 

issues that can gravely impact the lives of persons on the 

train or living nearby.

5 A train that cannot stop safely 

threatens disaster for railroad crews and the general public. 

To encourage accurate reports about railroad safety, 

Congress amended the FRSA, first in 1980 and again in 

2007, to add anti-retaliation measures ensuring that 

employees could report their safety concerns without fear. 

See Araujo, 708 F.3d at 156–57, n.3 (citing H.R. Rep. No. 

110-259, at 348 (2007) (Conf.Rep.), as reprinted in 2007 

U.S.C.C.A.N. 119, 181); Lee v. Norfolk S. Ry. Co., 802 F.3d 

626, 629–30 (4th Cir. 2015) (citing the Federal Railroad 

Safety Authorization Act of 1980, Pub.L. No. 96-423, § 10, 

4 See Frank J. Mastro, Preemption is Not Dead: The Continued Vitality 

of Preemption Under the Federal Railroad Safety Act Following the 

2007 Amendment to 49 U.S.C. § 20106, 37 Transp. L. J. 1, 2 (2010).

5 See Daniel Gilbert and Tom McGinty, Brake-Related Failures Dog 

Freight Railroads, Wall St. J., July 16, 2013, at https://perma.cc/27ELEM6L; see also CSX Train Derailment with Hazardous Materials 

Release, Hyndman, Pennsylvania, August 2, 2017 vii, 12 (N.T.S.B. Nov. 

23, 2020), at https://perma.cc/5U7Q-T2EP; Katherine Shaver, Bad 

Brakes Caused Derailment, Wash. Post, Mar. 6, 2002, at 

https://perma.cc/XMD3-3Z3L; Ian Austen, A Decade After a Deadly 

Derailment, Some Wonder if Canada’s Railroads Are Safe, N.Y.Times,

Feb. 24, 2023, at A12.
PARKER V. BNSF RAILWAY COMPANY 17

94 Stat. 1811 (1980); H.R. Conf. Rep. No. 110-259, at 348 

(2007), as reprinted in 2007 U.S.C.C.A.N. 119, 180–81); see 

also Christopher W. Bowman, Whistleblower Protections of 

the Federal Rail Safety Act: An Overview, 8 Wm. Mitchell 

J. L. & Prac. 1, 1 (June 2015).

Under the FRSA as amended:

A railroad carrier . . . may not discharge, . . . 

reprimand, or in any other way discriminate 

against an employee if such discrimination is 

due, in whole or in part, to the employee’s 

lawful, good faith . . . refus[al] to violate or 

assist in the violation of any Federal law, rule, 

or regulation relating to railroad safety . . . .

49 U.S.C. § 20109(a)(2).

To prevail on an FRSA claim, the plaintiff must prove 

four elements: (1) the plaintiff engaged in an FRSAprotected activity; (2) the employer knew that the plaintiff 

engaged in that protected activity; (3) the plaintiff suffered 

an unfavorable personnel action; and (4) the protected 

activity “was a contributing factor in the unfavorable 

personnel action.” Rookaird I, 908 F.3d at 455 (citation 

omitted). The “contributing factor” element is the only 

element at issue in this appeal. To prove these four elements, 

a plaintiff must meet the burdens of proof set forth in 49 

U.S.C. § 42121(b)(2)(B), which provides the rules and 

procedures governing whistleblower cases under the 

Wendell H. Ford Aviation Investment and Reform Act for 

the 21st Century (AIR-21). 49 U.S.C. § 20109(d)(2)(A)(i)

(incorporating section 42121(b)(2)(B) by reference); see 

also Araujo, 708 F.3d at 156–57. As clarified by our earlier 

opinion, the AIR-21 standard sets forth a burden-shifting 
18 PARKER V. BNSF RAILWAY COMPANY

framework that contains two distinct stages: the prima facie

showing and the substantive showing. 49 U.S.C. 

§ 42121(b)(2)(B); Rookaird I, 908 F.3d at 460. In each 

stage, if a plaintiff makes the required showing, the burden 

shifts to the respondent, such that each of the two stages 

contains two steps.

At the prima facie stage, the plaintiff must first establish

the existence of facts sufficient to raise an inference that the 

protected activity was a “contributing factor” in the 

unfavorable personnel action. 49 U.S.C. 

§ 42121(b)(2)(B)(i); 29 C.F.R. § 1982.104(e)(1)–(3). 

Second, the employer then has the burden to demonstrate, by 

clear and convincing evidence, that it “would have taken the 

same unfavorable personnel action in the absence of that 

behavior.” 49 U.S.C. § 42121(b)(2)(B)(ii); 29 C.F.R. 

§ 1982.104(e)(4).

If the analysis proceeds to the substantive stage, the first 

step of the substantive analysis requires the plaintiff to 

demonstrate by a preponderance of the evidence that the 

protected activity was a “contributing factor” in the 

unfavorable personnel action. 49 U.S.C. 

§ 42121(b)(2)(B)(iii); 29 C.F.R. § 1982.109(a). If the 

plaintiff makes this showing, the second step of the 

substantive analysis again shifts the burden to the employer, 

allowing the employer to present an affirmative defense. 

“[I]f the respondent-employer demonstrates by clear and 

convincing evidence that the employer would have taken the 

same unfavorable personnel action in the absence of that 

behavior,” the plaintiff cannot prevail. 49 U.S.C. 

§ 42121(b)(2)(B)(iv); 29 C.F.R. § 1982.109(b); see also

Rookaird I, 908 F.3d at 454, 459–60.
PARKER V. BNSF RAILWAY COMPANY 19

While McDonnell Douglas has provided courts with a 

default burden-shifting scheme to analyze discrimination

claims, the FRSA burden-shifting framework is “much more 

protective of plaintiff-employees than the McDonnell 

Douglas framework,” because a claimant need only show 

that his protected activity was “a contributing factor” in any 

disciplinary action or termination, “not the sole or even 

predominant cause.” Araujo, 708 F.3d at 158 (citing 49 

U.S.C. § 42121(b)(2)(B)(ii)); see also Greatwide Dedicated 

Transp. II, LLC v. U.S. Dep’t of Labor, 72 F.4th 544, 554

(4th Cir. 2023) (quoting Formella v. U.S. Dep’t of Labor, 

628 F.3d 381, 389 (7th Cir. 2010) (internal citation omitted))

(the AIR-21 standard is “more favorable to the complaining 

employee”); see also McDonnell Douglas Corp. v. Green, 

411 U.S. 792 (1973).

As the Supreme Court recently stated, “the contributingfactor burden-shifting framework is meant to be more lenient 

than most” employment discrimination burden-shifting 

frameworks in that it “is not as protective of employers as a 

motivating-factor framework.” Murray v. UBS Securities, 

LLC, 601 U.S. 23, 35, 39 (2024). “That is by design.” Id. at 

39. “Congress has employed the contributing-factor 

framework in contexts where the health, safety, or wellbeing of the public may well depend on whistleblowers 

feeling empowered to come forward.” Id. We “cannot 

override that policy choice by giving employers more 

protection than the statute itself provides.” Id.

We turn to the district court’s analysis of the substantive 

stage of Rookaird’s claim followed by BNSF’s affirmative 

defense.
20 PARKER V. BNSF RAILWAY COMPANY

B. An FRSA Affirmative Defense at the Substantive 

Stage

1. Rookaird’s Protected Activity Was a Contributing 

Factor

At the outset, it is undisputed that Rookaird proved his 

substantive case by showing, by a preponderance of the 

evidence, that his refusal to stop conducting the air-brake test

was a contributing factor to BNSF’s decision to discharge 

him. See 49 U.S.C. § 42121(b)(2)(B)(iii); 29 C.F.R. 

§ 1982.109(a).

The incorporation of a contributing factor standard into 

the FRSA “reflects a judgment that ‘personnel actions 

against employees should quite simply not be based on 

protected [whistleblowing] activities’—not even a little bit.” 

Murray, 601 U.S. at 36–37 (quoting Marano v. Dep’t of 

Justice, 2 F.3d 1137, 1141 (Fed.Cir. 1993) (internal citation 

omitted)) (cleaned up). The FRSA prohibits discharge or 

reprimand due even “in part” to an employee’s lawful, good 

faith refusal to violate a railroad safety law, rule, or 

regulation. 49 U.S.C. § 20109(a)(2). It is well-established 

under the FRSA that “[a] ‘contributing factor’ includes ‘any 

factor, which alone or in connection with other factors, tends 

to affect in any way the outcome of the decision.’” Rookaird 

I, 908 F.3d at 461 (quoting Gunderson v. BNSF Ry. Co., 850 

F.3d 962, 969 (8th Cir. 2017)) (internal citation omitted).

The contributing factor standard was intended to 

overrule existing case law, which required a whistleblower 

to prove that his protected conduct was a “‘significant,’ 

‘motivating,’ ‘substantial,’ or ‘predominant’ factor in the 

adverse personnel action . . . .” Murray, 601 U.S. at 28 

(citation omitted). An FRSA contributing factor “may be 

quite modest.” Frost, 914 F.3d at 1197 (citing Rookaird I, 
PARKER V. BNSF RAILWAY COMPANY 21

908 F.3d at 461). “The Supreme Court has interpreted 

similar language as creating liability if the employee’s action 

causes ‘even the slightest’ influence on the employer’s 

decision.” Yowell v. Admin. Review Board, U.S. Dep’t of 

Labor, 993 F.3d 418, 424 (5th Cir. 2021) (quoting CSX 

Transp., Inc. v. McBride, 564 U.S. 685, 692, 695–99

(2011)).

The record plainly supports the district court’s 

conclusion that Rookaird’s refusal to stop the air-brake test 

contributed to his termination. The district court concluded, 

at the substantive stage, that Rookaird’s decision to proceed 

with the air-brake test “tend[ed] to affect in [some] way the 

outcome of [BNSF’s] decision” to fire Rookaird, because 

Rookaird was fired “in part” for his inefficiency on February 

23. The district court based its conclusion on the testimony 

of Jones, Gordon, and Fortt. Given the testimony evidence, 

as noted above, the district court concluded: “BNSF 

concedes that the crew’s inefficiency was partly caused by 

Mr. Rookaird’s decision to conduct an air test.” “Because 

Mr. Rookaird was fired for his inefficiency, . . . the air test 

‘tend[ed] to affect in [some] way the outcome of [BNSF’s] 

decision’ to fire Mr. Rookaird,” making the air-brake test a 

“contributing factor” under the FRSA. Cf. Rookaird I, 908 

F.3d at 461.

Under the FRSA, the district court’s contributing factor 

findings and conclusions affect BNSF’s ability to prove at 

the affirmative defense stage that it would have terminated 

Rookaird absent the air-brake test.

2. BNSF’s Affirmative Defense

Our review proceeds to the next and final step of the 

burden-shifting framework, which is our primary question in 

this appeal: whether BNSF proved, by clear and convincing 
22 PARKER V. BNSF RAILWAY COMPANY

evidence, that it would have taken the same unfavorable

action against Rookaird absent his refusal to stop the airbrake test. The district court concluded that, “though the air 

test was a contributing factor in Mr. Rookaird’s termination, 

. . . the test contributed very little.” Despite acknowledging 

that Rookaird’s refusal to stop the test contributed in part to 

the decision to terminate him, the district court nonetheless 

determined “that BNSF is not liable for unlawful retaliation 

under the [FRSA].” That conclusion can stand only if BNSF 

was entitled to its affirmative defense.

In the FRSA context, “[u]nder the AIR-21 standard, [a 

plaintiff] would be entitled to relief even if [the protected 

activity] played only a very small role in [the employer’s] 

decision-making process.” Frost, 914 F.3d at 1197. The 

final stage of the AIR-21 burden-shifting framework allows 

an employer to defeat a claim for unlawful retaliation under 

the FRSA if the employer proves, by clear and convincing 

evidence, that it would have taken the same unfavorable 

personnel action absent the protected activity. See 49 U.S.C. 

§ 42121(b)(2)(B)(iv); 29 C.F.R. § 1982.109(b); Rookaird I, 

908 F.3d at 454, 459–60. The clear and convincing standard 

is an “intermediate burden of proof” between a 

“preponderance of the evidence” and “proof beyond a 

reasonable doubt.” Araujo, 708 F.3d at 159 (citation 

omitted); see also OTR Wheel Eng’g, Inc. v. West Worldwide 

Servs., Inc., 897 F.3d 1008, 1020 (9th Cir. 2019) (internal 

citations omitted). The Supreme Court has described the 

“clear and convincing” standard as “highly probable,” such 

that the material offered “instantly tilt[s] the evidentiary 

scales” in the direction of the party providing the proof. 

Colorado v. New Mexico, 467 U.S. 310, 316 (1984) (cleaned 

up). In other words, an employer must meet a “steep burden” 

to prove an FRSA affirmative defense under the AIR-21 
PARKER V. BNSF RAILWAY COMPANY 23

framework. See Araujo, 708 F.3d at 162. The burden is 

steep for FRSA defendants because, unlike defendants under

other whistleblowing statutes that utilize the AIR-21 

framework, an FRSA employer cannot discharge an 

employee for his protected activity even “in part.” See 49 

U.S.C. § 20109(a).

We rely on the plain text of the FRSA and give the 

statute’s words their “ordinary meaning.” See Araujo, 708 

F.3d at 158 (cleaned up). “In part” ordinarily means relating 

to a portion or division of a whole, to some extent. See Part

& In Part, Oxford English Dictionary (2d ed. 1989). Put 

another way, “in part” means any amount greater than zero. 

We will not adopt a reading of the FRSA that renders any of 

its words as surplusage. See Rookaird, 908 F.3d at 466 

(cleaned up). The text of 49 U.S.C. § 20109(a) does not 

permit an employer to discharge an employee if that decision

is based, to any extent, on the employee’s engaging in the

protected activity. See Araujo, 708 F.3d at 158 (cleaned up).

Because the FRSA is the controlling statute, we hold 

that, in an FRSA action, the affirmative defense step in the 

substantive stage of the AIR-21 framework cannot disregard 

the FRSA’s original inquiry about whether unfavorable 

action was due “in part” to the employee’s engaging in a 

protected activity. 49 U.S.C. § 20109(a)(2). Because we 

rely on the language of the FRSA, we limit our holding to 

FRSA actions. While the existence of an affirmative defense 

means that an employer can defeat FRSA liability in some 

circumstances, an employer faces a “steep burden,” see 

Araujo, 708 F.3d at 162, particularly when the protected 

activity plays a part—however small—within the contours 

of the employer’s adverse personnel decision. An FRSA 

employer may still be able to prove an affirmative defense 

where a plaintiff shows only a correlation between the 
24 PARKER V. BNSF RAILWAY COMPANY

protected activity and adverse action, but this is less likely

where a factfinder determines that the protected activity 

caused an employer’s adverse action, even in part. This is

true because an employer’s grounds for an unfavorable

personnel action must be “independently significan[t]”—

necessary and sufficient—apart from the employee’s 

engagement in the protected activity. See Brousil, 43 F.4th 

at 812 (citing Speegle, ARB No. 13-074, 2014 WL 1870933, 

at *7). The employer cannot prevail unless it proves by clear 

and convincing evidence that the discriminatory action still 

would have occurred absent the protected activity. See id.; 

49 U.S.C. § 42121(b)(2)(B)(iv); 29 C.F.R. § 1982.109(b).

While applying the FRSA affirmative defense standard, 

the district court reasoned that BNSF could still prove its 

affirmative defense because Rookaird’s refusal to stop the 

air-brake test “contributed very little” to BNSF’s decision to 

terminate him. The proper inquiry, however, is not whether 

the protected activity “contributed very little” to the firing; 

the proper inquiry is whether BNSF would have fired 

Rookaird regardless of whether he had conducted an airbrake test. See 49 U.S.C. § 42121(b)(2)(B)(iv); 29 C.F.R. 

§ 1982.109(b). Under the FRSA, the protected activity 

cannot contribute even “in part” to the employer’s 

termination decision, so the FRSA affirmative defense 

standard needs to proceed with an analysis about whether 

and how the termination decision would have occurred 

absent the protected activity, given that the protected activity 

cannot contribute to the employer’s adverse action decision

even in part. See 49 U.S.C. § 20109(a)(2); cf. Frost, 914 

F.3d at 1197; Murray, 601 U.S. at 28, 35–37, 39 (citations 

omitted).

Because we have not had much occasion to interpret 

what clear and convincing evidence an employer would need 
PARKER V. BNSF RAILWAY COMPANY 25

to provide to meet its affirmative defense burden under the 

FRSA, we look to our precedent and that of our sister circuits

to discern what this district court and others should consider. 

As recognized by the Seventh Circuit in Brousil, the 

Administrative Review Board has provided “guiding 

factors” that factfinders can consider when deciding whether 

an employer would have taken the same adverse action 

against an employee absent any protected activity. Those 

factors include “how ‘clear’ and ‘convincing’ the 

independent significance is of the non-protected activity” 

and “the facts that would change in the ‘absence of’ the 

protected activity.” Cf. Brousil, 43 F.4th at 812 (citing 

Speegle, ARB No. 13-074, 2014 WL 1870933, at *7). Put 

another way, the FRSA requires the employer to prove what 

it “would have done,” not merely what it could have done. 

Cf. id. As such, the FRSA tasks an employer with proving a 

counterfactual scenario, such that the factual findings

“instantly tilt the evidentiary scales” in their direction. 

Colorado, 467 U.S. at 316.

When an employer presents circumstantial evidence to 

prove its FRSA affirmative defense, such evidence may

include a lack of temporal proximity between the nonprotected activity and the unfavorable action; a poor 

employee work history and disciplinary record; the 

consistent application of the employer’s policies; similarly 

situated comparators; and the appropriate proportionality of 

the unfavorable action to the basis for it. Cf. Brousil, 43 

F.4th at 812 (citing Speegle, ARB No. 13-074, 2014 WL 

1870933, at *7); Van Asdale v. Int’l Game Tech., 577 F.3d. 

989, 1003 (9th Cir. 2009) (holding, without reaching the 

burden-shifting stage, that the employee’s “positive record” 

could lead a reasonable factfinder to decide that the 

protected activity contributed to the termination).
26 PARKER V. BNSF RAILWAY COMPANY

To this end, an employer’s claim that the plaintiff was 

“technically in violation of written rules” does not meet the 

affirmative defense burden without proof that the employer 

consistently applied the same or similar policies to similarly 

situated comparator employees. See Araujo, 708 F.3d at 

162–63; see also Greatwide, 72 F.4th at 558 (rejecting 

FRSA affirmative defense without proof that employer 

consistently terminated employees for similar violations 

under a range of possible disciplines); BNSF Ry. Co. v. U.S. 

Dep’t of Labor, 816 F.3d 628, 640–41 (10th Cir. 2016)

(rejecting FRSA affirmative defense when employer did not 

prove that it fired employees for similar violations); Pan Am 

Ry. v. U.S. Dep’t of Labor, 855 F.3d 29, 37 (1st Cir. 2017) 

(rejecting FRSA affirmative defense when employer did not 

prove that dishonesty in other instances was “of a similar 

character”); Fresquez v. BNSF Ry. Co., 52 F.4th 1280, 1307–

08 (10th Cir. 2022) (rejecting FRSA affirmative defense 

when employer did not show consistent application of standalone dismissible policy); cf. Brousil, 43 F.4th at 812 (citing 

Speegle, ARB No. 13-074, 2014 WL 1870933, at *7); Kuduk 

v. BNSF Ry. Co., 768 F.3d 786, 793 (8th Cir. 2014) (agreeing 

that BNSF proved its affirmative defense after presenting 

“uncontroverted evidence that it consistently enforced this 

policy”).

What’s more, an employer’s “shifting explanations” for 

its discipline call into question whether it would have 

administered the same discipline absent the protected 

activity. See Vieques Air Link, Inc. v. U.S. Dep’t of Labor, 

437 F.3d 102, 110 (1st Cir. 2006); see also Greatwide, 72 

F.4th at 559; BNSF Ry. Co., 816 F.3d at 641; Weatherford 

U.S., L.P. v. U.S. Dept’ of Labor, 68 F.4th 1030, 1041 (6th 

Cir. 2023).
PARKER V. BNSF RAILWAY COMPANY 27

An FRSA plaintiff can further show an “overwhelming” 

case of FRSA retaliation by presenting evidence that the 

employer tried to dissuade him from engaging in the 

protected activity. See BNSF Ry. Co., 816 F.3d at 640 

(rejecting FRSA affirmative defense when supervisors tried 

to dissuade plaintiff from engaging in protected activity); cf. 

Araujo, 708 F.3d at 163.

Rookaird’s lack of disciplinary record, a tenuous offer of 

proof from BNSF that it applied its policies consistently to 

relevant comparators, and BNSF’s efforts to dissuade 

Rookaird from performing the air-brake test raise questions

about how BNSF could have proved that it would have 

terminated Rookaird absent the air-brake test in light of the 

district court’s finding that BNSF conceded that the airbrake test contributed to its decision to discharge Rookaird.

6 

Rookaird had no disciplinary history at BNSF before 

February 23, 2010, and BNSF provided no evidence that it 

had planned to terminate, investigate, or otherwise 

reprimand Rookaird before the events on February 23. 

BNSF showed that gross dishonesty and insubordination 

6 The non-protected activity and the adverse action occurred in close 

temporal proximity, as did the protected activity. See Brousil, 43 F.4th 

at 812 (citing Speegle, ARB No. 13-074, 2014 WL 1870933, at *7) 

(cleaned up); Van Asdale, 577 F.3d. at 1003 (quotation omitted); Vieques 

Air Link, 437 F.3d at 108–09 (concluding that the employer failed to 

prove by clear and convincing evidence that the employee’s protected 

activity was unconnected to the adverse personnel action where the 

action “followed almost immediately on the heels of reports [plaintiff] 

made about [] safety violations”); cf. BNSF Ry. Co., 816 F.3d at 639–41 

(rejecting FRSA affirmative defense where investigation and 

termination commenced within a month of the protected activity). 

Because Rookaird’s protected and non-protected activity both occurred 

proximate to his termination, this factor may not counsel strongly one 

way or the other toward BNSF’s affirmative defense.
28 PARKER V. BNSF RAILWAY COMPANY

gave adequate stand-alone bases for dismissal after a single 

violation, but dismissal was discretionary and not a 

mandatory consequence for either violation. To show the 

consistent application of its policies, BNSF relied on one 

case with three comparators who were dismissed for willful 

dishonesty in their tie-up slips, but BNSF only notified

Rookaird that the company was investigating and 

terminating him for “dishonesty,” not “willful” or “gross”

dishonesty.

In any event, the district court did not base its 

conclusions on these comparators; it only considered that 

BNSF suspended and placed on probation the other two 

members of Rookaird’s crew for their failure to work 

efficiently on February 23. But Rookaird’s fellow crewmen 

make for poor comparators when they may very well have 

been impermissibly reprimanded for the same protected 

activity as Rookaird. The district court did not base its 

decision on BNSF showing comparators who were fired for 

insubordination. Rookaird’s supervisors, Fortt and Gordon, 

both tried to dissuade Rookaird from performing the airbrake test. Gordon concluded that the air-brake test delayed 

the crew and recalled the crew from their shift based on 

asserted inefficiency, and he did not state any other reason 

to believe that the crew worked inefficiently.

When we consider the propriety of an FRSA affirmative 

defense, we ask whether a district court considered such 

factors with the understanding that the protected activity 

cannot contribute to the employer’s adverse action decision 

even in part. See 49 U.S.C. § 20109(a)(2); 49 U.S.C. 

§ 42121(b)(2)(B)(iv); 29 C.F.R. § 1982.109(b). See, e.g.,

Araujo, 708 F.3d at 162–63; Greatwide, 72 F.4th at 558–60; 

BNSF Ry. Co., 816 F.3d at 640–41; Pan Am Ry., 855 F.3d at 

37; Fresquez, 52 F.4th at 1307–08; Weatherford U.S., L.P., 
PARKER V. BNSF RAILWAY COMPANY 29

68 F.4th at 1041; cf. Brousil, 43 F.4th at 812 (citing Speegle, 

ARB No. 13-074, 2014 WL 1870933, at *7); Kuduk, 768 

F.3d at 793.

We vacate and remand the affirmative defense issue for 

the district court to consider whether BNSF met its burden

to prove that the company would have terminated Rookaird 

absent his refusal to stop performing the air-brake test, given 

that the air-brake test cannot contribute even in part to a 

termination decision.

C. Evidentiary Rulings

Finally, Rookaird appeals two categories of evidentiary 

rulings: (1) the exclusion of certain testimony designations;

and (2) the admission of BNSF’s comparator evidence.

Under our abuse of discretion standard, we will not 

reverse an evidentiary ruling unless the decision is “beyond 

the pale of reasonable justification under the circumstances.” 

Boyd v. City and Cnty. of San Francisco, 576 F.3d 938, 943 

(9th Cir. 2009) (quoting Harman v. Apfel, 211 F.3d 1172, 

1175 (9th Cir. 2000)). In addition, “[a] party seeking 

reversal for evidentiary error must show that the error was 

prejudicial, and that the verdict was ‘more probably than not’ 

affected as a result.” Id. (quoting McEuin v. Crown Equip. 

Corp., 328 F.3d 1028, 1032 (9th Cir. 2003)) (cleaned up); 

see also Wagner, 747 F.3d at 1052.

Regarding the testimony designations, plaintiff’s 

counsel argues that he relied upon prior assurances from the 

district court that such evidence would be permitted. The 

district court, however, had said that it would only consider 

admitting such evidence whenever plaintiff’s counsel 

presented it, without previously ruling that any designation 

would be admitted. Plaintiff’s counsel also delayed the 
30 PARKER V. BNSF RAILWAY COMPANY

presentation of his deposition designations and his 

explanation of witness unavailability that might have

justified admitting the deposition testimony. The district 

court appropriately weighed the probative value of these 

designations and did so on a timeline that was reasonable 

given the timing of the proposed designations. Finally, the 

district court did admit the designated testimony of several 

of Rookaird’s key witnesses. The decision to exclude certain 

designated testimony by the district court is not “beyond the 

pale of reasonable justification under the circumstances.” 

See Boyd, 576 F.3d at 943 (quotation omitted). Moreover, 

plaintiff’s counsel does not identify how these rulings 

unfairly prejudiced his case, as he must. See id. (quotation 

omitted). We review evidentiary rulings only for abuse of 

discretion, and we conclude that the district court did not 

abuse its discretion in these rulings. See Wagner, 747 F.3d 

at 1052. 

Similarly, the district court’s admission of the 

comparator evidence late in the bench trial was reasonable 

based on when plaintiff’s counsel initially received this 

evidence and raised potential issues with it. As such, the 

district court did not abuse its discretion by admitting the

comparator evidence. See Boyd, 576 F.3d at 943 (quotation 

omitted); Wagner, 747 F.3d at 1052.

We affirm the district court’s evidentiary rulings.

IV. CONCLUSION

The FRSA prohibits an employer from taking an adverse 

action against an employee even “in part” based on their 

engagement with a protected activity. See 49 U.S.C. 

§ 20109(a); 49 U.S.C. § 42121(b)(2)(B); Frost, 914 F.3d at

1197; Araujo, 708 F.3d at 162; Murray, 601 U.S. at 28, 35–

37, 39. Because of this language, specific to the FRSA, the 
PARKER V. BNSF RAILWAY COMPANY 31

district court erred in its analysis of BNSF’s proffered 

affirmative defense when it reasoned that Rookaird’s airbrake test could contribute to BNSF’s decision to fire him so 

long as it was “very little.” 

We AFFIRM the district court’s evidentiary rulings, and

we VACATE and REMAND the judgment for further 

proceedings consistent with this opinion based on the record 

that the district court developed at the bench trial. 

Each party shall bear its own costs.

GRABER, Circuit Judge, dissenting: 

This is an easy appeal that warrants a short memorandum 

disposition affirming the district court. The only question 

before us is whether the court’s factual findings are clearly 

erroneous; they are not. The majority opinion has distorted 

the case beyond recognition by misreading both the relevant 

statute and the district court’s decision and by telling the 

district court to redo exactly what it already did right. 

Moreover, the majority opinion’s mangling of the law will 

affect a wide range of retaliation cases. I respectfully but 

emphatically dissent.

A. The District Court’s Analysis Was Sound.

The Wendell H. Ford Aviation Investment and Reform 

Act for the 21st Century (“AIR-21”) describes a 

straightforward, well-understood set of substantive 

provisions for proving claims of retaliation. The plaintiff 

bears an initial burden to prove that protected activity was 

one reason that contributed, even in small part, to dismissal. 

49 U.S.C. § 42121(b)(2)(B)(iii); Rookaird v. BNSF Ry. Co., 

908 F.3d 451, 454 (9th Cir. 2018). If the plaintiff meets that 
32 PARKER V. BNSF RAILWAY COMPANY

burden, the statute provides that the defendant has an 

affirmative defense: proving by clear and convincing 

evidence that “the employer would have taken the same 

unfavorable personnel action in the absence of that 

behavior.” Id. § 42121(b)(2)(B)(iv); Rookaird, 908 F.3d at 

460. In other words, even when protected activity 

contributed to a firing decision, the employer can “defeat the 

claim by demonstrating ‘by clear and convincing evidence 

that the employer would have taken the same unfavorable 

personnel action in the absence of [the protected activity].’” 

Frost v. BNSF Ry. Co., 914 F.3d 1189, 1197 (9th Cir. 2019) 

(alteration in original) (emphasis added) (quoting 49 U.S.C. 

§ 42121(b)(2)(B)(iv)). The employer may not retaliate, even 

a little; but Congress chose to exempt the employer from 

liability if the firing would have happened anyway.1

The reason why the AIR-21 standards are so well 

understood is that Congress chose to apply those same 

standards in a wide range of statutes, including Sarbanes1 The distinction between the substantive case and the affirmative 

defense can be explained using a simple analogy. Suppose that I am 

hosting a dinner party, and I plan to serve lasagna as the main dish. On 

the morning of the party, I realize that I am out of lasagna noodles and, 

although I have many after-dinner teas, I do not have one of my favorite 

teas to serve. I am pressed for time, but I decide to go to the grocery 

store. Both facts—lack of pasta and lack of a favorite tea—may have 

contributed to the decision to go shopping. But if I am asked after the 

fact, I would report that, even if I had stocked plenty of my favorite tea, 

I would have gone to the store anyway. After all, the most critical need 

for the dinner party was the main dish. The lack of tea contributed to my 

decision to go to the store, but I would have gone to the store regardless 

of my tea supply. Similarly, even when protected activity contributed to 

a firing decision, the employer escapes liability if the firing would have 

happened anyway. Nothing required Congress to provide this 

affirmative defense, of course, but we must apply the statute that 

Congress enacted. 
PARKER V. BNSF RAILWAY COMPANY 33

Oxley Act of 2002, 18 U.S.C. § 1514A(b)(2); Motor Vehicle 

and Highway Safety Improvement Act of 2012, 49 U.S.C. 

§ 30171(b)(2)(B); Surface Transportation Assistance Act, 

49 U.S.C. § 31105(b); FDA Food Safety Modernization Act, 

21 U.S.C. § 399d(b)(2)(C); Consumer Product Safety 

Improvement Act of 2008, 15 U.S.C. § 2087(b)(2)(B); 

Energy Policy Act of 1992, 42 U.S.C. § 5851(b)(3); 

American Recovery and Reinvestment Act of 2009, Pub. L. 

No. 111-5, § 1553(c)(1)(B), 123 Stat. 115, 299; Criminal 

Antitrust Anti-Retaliation Act of 2019, 15 U.S.C. § 7a3(b)(2); William M. (Mac) Thornberry National Defense 

Authorization Act for Fiscal Year 2021, Pub. L. No. 116-

283, § 6314, 134 Stat. 3388, 4601 (amending 31 U.S.C. 

§ 5323(g)(3)(A)); Taxpayer First Act, 26 U.S.C. 

§ 7623(d)(2)(B). Most pertinent here is the Federal Railway 

Safety Act (“FRSA”).

The FRSA provides that a railroad carrier may not fire or 

discipline an employee because the employee refused to 

violate a railroad safety rule. 49 U.S.C. § 20109(a). The 

FRSA expressly incorporates the AIR-21 substantive 

provisions, commanding that any enforcement action “shall 

be governed under the rules and procedures set forth in 

section 42121(b), including . . . the legal burdens of proof set 

forth in section 42121(b).” Id. § 20109(d)(2)(A). 

The district court conducted a trial in order to determine 

two questions: the initial substantive burden and the 

affirmative defense. The district court found that Curtis 

Rookaird met the initial burden of proving that air-brake 

testing—a protected activity—was one factor that 

contributed, albeit “very little,” to his dismissal. Parker v. 

BNSF Ry. Co., No. 2:14-cv-00176-RAJ, 2022 WL 897604, 

at *6–*7 (W.D. Wash. March 28, 2022). Because the 

“contributing factor” bar is so low, Rookaird established the 
34 PARKER V. BNSF RAILWAY COMPANY

elements of the claim. See Frost, 914 F.3d at 1197 (holding 

that “‘contributing factors’ may be quite modest” and may 

“play[] only a very small role” in the employer’s decision); 

Rookaird, 908 F.3d at 461 (“A ‘contributing factor’ includes 

any factor, which alone or in connection with other factors, 

tends to affect in any way the outcome of the decision.” 

(citations and some internal quotation marks omitted)). On 

appeal, neither party challenges the district court’s first 

determination.

The district court next found that BNSF Railway 

Company proved its affirmative defense by presenting clear 

and convincing evidence that it would have fired Rookaird 

anyway, even if Rookaird had not engaged in the protected 

activity of testing the brakes. Parker, 2022 WL 897604, at 

*6–*7. That second finding is the only substantive issue on 

appeal.2

The record amply supports the district court’s finding. 

On February 23, 2010, Rookaird and two other employees 

performed work, including about half an hour of conducting 

air-brake tests on railcars. Id. at *1–*2. In the judgment of 

the supervisor, the crew took far too long, and the supervisor 

told the crew to come back to the depot. Id. at *2. Once the 

crew returned, after about five-and-a-half hours of work 

during which little was accomplished, the supervisor told the 

crew to clock out and go home. Id. The other two employees 

did as they were told. Id. at *4. Rookaird, however, 

dishonestly recorded his time of departure as 8:30 p.m., 

approximately half an hour after the actual time, and he did 

not sign his timesheet. Id. at *2. Rookaird also declined to 

2 I agree with the majority opinion that the evidentiary challenges fail. I 

also follow the majority opinion’s lead in referring to the plaintiff as 

“Rookaird.”
PARKER V. BNSF RAILWAY COMPANY 35

follow the supervisor’s instruction to go home; instead, he 

started an argument with another employee, refused a second 

command to go home, and left only after receiving a third 

command to go home. Id. at *2–*3. 

After considering all the evidence, the district court first 

explained that the air-brake testing “contributed very little” 

to BNSF’s decision to fire Rookaird. Id. at *7. The air-brake 

testing accounted for only twenty to forty minutes of the 

crew’s five-and-a-half hours of inefficient work, no one told 

the crew to stop the air-brake testing, and air-brake tests 

were routine. Id. Unlike other violations, discussed below, 

inefficient work is not an independently dismissible 

violation. 

In addition to the air-brake testing’s being only a small 

part of Rookaird’s inefficiency that day, “Rookaird was fired 

for many reasons unrelated to his inefficiency.” Id. at *6 

(emphasis added). Specifically, BNSF fired Rookaird for 

lying on his timesheet and failing to sign his timesheet, 

violations of work rules that independently warranted 

dismissal, and BNSF fired Rookaird for twice disobeying 

orders to leave the premises and for causing a heated 

argument with a co-worker while he remained on site, also 

an independently dismissible violation. Id. at *6–*7. 

Indeed, both the general manager who decided to fire 

Rookaird and the Human Resources employee who 

reviewed the record and concurred in the firing decision 

testified that the dishonesty and insubordination justified 

Rookaird’s dismissal.3 In sum, the testing comprised only 

3 The Human Resources manager testified at the first trial, and the 

transcript of his testimony was admitted at the second trial. The general 

manager testified, in person, at the second trial, and the district judge 
36 PARKER V. BNSF RAILWAY COMPANY

about ten percent of the time that Rookaird and his 

crewmates worked inefficiently (which is not an 

independently dismissible offense anyway), and the testing 

had nothing at all to do with Rookaird’s dishonesty and 

insubordination (either of which is an independently 

dismissible offense).

The court additionally observed that BNSF imposed a 

much lesser sanction on the other two members of 

Rookaird’s crew. Id. at *7. Although those crew members, 

too, had worked inefficiently, they had not committed gross 

dishonesty or insubordination. The lesser punishment for 

the other crew members supports the conclusion that—

consistent with BNSF’s written policies—BNSF viewed 

Rookaird’s dishonesty and insubordination as the most 

egregious misconduct. 

The record thus strongly supports—if not compels—the 

district court’s finding that BNSF met its burden of proving 

the affirmative defense. I would affirm.

B. The Majority Opinion Significantly Errs. 

The majority opinion errs in many significant ways, 

which I group as follows: (1) the opinion ignores the “clear 

error” standard of review; (2) the opinion crafts a new, 

confusing, nonsensical, and unsupported legal standard and 

pointlessly remands for the district court to apply that bizarre 

observed that testimony firsthand. The district judge, as trier of fact and 

assessor of credibility, was entitled to believe him. See, e.g., United 

States v. Ginn, 87 F.3d 367, 369 (9th Cir. 1996) (holding that “we must 

respect the exclusive province of the trier of fact to determine the 

credibility of witnesses” (brackets and internal quotation marks 

omitted)).
PARKER V. BNSF RAILWAY COMPANY 37

standard; and (3) the opinion commits a laundry list of 

additional errors. 

1. The Opinion Ignores the “Clear Error” Standard of 

Review.

The only substantive issue on appeal is the district 

court’s finding that BNSF would have fired Rookaird 

anyway, even if he had not tested the air brakes. In a range 

of contexts, we and other circuits consistently have held that 

whether an employer would have fired an employee anyway 

is a factual determination that is reviewed for clear error. 

See Clairmont v. Sound Mental Health, 632 F.3d 1091, 1108 

(9th Cir. 2011) (holding that whether an employer “would 

have reached the same adverse employment decision even in 

the absence of the employee’s protected conduct” is “purely 

a question of fact” (brackets and internal quotation marks 

omitted)); see, e.g., Baloga v. Pittston Area Sch. Dist., 927 

F.3d 742, 752 n.7 (3d Cir. 2019) (citing an earlier precedent 

for the rule that “whether the employer would have taken 

[an] action regardless” is a “question[] for the jury”); 

Koszola v. FDIC, 393 F.3d 1294, 1300 (D.C. Cir. 2005) 

(holding that the appellate court reviews “for clear error” 

“the district court’s finding by clear and convincing evidence 

that the [employer] would have fired [the employee] 

regardless of any alleged protected activity”); Johnson v. 

Univ. of Cincinnati, 215 F.3d 561, 584 (6th Cir. 2000) 

(holding that whether the employer “would have terminated 

[the employee] in the absence of his protected conduct . . . is 

a question of fact for the jury to decide”); Bellaver v. Quanex 

Corp., 200 F.3d 485, 495 (7th Cir. 2000) (holding that 

whether the employer “would have fired [the employee] in 

the absence of discrimination” is a determination “best left 

in the hands of a jury”); Hall v. Marion Sch. Dist. No. 2, 31 

F.3d 183, 193 (4th Cir. 1994) (holding that the determination 
38 PARKER V. BNSF RAILWAY COMPANY

“whether [the employee] would have been fired ‘but for’ her 

protected speech . . . is a factual one, and therefore, is not to 

be reversed absent clear error” (internal citation omitted)); 

Daniels v. Quinn, 801 F.2d 687, 689 (4th Cir. 1986) (holding 

that “whether the employee would have been discharged ‘but 

for’ [protected] speech” is a “classic motivational question 

[that] is one of fact”).

The majority opinion states at the outset that we review 

the district court’s findings of fact for clear error, Op. at 15, 

but the opinion nowhere applies that standard to the district 

court’s finding. “We review a district court’s findings of fact 

following a bench trial for clear error, . . . and [we] will 

reverse only if the district court’s findings are . . . illogical,

implausible, or without support in inferences from the 

record.” Chaudhry v. Aragón, 68 F.4th 1161, 1171 (9th Cir. 

2023) (citations and internal quotation marks omitted). The 

majority opinion never mentions the “illogical, implausible, 

or without support” standard and never explains how the 

district court’s amply supported factual finding contravenes 

that standard. Instead, the opinion simply ignores the 

applicable standard of review. 

2. The Opinion Manufactures Legal Error by 

Announcing a Nonsensical New Legal Standard.

Apparently recognizing that no clear error exists, the 

majority opinion manufactures legal error, suggesting that 

the district court misunderstood the applicable legal 

standard. The majority opinion is plainly mistaken. The 

district court fully comprehended and faithfully applied the 

correct legal rule.

The statutory scheme is not complicated. Both as a 

matter of logic and of statutory text, the affirmative defense 

arises only if the plaintiff first proves that protected activity 
PARKER V. BNSF RAILWAY COMPANY 39

contributed, even a little, to the employer’s firing decision. 

The statute refers in earlier sub-parts to behavior that is 

protected and then queries, in the affirmative defense, 

whether the employer would have fired the employee “in the 

absence of that behavior.” 49 U.S.C. § 42121(b)(2)(B)(ii), 

(iv) (emphasis added). In other words, we reach the 

affirmative defense only after a plaintiff has proved that the 

employer impermissibly considered protected conduct. The 

finding of a contributing factor is the necessary predicate for 

the affirmative defense, not some smoking gun that 

disproves or discredits the affirmative defense (especially 

where, as here, the district court found that the protected 

conduct contributed only very little to the firing decision). 

The employer then has the burden of proving by clear 

and convincing evidence that it would have fired the 

employee anyway, if the employee had not engaged in 

protected activity. As the majority opinion correctly 

recognizes, this is a hypothetical, “counterfactual” inquiry 

that asks what the employer would have done had the 

protected activity not occurred. Op. at 25. Here is how we 

have described the rule in more formal terms: Even when 

protected activity contributes to a firing decision, the 

employer can “defeat the claim by demonstrating by clear 

and convincing evidence that the employer would have taken 

the same unfavorable personnel action in the absence of the 

protected activity.” Frost, 914 F.3d at 1195 (brackets 

omitted) (citation and internal quotation marks omitted).

That is precisely the question that the district court asked, 

and answered, here. The court could not have been clearer. 

It stated the correct legal standard three separate times. “An 

employer . . . can defeat the plaintiff’s claim if the employer 

demonstrates, by clear and convincing evidence, that the 

employer would have taken the same unfavorable personnel 
40 PARKER V. BNSF RAILWAY COMPANY

action in the absence of the protected activity.” Parker, 2022 

WL 897604, at *5 (internal quotation marks omitted). “[A]n 

employer may defeat the retaliation claim if it can 

demonstrate by clear and convincing evidence that it would 

have taken the same unfavorable action absent the protected 

activity.” Id. “An employer can defeat a claim for unlawful 

retaliation if it can prove, by clear and convincing evidence, 

that the employer would have taken the same unfavorable 

personnel action in the absence of the protected activity.” Id.

at *6 (internal quotation marks omitted). It twice 

summarized the pertinent question here in light of that legal 

standard: “whether BNSF could prove, by clear and 

convincing evidence, that it would have fired Mr. Rookaird 

absent the air test.” Id. at *1, *5. And it twice applied that 

standard in reaching its conclusion: “The Court concludes, 

by clear and convincing evidence, that absent the air test 

BNSF would have still fired Mr. Rookaird.” Id. at *6. “In 

all, the Court forms the ‘abiding conviction’ that even if Mr. 

Rookaird did not engage in the protected activity of refusing 

to stop the air test, BNSF would have still fired him for his 

gross dishonesty and insubordination. Thus, the Court 

concludes that BNSF has successfully proved its defense by 

clear and convincing evidence.” Id. at *7 (internal citation 

omitted).

The majority opinion disregards the obvious fact that the 

district court fully appreciated and applied the correct legal 

rule. Instead, the majority opinion announces a new, 

confusing, nonsensical, and unsupported legal standard. The 

majority opinion then vacates the district court’s decision 

and remands for reconsideration under the baffling new 

standard. I strongly disagree. 

The majority opinion reasons as follows. Unlike some 

statutes, the wording of the FRSA includes the provision that 
PARKER V. BNSF RAILWAY COMPANY 41

an employer may not retaliate “in whole or in part” against 

an employee. 49 U.S.C. § 20109(a). According to the 

majority opinion, the “in part” wording affects not only the 

employee’s substantive case, but also the employer’s 

affirmative defense. According to the majority opinion, “the 

FRSA affirmative defense standard needs to proceed with an 

analysis about whether and how the termination decision 

would have occurred absent the protected activity, given that 

the protected activity cannot contribute to the employer’s 

adverse action decision even in part.” Op. at 24 (emphasis 

added). We must consider the affirmative defense “with the 

understanding that the protected activity cannot contribute to 

the employer’s adverse action decision even in part.” Op. at 

28. This nebulous standard is wrong in so many ways, it is 

hard to know where to begin.4

Fundamentally, the majority opinion conflates the 

employee’s substantive burden with the employer’s 

4 The majority opinion cannot mean that, any time protected activity 

contributed a little to the firing decision, the affirmative defense is 

unavailable. That ruling would nullify the affirmative defense and 

contravene our caselaw and the law of all other circuits. E.g., Frost, 914 

F.3d at 1197; Pan Am Rys., Inc. v. U.S. Dep’t of Labor, 855 F.3d 29, 36 

(1st Cir. 2017); Metro-North Commuter R.R. Co. v. U.S. Dep’t of Labor, 

886 F.3d 97, 106 (2d Cir. 2018); Wiest v. Tyco Elecs. Corp., 812 F.3d 

319, 329 (3d Cir. 2016); Greatwide Dedicated Transp. II, LLC v. U.S. 

Dep’t of Labor, 72 F.4th 544, 553–54 (4th Cir. 2023); Yowell v. Admin. 

Review Bd., U.S. Dep’t of Labor, 993 F.3d 418, 422 (5th Cir. 2021); 

Weatherford U.S., L.P. v. U.S. Dep’t of Labor, Admin. Bd., 68 F.4th 

1030, 1040 (6th Cir. 2023); Brousil v. U.S. Dep’t of Labor, Admin. 

Review Bd., 43 F.4th 808, 812 (7th Cir. 2022); BNSF Ry. Co. v. U.S. 

Dep’t of Labor Admin. Review Bd., 867 F.3d 942, 945 (8th Cir. 2017); 

Fresquez v. BNSF Ry. Co., 52 F.4th 1280, 1296 (10th Cir. 2022). That 

ruling also would make no sense in light of the majority opinion’s 

decision to remand, because it is undisputed that the air-brake testing 

contributed to the firing decision.
42 PARKER V. BNSF RAILWAY COMPANY

affirmative defense. As we and other courts consistently 

have held, the affirmative defense asks simply what the 

employer would have done in the absence of the protected 

activity. That counterfactual inquiry assumes that the 

protected activity did not occur and asks what decision the 

employer would have made. In considering the affirmative 

defense, the legal standard that the employee must meet to 

prove the substantive case passes out of the picture and is 

simply irrelevant. The majority opinion cites a long list of 

cases that purportedly support its novel rule. But not a single 

case supports its new rule. As discussed in more detail 

below, no case gives the “in part” wording any special 

import at all. And no case comes anywhere near suggesting 

that the “in part” wording has any effect whatsoever on the 

affirmative defense. Instead, as we and other circuits have 

repeatedly held, the affirmative defense asks simply whether 

the employer would have fired the employee in the absence 

of the protected activity. See supra note 4 (listing cases). 

The reason why the “in part” wording has no meaningful 

effect is that the AIR-21 standard already encompasses the 

fact that an employee has only a minimal burden of proving 

retaliation. As we put it succinctly in Frost, “[u]nder the 

AIR-21 standard,” an employee can meet the contributingfactor standard “even if [the protected activity] played only 

a very small role in BNSF’s decision-making process.” 914 

F.3d at 1197 (emphasis added). The substantive standards 

here are no different than in any other case applying the AIR21 standards. Not a single case has held that the “in part” 

wording has any effect whatsoever on either the employee’s 

substantive case or the affirmative defense.

Finally, the majority opinion’s new standard is 

nonsensical. The affirmative defense asks simply what the 

employer would have done if the factfinder assumes that the 
PARKER V. BNSF RAILWAY COMPANY 43

protected activity never had occurred. Because the 

factfinder must assume that the protected activity does not 

exist at all, it makes no sense for the factfinder also to keep 

in mind the “understanding” that the employer cannot fire 

the employee for protected activity, even in part. Op. at 28. 

In considering the hypothetical world in which the employee 

did not engage in protected activity, the answer is either “the 

employer would have fired the employee anyway” or “the 

employer would not have fired the employee.” Whatever 

answer the factfinder reaches, the employee’s burden at the 

initial substantive step cannot possibly affect that answer. 

I do not envy the district court in this case in 

reconsidering its decision. I see no reason why the district 

court could not simply reinstate its original order, adding the 

notation that it has done so while bearing in mind that an 

employer cannot retaliate even in part. The law ordinarily 

does not suffer such irrelevant formalities. Nor do I envy 

juries in future cases, or our court in future appeals, in 

applying this nonsensical legal standard, which is premised 

on a snippet of statutory text that relates only to the 

substantive case, not to the affirmative defense.

The majority opinion’s reason for relying on that 

particular snippet of statutory text is a transparent attempt to 

limit the damage that its opinion does to our caselaw. The 

opinion specifically limits its holding to FRSA cases. Op. at 

23. But its rule clearly applies more broadly, to all cases 

involving the AIR-21 standards, because those standards 

already encompass the minimal level of retaliation that an 

employee must show. 
44 PARKER V. BNSF RAILWAY COMPANY

3. The Majority Opinion Commits a Laundry List of 

Additional Errors. 

The majority opinion’s flailing analysis also commits a 

laundry list of additional errors. I address a few of them 

here.

a. The majority opinion mentions, no fewer than six 

times, BNSF’s purported concession as to the contributingfactor determination. Op. at 4–5, 13 (twice), 21, 27. The 

opinion describes that purported concession as 

“particularly” important and a “finding of particular note,” 

and the opinion implies that the concession makes it harder 

for BNSF to prove the affirmative defense. Id. at 5, 13. 

Those statements are wholly illogical and unprecedented. 

The affirmative defense kicks in only if the plaintiff 

establishes an improper contributing factor. The majority 

opinion cites no legal support, and none exists, for the 

proposition that it matters how the plaintiff establishes that 

fact—whether by “concession,” by a ruling at summary 

judgment, by stipulation, by a finding by the trier-of-fact, or 

otherwise.5

5 The purported “concession” at issue here is not a formal concession by 

a party. To the contrary, the court conducted a trial to rule on this 

disputed issue of fact. Parker, 2022 WL 897604, at *1. In its post-trial 

decision, the district court cited testimony by BNSF employees that they 

considered the air-brake testing, and the court wrote that BNSF 

“concedes” the issue. Id. at *6. Read in context, the court meant only 

that BNSF’s own employees testified that they considered the testing; 

the court clearly did not intend to give its statement any greater weight 

than that. Regardless, as explained in text, whether BNSF formally 

conceded the issue or simply lost at trial on the issue is irrelevant to 

assessing the affirmative defense. The key point is that the contributingfactor finding is merely a necessary predicate for the affirmative defense, 

not some critical fact that by itself discredits the defense.
PARKER V. BNSF RAILWAY COMPANY 45

b. As another example, BNSF concluded that Rookaird 

was dishonest in recording his sign-out time as 8:30 p.m., 

because he actually signed out at 8:02 p.m. The opinion 

implies that Rookaird was not in fact dishonest because the 

sign-out time was “within the thirty-minute grace period 

permitted by BNSF’s policies and practices.” Op. at 8. The 

district court found to the contrary, Parker, 2022 WL 

897604, at *6–*7, and the majority opinion never explains 

why that finding was clearly erroneous. Moreover, the 

majority opinion misunderstands the “grace period.” 

Nothing in the record suggests that an employee could add 

30 minutes to their workday for no reason at all. The policy 

appears to have set a goal for employees to log out for the 

day within 30 minutes of completing actual work on the 

railcars, presumably because, as was true with the work that 

Rookaird’s crew performed on the day in question, the actual 

labor sometimes was not near the computer system. A 

similar policy applied to arrival times: an employee was 

expected to be doing actual work on the railcars, or 

elsewhere, within 30 minutes of signing in. But nothing in 

the record, nor in common sense, suggests that employees 

could add up to 60 minutes of work time just because a 

computer system allowed it.

To the contrary, every BNSF employee who testified on 

the subject testified that Rookaird had no justification for 

adding 28 minutes to his sign-out time and that, accordingly, 

he violated company policy. Rookaird himself testified that 

he had no justification for adding the time, other than the fact 

that the computer system allowed it. The other two members 

of Rookaird’s crew, who received the same command to sign 

out, accurately logged their sign-out times. Evidence in the 

record shows that BNSF had disciplined other employees for 

adding time to their workdays without justification. The 
46 PARKER V. BNSF RAILWAY COMPANY

majority opinion’s statement that Rookaird’s adding of 28 

minutes to his workday was “within the 30-minute grace 

period permitted by BNSF’s policies and practices,” Op. at 

8, is wholly unsupported by the record. There is no question 

that Rookaird was dishonest in completing his timesheet. 

c. The majority opinion implies that the district court 

misunderstood the legal standard by deciding only whether 

BNSF “could have” fired Rookaird. Op. at 5, 25. The 

majority opinion implies that the court did not determine 

whether BNSF “would have” fired Rookaird. Id. I am 

baffled by the suggestion. As described in detail above, the 

district court stated the legal standard eight times and, in all 

eight instances, the court used the correct “would have” 

formulation. Parker, 2022 WL 897604, at *1, *5 (thrice), *6 

(twice), *7 (twice). Nothing suggests that the court 

misunderstood the legal standard. 

d. The majority opinion’s discussion of an employer’s 

efforts to dissuade an employee from engaging in protected 

activity is wrong on both the facts and the law. The majority 

opinion states—as fact—that BNSF attempted to dissuade 

Rookaird from engaging in protected activity. Op. at 27–29. 

But the district court made no such factual finding, and the 

majority opinion relies on its own inferences from 

ambiguous testimony to reach that conclusion. The majority 

opinion plainly steps outside its role as reviewing court and 

impermissibly acts as finder of fact.

The majority opinion compounds the factual error by 

committing legal error. The opinion quotes BNSF Railway 

Co. v. United States Department of Labor, 816 F.3d 628, 641 

(10th Cir. 2016), for the proposition that an employee 

“can . . . show an ‘overwhelming’ case of FRSA retaliation 

by presenting evidence that the employer tried to dissuade 
PARKER V. BNSF RAILWAY COMPANY 47

him from engaging in the protected activity.” Op. at 27. But 

BNSF Railway used the word “overwhelming” only in a 

parenthetical; to a “cf.” citation; describing another case as 

having “less than overwhelming” facts. BNSF Railway, 816 

F.3d at 641 (emphasis added). Retaliation cases are 

inherently fact-specific, and no one factor necessarily 

controls. Contrary to the majority opinion’s implication, 

there is no rule that any time an employer attempts to 

dissuade an employee, the employee necessarily has an 

“overwhelming” case. And this entire topic is irrelevant here 

because the district court did not find that BNSF engaged in 

dissuasion. 

e. The majority opinion next appears to fault the district 

court for reasoning, in part, that the air-brake testing 

contributed very little to BNSF’s firing decision. As 

described above, the district court found that BNSF 

established the affirmative defense for a combination of 

reasons: (1) the protected activity contributed very little to 

the firing decision; (2) wholly apart from the protected 

activity, Rookaird engaged in egregious conduct constituting 

several independently dismissible violations; and (3) BNSF 

imposed lesser sanctions on employees who did not engage 

in that same unprotected conduct. The majority opinion 

focuses on the first reason only and states: “The proper 

inquiry, however, is not whether the protected activity 

‘contributed very little’ to the firing; the proper inquiry is 

whether BNSF would have fired Rookaird regardless of 

whether he had conducted an air-brake test.” Op. at 24. The 

district court plainly asked the proper question whether 

BNSF would have fired Rookaird anyway; it did not inquire 

solely into whether the protected activity contributed very 

little. To the extent that the majority opinion reads the 
48 PARKER V. BNSF RAILWAY COMPANY

district court’s opinion as relying solely on that one factor, 

the majority opinion is clearly wrong. 

Nor was there anything improper about the district 

court’s considering whether the protected activity played a 

large or a small role in the decision to fire the employee. As 

a matter of common sense, the role that the protected activity 

played in the firing decision bears directly on the credibility 

of an employer’s explanation that it would have fired the 

employee in the absence of the protected activity. For 

example, if the protected activity was the centerpiece of a 

firing decision, an employer will have a much harder time 

convincing a finder of fact that it would have fired the 

employee anyway. Or, as here, if the protected activity 

played only a small role and the nonprotected conduct was 

egregious, then the employer’s “we would have fired him 

anyway” explanation has more credibility. 

Nothing in the law suggests that a factfinder must 

disregard the logically salient factor of the role that the 

protected activity played in the firing decision. The majority 

opinion cites no support for that unprecedented, irrational 

rule, and the rule runs counter to the same decisions that the 

majority opinion cites favorably. See, e.g., Brousil, 43 F.4th 

at 812 (“[T]he [Administrative Review Board] has 

admonished factfinders to ‘holistically consider any and all 

relevant, admissible evidence’ . . . [and] no circuit court or 

later ARB decision has limited the factfinder’s ability to look 

at all relevant evidence.”).

f. The majority opinion misunderstands the employee’s 

initial substantive burden of proving that protected activity 

must have contributed to the firing decision. The opinion 

states, without citation or other support: “An FRSA 

employer may still be able to prove an affirmative defense 
PARKER V. BNSF RAILWAY COMPANY 49

where a plaintiff shows only a correlation between the 

protected activity and adverse action, but this is less likely 

where a factfinder determines that the protected activity 

caused an employer’s adverse action, even in part.” Op. at 

23–24. An employee must show that protected activity 

actually contributed to the firing decision; merely showing 

that some activity correlated with the firing decision will not 

suffice. Rookaird, 908 F.3d at 462–63. The majority 

opinion’s mischaracterization of the initial substantive 

burden fails to respect the law of the case and will cause yet 

more confusion in this—until now—settled area of law.

I dissent.