                                                                                FILED
                                                                    United States Court of Appeals
                                      PUBLISH                               Tenth Circuit

                     UNITED STATES COURT OF APPEALS                         June 2, 2015
                                                                       Elisabeth A. Shumaker
                                  TENTH CIRCUIT                            Clerk of Court


 MELVIN L. MATHIS,

       Plaintiff - Appellant,

 v.                                                         No. 13-8082

 HUFF & PUFF TRUCKING, INC., a
 Tennessee corporation; DONALD
 STEWART,

       Defendants - Appellees.



           APPEAL FROM THE UNITED STATES DISTRICT COURT
                   FOR THE DISTRICT OF WYOMING
                     (D.C. No. 2:12-CV-00029-NDF)


Frederick J. Harrison, Rawlins, Wyoming, appearing for Appellant.

Patrick J. Murphy (David E. Shields with him on the brief), Williams, Porter, Day &
Neville, P.C., Casper, Wyoming, appearing for Appellees.


Before BRISCOE, Chief Judge, MURPHY and MATHESON, Circuit Judges.


MATHESON, Circuit Judge.


      On February 18, 2008, Donald Stewart, driving a semi-tractor trailer, hit the back

of a tow truck driven by Melvin Mathis. Mr. Mathis sued Mr. Stewart and his employer,
Huff & Puff Trucking, Inc., for negligence in the District of Wyoming. On August 9,

2013, after a bench trial, the district court issued findings of fact and conclusions of law.

The court determined Mr. Stewart was 100 percent at fault for the accident, and entered

judgment in favor of Mr. Mathis. The damages award, which was significantly less than

Mr. Mathis sought, was based on findings that his spinal injuries from the accident were

only temporary and he did not suffer a mild traumatic brain injury (“MTBI”). On

September 6, 2013, Mr. Mathis moved for a new trial, arguing, among other things, that

the judge’s law clerk had an undisclosed conflict of interest. The court denied the

motion.

       On appeal, Mr. Mathis challenges (1) the district court’s factual findings relating

to his back and head injuries, (2) whether the court impermissibly allowed a defense

expert to testify beyond his qualifications as a biomechanical engineer, and (3) the court’s

denial of his motion for a new trial based on the alleged law clerk conflict. 1 Exercising

jurisdiction under 28 U.S.C. § 1291, we affirm.

                                   I. BACKGROUND

                                   A. Factual History

       On February 18, 2008, Mr. Stewart, a driver for Huff & Puff, hit Mr. Mathis’s tow

truck from behind with his semi-tractor trailer on Interstate 80 near Rawlins, Wyoming.

       1
         Mr. Mathis also challenges the district court’s damages award as clearly
erroneous. He does not, however, raise any independent ground for reversing the court’s
damages award beyond his challenge to the district court’s factual findings. Our
determination that the district court’s factual findings were not clearly erroneous resolves
this issue.

                                             -2-
Mr. Stewart was at fault for the accident. He was driving too fast for the icy road

conditions and should not have been traveling in the left lane. The crash damaged the

tow truck, but Mr. Mathis was “ambulatory, functional and coherent” immediately

following the accident. App. at 74. He called 911, and an ambulance took him to the

emergency room. The emergency room doctor found no evidence of head trauma, but

noted Mr. Mathis strained his neck and back. Mr. Mathis was released later that evening.

       Before the accident, Mr. Mathis had a back condition. He had undergone spinal

surgeries in 1989 and 1993. Four days after the accident, Mr. Mathis saw Dr. Kenneth

Schulze for follow-up care for his back and neck pain. Dr. Schulze reviewed x-rays

taken the day of the accident and ordered MRIs of Mr. Mathis’s spine. He concluded

Mr. Mathis suffered “multiple areas of sprain” to his spine from the collision. Aplee.

Supp. App. at 78. He noted Mr. Mathis had preexisting disc lesions, which the accident

had aggravated. He referred Mr. Mathis to Dr. Judson Cook, a neurosurgeon at

Wyoming Spine and Neurosurgery Associates, L.L.C.

       Dr. Cook diagnosed Mr. Mathis with “cervical, thoracic and lumbar sprains

and/or material aggravation of preexisting asymptomatic degenerative [spinal] disease.”

App. at 81. He prescribed a conservative treatment plan of physical therapy and

massage. He allowed Mr. Mathis to return to light duty work in March 2008 and

removed all work restrictions except avoiding heavy or repeated lifting in April 2008.

Mr. Mathis saw Dr. Cook several times over the next year. Dr. Cook reported that Mr.




                                            -3-
Mathis’s condition was slowly improving, though he was still symptomatic and

experiencing discomfort.

       In May 2009, Mr. Mathis saw Dr. Cook for the last time. Dr. Cook reported that

Mr. Mathis “was doing fairly well with conservative and medical management.” Id. at

83. Mr. Mathis requested to continue conservative therapy and planned to see Dr. Cook

in two months for a follow-up appointment. Following the May 2009 visit, however, Mr.

Mathis did not return to Wyoming Spine and Neurosurgery for nearly two years.

       During those two years, Mr. Mathis worked as a nighttime fuel delivery man,

working 12-hour shifts, 20 to 25 days a month. Mr. Mathis was under no work

restrictions, and the job was physically demanding, requiring him to drag a 200-foot hose,

refuel multiple pieces of fracking equipment, and install heavy tire chains to get around.

In 2011, his employer lost a big fuel delivery contract. After that, Mr. Mathis continued

to work full time doing mechanic work, driving a tow truck, and delivering fuel as

needed.

       In April 2011, Mr. Mathis returned to Wyoming Spine and Neurosurgery and saw

a different neurosurgeon, Dr. Steven Beer. Mr. Mathis complained about lower back

pain, and Dr. Beer ordered new MRIs and x-rays. The images were essentially

unchanged from the MRIs and x-rays taken in 2008. In September 2012, Dr. Beer

performed two-level lumbar fusion surgery on Mr. Mathis to relieve his chronic pain.




                                            -4-
                                B. Procedural History

1. Initiation of Lawsuit and Bench Trial

       On February 9, 2012, Mr. Mathis filed this negligence action in the District of

Wyoming against Mr. Stewart and Huff & Puff (“Defendants”). From July 8 to July 19,

2013, the district court conducted an 8-day bench trial. At trial, Mr. Mathis argued the

accident caused permanent injuries to his spine, an MTBI, emotional distress, and pain

and suffering. He further contended his injuries required ongoing medical care and

reduced his future earning capacity. The district court heard competing evidence

regarding Mr. Mathis’s spinal and head injuries. 2

2. Testimony about Mr. Mathis’s Spinal Injury

       On Mr. Mathis’s back injuries, Dr. Beer testified for Mr. Mathis. Dr. Mark

Hadley, a neurosurgeon, and Dr. Toby Hayes, a biomechanical engineer, testified for the

Defendants.

       Dr. Beer testified that “the degenerative changes present in Mathis’ cervical and

lumbar spine became symptomatic because of the February 2008 collision.” App. at 86.

Dr. Beer applied a “differential diagnosis approach,” concluding the accident caused the

injuries because Mr. Mathis’s “spondylosis was asymptomatic before the accident, and

symptomatic after.” Id. As the court observed, “[a]ccording to Dr. Beer, this finding is

consistent with an acute or subacute process, consisting of trauma causing or contributing

       2
        The court also heard competing evidence regarding causation of the accident.
The court concluded Mr. Stewart was 100 percent at fault. This finding is not disputed
on appeal.

                                            -5-
to a material aggravation of Mathis’ preexisting asymptomatic degenerative disease

present in the cervical and lumbar areas of the spine.” Id. Dr. Beer said bulging discs

and a small annular tear in Mr. Mathis’s L4/L5 disc supported his findings. He further

described Mr. Mathis’s “two-year gap in treatment as consistent with a patient who is

attempting to avoid surgery for as long as possible.” Id. at 86-87.

       Dr. Hadley testified Mr. Mathis’s “medical records show no evidence of injury

from the collision other than temporary muscular-skeletal injuries.” Id. at 87. He

explained the images of Mr. Mathis’s spine “show a typical degenerative lumbar spine,”

caused by aging. Id. He acknowledged there were disc bulges, but said they were all old.

He disagreed with Dr. Beer’s determination that Mr. Mathis suffered a very small annular

tear. Dr. Hadley testified that because the white dot Dr. Beer identified as an annular tear

appeared on both the 2008 and 2011 images, it is related to age “because such tears don’t

remain acute for three years.” Id. He concluded the 2011 surgery “addressed only age-

related narrowing,” and no further operation would help relieve Mr. Mathis’s pain. Id.

He further identified age, arthritis, deconditioning, and smoking as potential factors

contributing to Mr. Mathis’s pain.

       Dr. Hayes testified regarding biomechanical injury causation. He evaluated the

forces of the collision and whether those forces were likely to cause the types of injuries

Mr. Mathis claimed he suffered. Dr. Hayes concluded “the forces involved in the

accident are far below the ‘more-likely-than-not’ known injury tolerance thresholds for

risk of injury to Mathis’ low back, cervical spine and brain.” Id. at 88. Specifically, he

                                             -6-
explained the potential for low back injury—like the type of injury Mr. Mathis claims he

suffered from the accident—is “particularly low in rear-end automobile collisions when

the low back stays in contact with the seatback.” Aplee. Supp. App. at 168-69.

3. Testimony about Mr. Mathis’s Alleged Mild Traumatic Brain Injury

       In February 2013, Mr. Mathis saw a life-care planner, Francine Mazone, who

suggested he might have an MTBI. 3 At her suggestion, Mr. Mathis saw a

neuropsychologist, Dr. Dennis Helffenstein. Thereafter, the Defendants also hired a

neuropsychologist, Dr. Paul Richards, to test Mr. Mathis for MTBI.

       Dr. Helffenstein testified Mr. Mathis suffered an MTBI from the 2008 accident.

He further explained as follows. Mr. Mathis meets the diagnostic criteria for MTBI

because “there is a notable gap in [Mr. Mathis’s] memory” immediately after the

accident. Aplee. Supp. App. at 143-44. Mr. Mathis had no memory of pulling himself

upright or pulling his vehicle to the side of the road after the impact. This suggested “a

brief period of post-traumatic amnesia for some events immediately following the

accident.” Id. at 144. The application of the diagnostic criteria is “the beginning point of

the [MTBI] diagnosis process; it is not the endpoint.” Trial Tr., Vol. IV at 780. Mr.


       3
         According to the widely-accepted MTBI diagnostic standard, a patient who has
suffered an MTBI must exhibit one of the following four criteria: (1) “any period of loss
of consciousness,” (2) “any loss of memory for events immediately before or after the
accident,” (3) “any alteration in mental state at the time of the accident (eg, feeling dazed,
disoriented, or confused),” or (4) “focal neurological deficit(s) that may or may not be
transient.” Aplee. Supp. App. at 141 (Thomas Kay et al., Definition of Mild Traumatic
Brain Injury, 8 J. Head Trauma Rehabilitation 86, 86 (1993)).


                                             -7-
Mathis’s neurological test scores showed memory impairment, his auditory and visual

concentration scores ranged from impaired to average, and his verbal reasoning and

judgment results were below average—all of which are “pretty classic findings” for

patients with an MTBI. Id. at 831.

       To support his MTBI claim, Mr. Mathis also offered the testimony of his wife,

Nada Mathis; his stepdaughter, Hope Waldner; and his former boss, Gregg Waldner.

Mrs. Mathis testified that since the accident her husband had been short-tempered,

frustrated, and depressed, and that, about a year and a half before trial, Mr. Mathis began

stuttering. 4 Ms. Waldner and Mr. Waldner both testified Mr. Mathis’s personality

changed after the accident, and that he had trouble focusing at work.

       Defendants’ expert, Dr. Richards, testified Mr. Mathis did not suffer an MTBI

from the collision. He cited the lack of documentation indicating confusion or memory

loss immediately after the accident. He disagreed with Dr. Helffenstein’s “notable gap”

testimony, reporting that in his interview with Mr. Mathis, he did not find any gap in Mr.

Mathis’s memory immediately after the accident, but rather that Mr. Mathis “had a quite

good recollection of the time immediately post-injury.” Trial Tr., Vol. VI at 1498.

Finally, Dr. Richards testified that “[i]n comparison to his same-aged male peers with

comparable education . . . Mr. Mathis generally demonstrated an intact ([a]verage and

above) neuropsychological profile with only one documented deficit,” relating to his


       4
          Evidence presented at trial indicated Mr. Mathis stuttered as a child, and the
stutter re-emerged several months after the accident.

                                             -8-
processing speed. Aplee. Supp. App. at 131. Dr. Richards explained that many non-

neurological factors could deflate Mr. Mathis’s processing speed score, including

depression, chronic pain, or lack of sleep. And “[a]ny recent problems [Mr. Mathis] is

reportedly experiencing, with stuttering, work finding, or cognitive functioning are

naturally occurring problems, and not caused or aggravated by any injury from [the

accident].” Aplee. Supp. App. at 133.

       Dr. Hayes also testified that the force of the collision was “well below the levels

necessary to produce concussion or mild traumatic brain injury.” Aplee. Supp. App. at

169.

4. District Court’s Findings of Fact and Conclusions of Law

       On August 9, 2013, the district court issued findings of fact and conclusions of

law. The court rejected Mr. Mathis’s claim he suffered permanent spinal injuries.

Instead, it concluded “[t]he weight of the evidence supports finding that [Mr.] Mathis

suffered various temporary muscular-skeletal sprains from the collision, which resolved

in approximately mid-2009 following conservative therapy.” App. at 89. The court

listed eight reasons explaining its finding, and it rejected Dr. Beer’s differential diagnosis

conclusion. It explained, “While Dr. Beer’s differential diagnosis testimony might be

persuasive if that were the only testimony in the case, such testimony is overwhelmed by

the other evidence listed above.” Id. at 90.

       The district court also found Mr. Mathis did “not suffer MTBI from the 2008

collision.” Id. at 92. It based this finding on its “view that the testimony from Dr.

                                               -9-
Richards and Dr. Hayes is more persuasive than the testimony from Dr. Helffenstein.”

Id. It said Dr. Helffenstein placed “undue emphasis” on Mr. Mathis’s claimed memory

loss, which was both inconsistent with Mr. Mathis’s other statements in the record and

inconsequential given the details from the accident Mr. Mathis “admittedly remembers.”

Id. at 92. The court further explained that “no medical documentation indicates that

[Mr.] Mathis was confused, disoriented, or repeated information or questions indicative

of MTBI.” Id. It stated, “[I]t strains credulity to attribute [Mr.] Mathis’ below-average

testing scores to [an] MTBI from a collision that occurred five years earlier.” Id. at 93.

       Based on its findings, the district court awarded Mr. Mathis $145,582 in damages:

$30,000 for reasonable medical and out-of-pocket expenses incurred through mid-2009;

$100,000 for past emotional distress, pain and suffering, and loss of enjoyment of life;

and $15,582 for loss of income from 2008 to mid-2009.

5. Alleged Undisclosed Law Clerk Conflict

       Two weeks after trial, Mr. Mathis’s attorney, Frederick Harrison, learned of a

potential issue regarding the district judge’s law clerk and her husband, a partner at a

Wyoming law firm. 5 On July 15, 2013, Huff & Puff’s insurer, American International




       5
         Mr. Harrison stated in his affidavit before the district court that he learned of the
potential conflict “over a week after the trial.” App. at 108. He subsequently clarified, in
a 28(j) letter to this court, that he learned of the potential conflict on August 2, 2013, two
weeks after trial had concluded.

                                             -10-
Group, Inc. (“AIG”), hired the husband’s firm to monitor the second week of trial. 6 It did

so after learning that, over the prior weekend, Mr. Harrison had met with Huff & Puff’s

personal attorney to discuss the possibility of entering into a consent judgment with Huff

& Puff in excess of its policy limit with AIG and pursuing a bad faith action against

AIG. 7 This did not happen, but AIG hired the husband’s firm to monitor the remainder

of trial, paying on an hourly basis. Three partners, including the law clerk’s husband,

shared monitoring responsibility. Although Mr. Harrison was aware the husband was

monitoring the trial, he did not know the clerk and her husband were married until

another attorney brought it to his attention after trial had ended.

       The law clerk was present for all pretrial proceedings and was in the courtroom

throughout trial. The day her husband first appeared in the gallery, she advised the judge

she had learned the previous evening her husband had been asked to monitor the trial for

AIG. The clerk inquired if she should separate herself from the case. The judge

responded that she—the judge—would be drafting and finalizing the opinion in the case

herself, and that AIG “was not a party in the proceeding and it had no visible presence at

trial,” nor had the clerk’s husband entered an appearance in the case. Id. at 153. The

       6
        AIG had previously hired Patrick J. Murphy and his firm, Williams, Porter, Day
& Neville, to represent its insureds, Huff & Puff and Mr. Stewart, in Mr. Mathis’s
negligence suit.
       7
         Huff & Puff would enter into a judgment for an amount in excess of Huff &
Puff’s $1 million policy limit with AIG and assign its rights against AIG to Mr. Mathis.
Mr. Mathis would covenant not to collect the judgment against Huff & Puff, but instead
would seek to collect the entire judgment against AIG if he could later prove AIG acted
in bad faith.

                                             -11-
judge told the clerk she had no duty to separate herself from the case, but allowed the

clerk to attend trial only in a ministerial and observational role.

       The judge wrote in the memorandum order denying Mr. Mathis’s motion for a

new trial that once trial concluded and the case was taken under advisement, the law clerk

had no further contact with the case, and that she—the judge—researched, drafted, and

finalized the opinion based on the record and her personal notes.

6. Mr. Mathis’s Motion for a New Trial

       On September 6, 2013, seven weeks after trial had ended and five weeks after he

had learned about the law clerk and her husband’s relationship, Mr. Mathis filed a motion

for a new trial under Federal Rule of Civil Procedure 59(a) and a motion to alter or

amend the judgment under Rule 59(e). In his motion for a new trial, Mr. Mathis argued:

(1) the evidence did not support the district court’s factual findings that Mr. Mathis

suffered only a temporary sprain and did not suffer an MTBI; (2) the court erroneously

relied on Dr. Hayes’s testimony because it went beyond his qualifications as a

biomechanical engineer; and (3) the law clerk had an undisclosed conflict of interest.

The motion to alter or amend the judgment argued the judgment should be amended to

correct an inadequate damages award based on the court’s erroneous rulings. The court

denied both motions.

       Mr. Mathis timely appealed.




                                             -12-
                                     II. DISCUSSION

       On appeal, Mr. Mathis argues the district court erred in (A) finding he suffered

only a temporary sprain and did not suffer an MTBI, (B) admitting Dr. Hayes’s testimony

as going beyond his qualifications as a biomechanical engineer, and (C) denying his

motion for a new trial based on the alleged undisclosed law clerk conflict. We conclude

the record supports the district court’s factual findings regarding Mr. Mathis’s injuries,

Mr. Mathis did not adequately challenge Dr. Hayes’s testimony in the district court, and

the alleged law clerk conflict does not warrant a new trial. Accordingly, we affirm the

district court’s judgment.

                          A. District Court’s Factual Findings

1. Standard of Review

       Mr. Mathis challenges two of the district court’s factual findings. “In an appeal

from a bench trial, such as in this case, we review the district court’s factual findings for

clear error . . . .” Holdeman v. Devine, 572 F.3d 1190, 1192 (10th Cir. 2009) (quotations

omitted). “A finding of fact is clearly erroneous if it is without factual support in the

record or if, after reviewing all the evidence, we are left with a definite and firm

conviction that a mistake has been made.” Sw. Stainless, LP v. Sappington, 582 F.3d

1176, 1183 (10th Cir. 2009) (quotations omitted). “In conducting this review, we view

the evidence in the light most favorable to the district court’s ruling and must uphold any

district court finding that is permissible in light of the evidence.” Id. (quotations

omitted).


                                             -13-
       “It is not the role of an appellate court to retry the facts, because the court below

has the exclusive function of appraising credibility, determining the weight to be given

testimony, drawing inferences from facts established, and resolving conflicts in the

evidence.” Holdeman, 572 F.3d at 1192 (quotations omitted). “That the record supports

a view of the evidence that is permissible but contrary to the trial court’s findings is not

sufficient to warrant upsetting the lower court’s findings.” Id. “Where there are two

permissible views of the evidence, the factfinder’s choice between them cannot be clearly

erroneous.” Anderson v. City of Bessemer City, N.C., 470 U.S. 564, 573 (1985).

2. Analysis

       a. Spinal injury

       First, Mr. Mathis challenges the district court’s finding his spinal injuries from the

accident were only temporary sprains. He argues the court unduly relied on medical

records and that it gave inadequate weight to the testimony of Dr. Beer, Mrs. Mathis, Ms.

Waldner, and Mr. Mathis’s former employer, Mr. Waldner. We conclude Mr. Mathis has

not shown that the court’s spinal injury finding is clearly erroneous.

       Trial evidence supported the district court’s finding. The court’s order included

16 findings addressing Mr. Mathis’s spinal injuries from the accident. The court

considered extensive evidence presented in Mr. Mathis’s medical records since the

accident, including records from Dr. Schulze, Dr. Cook, and Dr. Beer. It also considered

the testimony of Mr. Mathis, Mrs. Mathis, Mr. Waldner, Dr. Beer, Dr. Hadley, Dr. Hayes,

and others. The court determined Mr. Mathis suffered only temporary muscular-skeletal

                                             -14-
sprains from the collision, and the sprains resolved in approximately mid-2009. Among

other evidence, the court based this finding on post-collision medical records diagnosing

Mr. Mathis with “cervical, thoracic, and lumbar sprains”; Mr. Mathis’s two-year gap in

treatment when he was engaged in strenuous employment activities; and medical records

after the two-year gap in treatment attributing his spinal issues to a degenerative

condition and not the accident. App. at 89. The court also based the finding on the

testimony of defense experts Dr. Hadley and Dr. Hayes. It determined “Dr. Beer’s

differential diagnosis testimony . . . [was] overwhelmed by the other evidence [in the

case].” App. at 90.

       Mr. Mathis’s reference to testimony contrary to the court’s finding does not

establish clear error: “[P]ointing to conflicting evidence inconsistent with the district

court’s finding is insufficient, standing alone, to establish clear error.” Penncro Assocs.,

Inc. v. Sprint Spectrum, L.P., 499 F.3d 1151, 1161 (10th Cir. 2007). “[E]very trial is

replete with conflicting evidence, and in a bench trial, it is the district court, which enjoys

the benefit of live testimony and has the opportunity firsthand to weigh credibility and

evidence, that has the task of sorting through and making sense of the parties’ competing

narratives.” Watson v. United States, 485 F.3d 1100, 1108 (10th Cir. 2007). The district

court resolved the parties’ conflicting evidence in favor of the Defendants. The court’s

finding that Mr. Mathis’s spinal injuries were only temporary was not clearly erroneous.




                                             -15-
       b. Mild traumatic brain injury

       Second, Mr. Mathis challenges the district court’s finding he did not suffer an

MTBI. He attacks the finding as “simplistic,” Aplt. Br. at 41, and contends the court

“completely ignored” many facts and nuances showing that he suffered an MTBI, id.

Specifically, he argues the court’s finding does not adequately address the testimony of

Dr. Helffenstein, Mrs. Mathis, Ms. Waldner, and Mr. Waldner.

       Again, the record supports the court’s finding. Mr. Mathis’s primary argument is

the district court gave Dr. Helffenstein’s testimony short shrift. A district court’s factual

findings need not contain every detail of a witness’s trial testimony. Lesch v. United

States, 612 F.3d 975, 981 (8th Cir. 2010) (“[F]indings of fact should be clear, specific,

and complete, without unrealistic and uninformative generality on the one hand, and

without an unnecessary and unhelpful recital of nonessential details of evidence on the

other.” (quotations omitted)). The court adequately explained why it found Dr.

Helffenstein’s testimony unpersuasive, noting he “placed undue emphasis on [Mr.]

Mathis’ statement that he does not remember moving his vehicle to the side of the road,”

App. at 92, and that this memory loss testimony was inconsistent with Mr. Mathis’s other

testimony. That the court found Dr. Richards’s testimony more persuasive than Dr.

Helffenstein’s does not make its finding clearly erroneous.

       Mr. Mathis again attempts to establish clear error by pointing to conflicting

testimony. The evidence, however, supports the district court’s finding that Mr. Mathis

did not suffer an MTBI. The court relied on Dr. Richards’s testimony that Mr. Mathis

                                             -16-
did not meet any of the diagnostic criteria for MTBI, did not have memory loss about the

accident, and his below-average test scores were likely related to non-neurological

factors. The court further relied on the lack of medical records from the five years after

the accident demonstrating any suspicion, much less a diagnosis, that Mr. Mathis suffered

from an MTBI. Because the evidence presented at trial supported the court’s factual

finding, we conclude the finding was not clearly erroneous.

                       B. Admission of Dr. Hayes’s Testimony

1. Legal Background and Standard of Review

       Under Federal Rule of Evidence 702,

       [a] witness who is qualified as an expert by knowledge, skill, experience,
       training, or education may testify in the form of an opinion or otherwise if:
       (a) the expert’s scientific, technical, or other specialized knowledge will
       help the trier of fact to understand the evidence or to determine a fact in
       issue;
       (b) the testimony is based on sufficient facts or data;
       (c) the testimony is the product of reliable principles and methods; and
       (d) the expert has reliably applied the principles and methods to the facts of
       the case.

Fed. R. Evid. 702. “[Rule] 702 imposes upon the trial judge an important ‘gate-keeping’

function with regard to the admissibility of expert opinions.” Ralston v. Smith & Nephew

Richards, Inc., 275 F.3d 965, 969 (10th Cir. 2001); see also Daubert v. Merrell Dow

Pharms., Inc., 509 U.S. 579, 592-93 (1993). To determine whether an expert’s opinion is

admissible, the district court must undertake a two-step analysis. United States v.

Nacchio, 555 F.3d 1234, 1241 (10th Cir. 2009) (en banc). First, the court must determine

whether the expert is “qualified ‘by knowledge, skill, experience, training, or education’


                                            -17-
to render an opinion.” Id. (quoting Fed. R. Evid. 702). Second, “the court must

determine whether the expert’s opinion is reliable by assessing the underlying reasoning

and methodology, as set forth in Daubert.” Id.

       When an appellant properly preserves an objection to expert evidence, we review

whether the district court applied the proper legal test in admitting expert testimony de

novo and the court’s application of that standard for abuse of discretion. Nacchio, 555

F.3d at 1241. But when, as here, “there is no objection to the expert testimony, the

opposing party waives appellate review absent plain error.” Goebel v. Denver & Rio

Grande W. R.R. Co., 215 F.3d 1083, 1088 n.2 (10th Cir. 2000). “To show plain error, a

party must establish the presence of (1) error, (2) that is plain, which (3) affects

substantial rights, and which (4) seriously affects the fairness, integrity, or public

reputation of judicial proceedings.” Richison v. Ernest Grp., Inc., 634 F.3d 1123, 1128

(10th Cir. 2011).

2. Analysis

       Mr. Mathis challenges only whether Dr. Hayes’s testimony exceeded the scope of

his qualifications as a biomechanical engineer. Relying on Smelser v. Norfolk Southern

Railway Co., 105 F.3d 299 (6th Cir. 1997), he argues the district court improperly

allowed Dr. Hayes to testify that the forces involved in the collision were insufficient to

cause Mr. Mathis’s injuries. Biomechanical engineers, he contends, are qualified to

testify only to “what injury causation forces are in general and . . . how a hypothetical




                                             -18-
person’s body will respond to them,” not how a specific person will respond to an

accident. Aplt. Br. at 43 (quoting Smelser, 105 F.3d at 305) (emphasis omitted).

       The district court received expert testimony through pre-filed witness statements,

which were admitted into evidence before trial. At trial, the experts took the witness

stand for cross-examination and redirect examination. Defendants argue Mr. Mathis

forfeited any objection to the scope of Dr. Hayes’s testimony because, as the district court

explained in its denial of Mr. Mathis’s motion for a new trial, Mr. Mathis never filed an

objection to Dr. Hayes’s witness statement nor did he object to any questions seeking to

elicit such testimony during trial. We agree.

       Mr. Mathis did not file a Daubert motion under Federal Rule of Evidence 104(a)

to exclude Dr. Hayes’s witness statement. Although Mr. Mathis points to a belated

objection he made to Dr. Hayes’s pre-filed witness statement, the district court correctly

concluded Mr. Mathis could not object to this evidence after it had already been admitted.

       After denying Mr. Mathis’s belated objection, the court recognized Dr. Hayes as

an expert in biomechanical engineering. The court instructed Mr. Mathis’s counsel to

object if he “believe[d] that the testimony either as designated or as elicited exceed[ed]

the scope of [Dr. Hayes’s] qualifications given his training and education as an anatomist

and a biomechanical engineer.” Trial Tr., Vol. VI at 1338. Mr. Mathis did not make any

specific objections at trial to such testimony. Further, Mr. Mathis does not argue the

court plainly erred in admitting Dr. Hayes’s testimony. Somerlott v. Cherokee Nation

Distribs., Inc., 686 F.3d 1144, 1151 (10th Cir. 2012) (“The burden of establishing plain

                                            -19-
error lies with the appellant.”). “[T]he failure to argue for plain error and its application

on appeal . . . surely marks the end of the road for an argument for reversal not first

presented to the district court.” Richison, 634 F.3d at 1131. Accordingly, we deem Mr.

Mathis’s challenge to Dr. Hayes’s testimony forfeited.

                           C. Denial of Motion for New Trial

1. Standard of Review

       We review the denial of a motion for a new trial for abuse of discretion. Minshall

v. McGraw Hill Broad. Co., Inc., 323 F.3d 1273, 1283 (10th Cir. 2003). We also review

a district court’s denial of a motion to recuse or disqualify a judge for abuse of discretion.

United States v. Mendoza, 468 F.3d 1256, 1262 (10th Cir. 2006) (explaining the standard

of review in the context of a 28 U.S.C. § 455(a) motion). 8 “[A] court abuses its

discretion only when it makes a clear error of judgment, exceeds the bounds of

permissible choice, or when its decision is arbitrary, capricious or whimsical, or results in

a manifestly unreasonable judgment.” Queen v. TA Operating, LLC, 734 F.3d 1081,

1086 (10th Cir. 2013) (quotations omitted).

2. Analysis

       Mr. Mathis argues the law clerk’s husband’s representation of AIG created a

conflict of interest under Canon 3(F) of the Code of Conduct for Judicial Employees or

an appearance of partiality under 28 U.S.C. § 455(a), and that the district judge’s failure

       8
         On appeal, Mr. Mathis does not specifically ask for recusal of the district judge.
Instead, he requests only that we vacate the judgment and remand the matter for a new
trial before a jury.

                                             -20-
to screen her law clerk adequately from the case requires vacating the judgment and

remanding for a new trial. We conclude the district court did not abuse its discretion in

denying Mr. Mathis’s motion for a new trial because there was no actual conflict under

Canon 3(F) or appearance of impropriety based on the record under § 455(a) and relevant

case law to justify reversal. 9

       a. Canon 3(F) of the Code of Conduct for Judicial Employees

       The Code of Conduct for Judicial Employees sets forth specific rules governing

law clerk conflicts of interest. See Code of Conduct for Judicial Employees § 320, Canon

3. 10 Three provisions in Canon 3(F) are potentially pertinent here. Canon 3(F)(2)(a)

provides, in relevant part, that law clerks should not perform any official duties in any

matter in which they know their spouse (1) “has a financial interest in the subject matter

in controversy or in a party to the proceeding,” Canon 3(F)(2)(a)(iii); (2) “is acting as a


       9
          As the parties acknowledge and pertinent cases illustrate, the relevant time frame
for analyzing the law clerk’s role in this case began when she learned her husband and his
firm were retained to monitor the trial. See Milgard Tempering, Inc. v. Selas Corp. of
Am., 902 F.2d 703, 713-714 (9th Cir. 1990) (holding § 455(a) did not require recusal of a
district judge whose law clerk received a job offer from the plaintiff’s law firm while the
case was pending because the judge screened the law clerk from the case immediately
after the firm contacted the clerk); Hunt, 783 F.2d at 1016 (holding a district judge did
not abuse his discretion in denying a recusal motion when two of his law clerks accepted
job offers from a law firm representing several defendants in the case because one law
clerk had no involvement and the other law clerk was removed from the case as soon as
he accepted a job with the firm).
       10
         The Code of Conduct for Judicial Employees took effect on January 1, 1996.
See Code of Conduct for Judicial Employees § 310.20(b). It applies to all judicial branch
employees except judges, Justices, and employees of certain federal agencies and offices,
who are subject to a separate code of conduct. See id. § 310.10(a).

                                            -21-
lawyer in the proceeding,” Canon 3(F)(2)(a)(iv)(B); or (3) “has an interest that could be

substantially affected by the outcome of the proceeding,” Canon 3(F)(2)(a)(iv)(C). As

we explain below, the law clerk did not have a conflict under Canon 3(F).

       First, the law clerk’s husband did not have a “financial interest in the subject

matter in controversy or in a party to the proceeding.” Canon 3(F)(2)(a)(iii). Mr. Mathis

raises this issue for the first time on appeal and does not argue plain error, which alone is

a ground for rejecting his argument. See Mendoza, 468 F.3d at 1262. It fails in any

event. Although not well developed, Mr. Mathis’s argument appears to be that the

clerk’s husband had a “financial interest in the subject matter in controversy” because

AIG paid him to monitor the trial. This misunderstands what constitutes a financial

interest under the Code. The Code defines “financial interest” as “ownership of a legal or

equitable interest, however small, or a relationship as director, advisor, or other active

participant in the affairs of a party.” Canon 3(F)(4). The clerk’s husband’s arrangement

with AIG and his monitoring role in the case do not fit within this definition.

       Second, the law clerk’s husband was not “acting as a lawyer in the proceeding.”

Canon 3(F)(2)(a)(iv)(B). Although AIG retained him and his firm for legal services, they

were not retained to represent a party in the Mathis case. Neither the clerk’s husband nor

anyone from his law firm entered an appearance in the case. His firm only monitored the

trial for AIG, which was not a defendant and had no presence in the trial. Mr. Mathis’s

attempt to stretch “acting as a lawyer in the proceeding” to include monitoring a trial on

behalf of a client who is not a party to the case lacks any authority or reasonable basis.

                                             -22-
       Third, Mr. Mathis did not argue in either the district court or on appeal that the law

clerk’s husband had “an interest that could be substantially affected by the outcome of the

proceeding.” Canon 3(F)(2)(a)(iv)(C). We need not address this provision due to Mr.

Mathis’s failure to alert the district court or this court to its possible application. In any

event, it is far too speculative to discern any interest the clerk’s husband may have had in

the proceeding.

       We conclude the law clerk did not have a conflict under the Code.

       b. Appearance issue

       Even if there was no conflict under the Code of Conduct for Judicial Employees,

Mr. Mathis contends the law clerk’s presence created an appearance of partiality under 28

U.S.C. § 455(a).

              i.   28 U.S.C. § 455(a)

       Section 455(a) states a judge “shall disqualify himself in any proceeding in which

his impartiality might reasonably be questioned.” 28 U.S.C. § 455(a). The purpose of

§ 455(a) is “to promote confidence in the judiciary by avoiding even the appearance of

impropriety whenever possible.” Liljeberg v. Health Servs. Acquisition Corp., 486 U.S.

847, 866 (1988).

       “Section 455 contains an objective standard: disqualification is appropriate only

where the reasonable person, were he to know all the circumstances, would harbor doubts

about the judge’s impartiality.” In re McCarthey, 368 F.3d 1266, 1269 (10th Cir. 2004);

see also Liljeberg, 486 U.S. at 859-60. “In conducting this review, we must ask how

                                              -23-
these facts would appear to a well-informed, thoughtful and objective observer, rather

than the hypersensitive, cynical, and suspicious person.” Sensley v. Albritton, 385 F.3d

591, 599 (5th Cir. 2004) (quotations omitted); see also In re Sherwin-Williams Co., 607

F.3d 474, 478 (7th Cir. 2010). The reasonable observer is not the judge or even someone

familiar with the judicial system, but rather an average member of the public. See United

States v. DeTemple, 162 F.3d 279, 287 (4th Cir. 1998).

              ii. Law clerk and judge appearance issues

       “Even if the judge has no reason to recuse herself based upon her own

circumstances, a law clerk’s relationships might cause the impartiality of decisions from

that judge’s chambers in which the clerk participates reasonably to be questioned.”

Hamid v. Price Waterhouse, 51 F.3d 1411, 1416 (9th Cir. 1995). Of course, “[i]f a clerk

has a possible conflict of interest, it is the clerk, not the judge, who must be disqualified.”

Hunt v. Am. Bank & Trust Co., 783 F.2d 1011, 1016 (11th Cir. 1986); see Hamid, 51 F.3d

at 1416 (determining that because the law clerk “had no involvement in the case at

bar . . . [a] reasonable person knowing all the facts regarding [the law clerk’s]

relationship with the [defendant’s] firm . . . would not conclude that the impartiality of

[the judge’s] decisions in the case should be questioned”); Byrne v. Nezhat, 261 F.3d

1075, 1100-02 (11th Cir. 2001) (holding a district judge did not abuse his discretion in

declining to recuse himself from a case when he screened his law clerk who had

previously worked for one of the law firms representing a party in a case). If a law clerk

continues to work on the case in which his or her impartiality might reasonably be

                                             -24-
questioned, however, the clerk’s actual or potential conflict may be imputed to the judge.

See Hall v. Small Bus. Admin., 695 F.2d 175, 180 (5th Cir. 1983).

       Although determining whether there is an appearance problem under § 455(a) is a

fact specific inquiry, cases addressing motions to recuse judges under § 455(a) based on

their law clerks’ relationships are instructive. In Hall, a magistrate judge’s law clerk

accepted a position with the plaintiff class’s firm while she was working on the case for

the judge, including drafting the opinion. 695 F.2d at 177-78. The judge stated he had

already made his decision before the law clerk had drafted the order, and in his words, the

law clerk was “little more than an amanuensis in the case.” Id. The Fifth Circuit

reversed and vacated the judgment because “[w]hether or not the law clerk actually

affected the magistrate’s decision, her continuing participation with the magistrate in a

case in which her future employers were counsel gave rise to an appearance of partiality.”

Id. at 179.

       Similarly, in Parker v. Connors Steel Co., 855 F.2d 1510, 1523-25 (11th Cir.

1988), the Eleventh Circuit found a district judge had an appearance of partiality because

his law clerk’s father was a senior partner at a law firm representing the defendants in a

civil case and the law clerk assisted in preparing the court’s order granting summary

judgment to the defendants. Id. The relationship between the law clerk and defense

counsel was compounded by the facts that the judge credited the law clerk’s work in a

footnote appearing in the summary judgment order, the law clerk had held a hearing on

the summary judgment motion outside the judge’s presence, and the law clerk’s father

                                            -25-
was a former law clerk to the judge. Id. Even so, the Eleventh Circuit held the judge’s

failure to recuse himself was harmless error because the court reviewed the district

court’s grant of summary judgment de novo and determined summary judgment was

proper, and because denying relief would not result in injustice in other cases or

undermine the public’s confidence in the judicial process. Id. at 1526-27.

       In Hamid, the Ninth Circuit concluded a district court did not abuse its discretion

in denying a motion for recusal. 51 F.3d at 1416. Plaintiff’s counsel moved to recuse the

district judge in a civil case after learning one of the judge’s law clerks previously had

worked for a law firm that had represented two of the defendants in a related criminal

case. Id. The law firm also had accepted service on behalf of the defendants in the civil

action. Id. Although the law clerk had performed extensive work on the case for the

district judge, the Ninth Circuit concluded the clerk was not required to be screened from

the case. Id. at 1416-17. It reasoned the law firm did not appear on behalf of anyone in

the case and the law clerk was not aware the firm represented any of the defendants in

matters related to the case. Id. at 1417. The court noted that an appearance of partiality

does not exist merely by drawing “a line . . . connecting a person within chambers to a

person or firm related, no matter how remotely, to a party in the case.” Id. 11



       11
         The plaintiff also moved to recuse the judge because her other law clerk went to
work for a law firm representing one of the named defendants in the action following his
clerkship. The Ninth Circuit affirmed the district court’s denial of the recusal motion
based on this clerk’s conflict because the clerk did not work on the case or discuss it with
the judge. Hamid, 51 F.3d at 1416.

                                            -26-
       In United States v. Martinez, 446 F.3d 878 (8th Cir. 2006), the Eighth Circuit

concluded a district judge’s recusal was not required from a criminal case in which her

law clerk had previously assisted in the defendant’s prosecution while working at the

U.S. Attorneys’ Office. Id. at 883. The law clerk had been screened from the judge’s

criminal docket, but due to short staffing served as a courtroom deputy during a hearing

on the defendant’s motion to withdraw his guilty plea. Id. at 881. The court denied the

motion, and the defendant filed a motion to recuse the judge from sentencing. Id. The

Eighth Circuit decision explained that an average observer who knew all of the facts

would not question the judge’s impartiality given that the law clerk was screened from

the case and performed only ministerial duties at the hearing. Id. at 883.

              iii. Analysis

       Although none of these cases is on all fours with the facts before us, they provide

useful guideposts. On a spectrum, Hall and Parker would fall on the more serious end of

possible appearance issues based on law clerks, and Martinez and Hamid would land on

the other. The facts before us are closer to Martinez and Hamid, both of which did not

find judicial recusal was warranted under § 455(a).

       Unlike the law clerk in Hall, the law clerk in this case, according to the judge, did

not have continuing substantive participation in the case after the potential appearance

issue was brought to the law clerk’s and judge’s attention. Unlike the law clerk in

Parker, the clerk in this case, according to the judge, did not assist the court in preparing




                                             -27-
the dispositive order in the case. Unlike in both Hall and Parker, neither the clerk’s

husband nor his law firm represented a party in the case.

       Like the law firm in Hamid, the law clerk’s husband’s law firm did not appear on

behalf of anyone in the case and was even further removed than the law firm in Hamid.

And like the law clerk in Martinez, the clerk in this case, according to the judge,

performed only ministerial acts at the trial.

       With these cases in mind, we consider more specifically whether the

circumstances of the law clerk and her husband warrant reversing the district court’s

denial of Mr. Mathis’s motion for a new trial. Before we do, we emphasize that our

review of this issue is constrained not only by the abuse-of-discretion standard of review

but especially by the record on appeal. Nothing in the record controverts the district

court’s statements that (1) the law clerk performed only ministerial functions after her

husband started monitoring the trial, and (2) she did not participate in drafting the post-

trial findings and conclusions. Under these facts, we cannot say the district court abused

its discretion in denying the motion for a new trial.

       First, the law clerk’s husband did not represent a party in the case or have a

financial interest in its outcome. Moreover, in light of the husband’s attenuated

monitoring role, see Hamid, 51 F.3d at 1417, Mr. Mathis has not explained how a

reasonable observer would believe the impartiality of the court’s decision might

reasonably be questioned based on the law clerk and her husband’s relationship. We do

not see how he could do so in light of the next point.

                                                -28-
         Second, the law clerk informed the judge of her husband’s monitoring role as soon

as she became aware of it, and from that point the record before us shows she had no

further substantive involvement with the case. See Martinez, 446 F.3d at 883. In her

order denying Mr. Mathis’s request for a new trial, the judge stated her law clerk “was

not involved in the case after this point beyond a ministerial and observational role.”

App. at 153. The judge said she drafted the findings of fact and conclusions of law

herself based on the record and her personal notes, and the clerk took no part in drafting

or researching the opinion. Mr. Mathis did not ask for a hearing in district court to

explore the facts further or contest them on this issue. As noted above, we may review

only the record presented to us.

         Although it would have been better for everyone involved if the judge had

promptly disclosed the law clerk and her husband’s relationship to the parties and if the

clerk had stopped attending the trial, a reasonable observer who was fully informed of the

facts based on the record before this court would not question the judge’s impartiality.

See Liljeberg, 486 U.S. at 859-60. Those facts indicate that, as soon as the law clerk

became aware of her husband’s situation, she informed the judge, who screened her from

substantive work on the case. See DeTemple, 162 F.3d at 286 n.2 (holding that a judge

did not abuse his discretion in declining to recuse himself from a criminal case in which

his law clerk was married to the prosecutor because the clerk was screened from the

case).




                                            -29-
       Accordingly, the district court did not abuse its discretion in denying the motion

for a new trial. 12

                                   III CONCLUSION

       Based on the foregoing, we affirm the district court’s judgment.




       12
          At oral argument, Defendants argued for the first time that because Mr. Mathis
waited for five weeks to file his motion for a new trial in the district court, he did not
timely raise the conflict or appearance issue and we should reject his argument on appeal.
Our cases acknowledge that § 455(a) contains a timeliness requirement to prevent
counsel from waiting until after an adverse ruling to seek recusal. United States v.
Stenzel, 49 F.3d 658, 661 (10th Cir. 1995); Singer v. Wadman, 745 F.2d 606, 608 (10th
Cir. 1984). Given that Mr. Mathis did not learn of the law clerk issue until after trial had
concluded and filed the motion approximately a month later, we decline to decide his
motion was untimely.

                                            -30-
