F OR P UBLICATION



### UNIT E D ST AT E S CO URT O F APPE AL S FO R T H E NINT H CIRCUIT

E S T A T E O F H E

N R Y B A R A B I N ; G E R A L D I N E B A R A B I N , personal representative, Plaintiffs-Appellees
,

v

.

A S T E N J O H N S O N , I N C ., Defendant-Appellant

. N o. 10-36142

D.C. No. 2:07-cv-01454- RSL

E S T A T E O F H E

N R Y B A R A B I N ; G E R A L D I N E B A R A B I N , personal representative, Plaintiffs-Appellees
,

v

.

A S T E N J O H N S O N , I N C ., Defendant
,

and

S C A P A D R

Y E R F A B R

I C S , I N C ., Defendant-Appellant

. N o. 11-35020

D.C. No. 2:07-cv-01454- RSL

OPI NI ONE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 2

A ppeal from the United States District Court

for the W e stern District of W ashing ton Robert S. L asnik, District J udg e , Presiding

Arg ued and Submitted En B anc J une 25, 2013—Seattle, W ashing ton

F iled J anuary

15, 2014

B e fore: Alex Koz inski, Chief J udg e, and Diarmuid F

. O ’Scannlain, M. Marg aret McKeown, W illiam A. F letcher, Richard C. Tallman, J ohnnie B . Rawlinson, J ay S. B y bee, Milan D. Smith, J r., N. Randy Smith, J acqueline H. Ng uy en and Paul J

. W a tford, Circuit J udg es.

Opinion by

J udg e N.R. Smith; Partial Concurrence and Partial Dissent by J udg e Ng uy e n

SUMMARY *

Expert Testim o ny

The en banc cour t vacated the district c ourt’s judg ment, and remanded for a new trial based on its determination that the district court failed to make f inding s of relevancy a

nd relia b i l ity b efore a dmitting into evidence certain ex pert testimony
, and that this er ro r re s ulted in prejudice to the defendant.

* T h is su m m ary co n stitu

tes n o part o f th e o p in io n o f th e co u rt. It h as b een p rep ared b y

co u rt staf

f f o r th e co n v en i en ce o f

th e read er.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 3

The en banc court he l d t h a t the district court abused its discretio n by failing to make appropriate g ateway determinations under D a ubert v. Merrell Dow Pharm., Inc.
, 509 U.S. 579 (1993), and F ederal Rule of Evidence 7 02, when it admitted ex pert testimony at trial. The en banc court

c o n d ucted h armless error review by asking if erroneously admitting or ex cluding the evidence affected the outcome of the trial. The en banc court held that the e rror was prejudicial because the erroneously admitted evidence was ess e n t ial to the defendants’ case.

The en banc court held that a reviewing cour t h as the autho r ity to make Daubert finding s based on the record established by the district court, a nd overruled Mukhtar v. California State University
, 299 F .3d 1053, 1066 n.12 (9th Cir. 2002), amended by 319 F

. 3d 1073 (9th Cir. 2003), to the

ex tent that it required that D aubert finding s alway s be made by the district court. T he en banc court concluded t h a t t h e record before the en banc court was too sp a r s e to determine whether the ex pert testimony was releva n t and r eliable, a nd remanded for a new trial.

J udg e Ng uy en, joined by J udg es McKeown, W

. F letcher, B y bee, and W a tford, concurred in part and dissented in part. J udg e Ng uy en concurred in Part I of the majority ’s opinion, which c oncluded that the district c ourt failed to fulfill its
g atekeeping functi o n with reg ard to the ex pert testimony at issue, and ag re e d that the court was unable to determine on t h e current record whether the ex pert testimony was admissible. J udg e Ng uy en d issented with the majority ’s application of harmless error review, and would conditionally
vacate the judg ment and remand with instructions to conduct

a Daubert analy sis in the first instance.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 4

COUNSEL

Michael B

. K ing (arg

ued) and Emilia L

. Swee n e y , Carney B adley Spellman P.S., S eattle, W ashing ton, f or D efendantAppellant AstenJ ohnson.

Mary H. Spillane and Daniel W

. F erm, W illiams, K astner & Gibbs PL L C, Seattle W ashing ton, f or Defend a nt-Appellant Scapa.

Cameron O. Carter, B ray

ton Purcell L L P, Portland, Oreg on; P h i l i p A

. T a l m a d g e ( a r g u e d ) a n d S i d n e y T r i b e, Talmadg e/F itz patrick P L L C
, T u k wila, W ashing ton; and Alan R. B ray ton, Gilbert L

. P u r c e l l
, L loy d F

. L eRoy
, J ames P. Nevin, and Richard M. Grant, B r ay ton Purcell L L P, Novato, California, for Plaintiffs-Appellees.

OP INION

N.R. SMI TH, Circuit J udg e :

This case requires us to once ag ain consider the d istrict court’s a dmission of e x pert testimony a t trial. W e review the admission of ex pert testimony at trial for a n abuse o f discretion. Primiano v. Cook
, 598 F .3d 5 5 8
, 5 6 3 ( 9th Cir. 2010). I f the d i strict c o u rt improperly admitted the ex pert testimony
, we apply harmless error r eview to determine whether its decision m u s t be reversed. United States v

. Laurienti
, 611 F .3d 530, 547 (9th Cir. 2010). W hen we find the erroneous a d mission of evidence actually p rejudiced the defen d a n t , such that the error was not harmless, the appropriate remedy is a n e w t r i al. See United States v

. 4.85 Acres o f Land
, 546 F .3d 613, 6 20 ( 9th Cir. 2008). Apply ingE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 5

this well-settled precedent to the facts of this case, we vacate the judg ment and remand for a new trial. 1

F ACTS

Henry Barabin worked at Crown-Z ellerbach paper mill from 1968 u ntil h is retirement in 2001. I n the mill, CrownZ e ller b a c h shredded log s into chips and then ex posed the chips to corrosive chemicals a nd hig h pressure to create paper slurry

. Paper slurry is ninety -nine percent wat e r a n d o ne percent pulp fi b e r

. The mill produced paper by removing

w a ter from the paper slurry

. A s part of that proces s , m a c h i n es p ulled the paper throug h dry ers. Dry er felts h eld the paper ag ainst the d

ry ers, so that the paper would dry properly

. AstenJ ohnson, I nc. and Scapa Dry er F abrics, I nc. supplied the mill with dry er felts that contained asbestos.

B a rabin had a v ariety of jobs d uring the time h e worked
at the mill. He started a s a paper sor t e r , w orking in a different building than where the dry e r s were located. He then moved to the technical department, where h e worked a s

a pulp tester and a paper tester. O n o ccasion, he worked at a test station that was about twenty feet from the dry e rs. After working in the technical department, he went to work on the
paper machines. Part of his job was to clea n the d ry ers. However, these jobs were n ot his only ex posure to the dry er felts; he also too k p i e c e s o f dry e r felt home to use in his
g arden.

1 B ecau se w e f

in d th e erro n eo u s ad m issio n o f ex p ert testim o n y w arran ts

a n ew trial, w e d o n o t ad d ress th e m erits o f t h e o t h er arg u m en ts raised b y A sten J o h n so n

an d Scap a.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 6

I n 2 006, B arabin w as diag nosed w ith pleural malig na n t epithelial mesothelioma (“mesothelioma”). Mesothelioma is

a rare cancer that affects the tissue surrounding the lung s. Alleg ing that this occupational ex p osure to asbestos f rom the dry e r f e lts caused his mesothelioma, Henry B arabin a nd Geraldine B arabin, his wife, b r o u gh t s uit ag ainst AstenJ ohnson and Scapa.

All parties ag re e , a

nd the science makes clear, that asbestos e x p osure from inhaling r espirable f ibers can cause mesothelioma. A t trial, the parties a rg ued over whether

ex p osure to the dry e r felts (pr o v i d ed by AstenJ ohnson a nd Scapa) substantially contributed to B arabin’s mesothelioma. Of necessity
, the case w as to be a battle of the ex perts. B oth parties had ex p erts who were p r epared to testify in support o f their arg uments.

Two of the B arabins’ e x perts were Kenneth Cohen a nd Dr. J ames Millette. Mr. Cohen had been em p loy ed in the industrial hy g iene field for several d ecades. He had also taug ht industrial tox icolog y courses at a u niversity

. Dr. Millette had been involved in asbestos related research since 1974. He published a number of artic l es dealing with asbestos, including an article dea ling with asbestos fiber release from dry

er felts.

Prior to trial, AstenJ o hnso n and Scapa filed motions in li mi n e to ex c lude Mr. Cohen and Dr. Millette as ex pert witnesses

. A s t enJ ohnson arg ued that Mr. Cohen w as not qualified to testify as an ex pert and that his theory was not the product of scientific methodolog y

. AstenJ ohnson and Scapa
arg ued that Dr. Millette ’ s tests w ere unreliable, because his methodolog y was not g ener a l l y accepted in the scientific community

. They a lso arg u ed that the disparity between hisE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 7

tests and the conditions at the mill was so g reat that hi s testimony would not help the jury . The motions also soug ht
to ex clude testimony from any ex pert r eg arding the theory that “every

asbestos fiber is causative.”

After receiving the motions, and without a Daubert 2 hearing
, the distri c t c o urt ex cluded Mr. Cohen as a witness because of his “dubious credentials and his lack of ex pertise with reg a rd to dry er f

elts and paper mills.” T he district court also had concerns with D r. Millette’s testimony

. Specifically
, the district court was “ troubled by the marked d i f f e r ences between the conditions o f Dr. Millette’s t e sts and the actual conditions at the [ mill] .” Nonetheless, the district court ruled that D r. Millette could testify provided the jury was informed his tests were “performed under laboratory conditions which are not the same as conditions at the [ mill] .”

As to the “every ex p osure” theory
, the district court f ound “a strong divide among both scientists and courts” on whether it is relevant in asbestos cases. However, “[ i] n the interest o f allowing each party to try its case to the ju r y ,” the district court allowed the testimony

.

The B arabins then filed a motion to request a pretrial D a u bert h earing reg arding Mr. Cohen. At a pretria l confe re n c e, the district c ourt rejected the B arabins’ request for a D a u b ert hearing

. I nstead, it reversed its d ecision to

ex c lude Mr. Cohen’s testimony

. The district co u r t’s only

ex p lanation for why it reversed its decision was t h at the B arabins “ did a much better j o b ” in their motion “of presenting

. . . th e f

u l l f actual basis behind Mr. Cohen testify ing and his testimony in other cases.”

2 Da u b ert v. Merrell Do w Ph arm., In c. , 5 0 9 U.S. 5 7 9 (1 9 9 3 ).E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 8

At trial, numerous ex perts testified. B oth Mr. Cohen a nd D r

. Millette testified. Dr. B rodkin, another ex pert, al s o testifi ed f o r the B arabins. Part of Dr. B rodkin’s testimony

was about the “every ex posure” theory

. As each of t h e s e

ex p erts testified, AstenJ o h n son and Scapa objected to their testimony . The district court overruled the objections.

P ROCEDURAL HISTORY

A f ter the B arabins presented their case at tria l
, AstenJ ohnson and Scapa filed motions for judgm ent as a matter of law. AstenJ ohnson an d S c a pa believed they were entitled to judg ment a s a matter o f law, because the B arabins had failed to show that their companies had manufactured the dry er felts to whic h Ba r a b in had been ex posed. I n the alternative, they arg ued that the B arabins had failed to demonstrate a c ausal link b etween th e d ry er felts a nd B arabin’s mesothelioma. The district co u rt d enied the motions. AstenJ ohnson and Scapa r enewed their m o t i o ns after closing arg uments. The district court denied the motions ag a in.

After deliberations, the j u r y found in favor of the B arabins and awarded damag es totaling $10,200,000. The district court g ranted AstenJ ohnson’s and Scapa’s motions to vacate the judg ment and scheduled a reasonableness hearing

. The district court found the damag es award to be reasonable, offset the judg ment b y a total of $836,114.61, 3 an d entered

3 T h e B arab in s h ad p rev i o u sly settled w it h a n u m b e r o f th ird p arties. W ash i n g to n law req u ires th e co u rt to o f f s et t h e j u d g m en t b y th e a m o u n t

o f su ch settlem en ts, u n less th e settlem en ts w ere u n reaso n ab le. S ee W ash

. Rev . Co d e § 4 .2 2 .0 6 0 (2 ).E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 9

judg ment in favor o f t h e B a rabins in the a mount o f $9,373,152.12.

B o t h Scapa a

nd AstenJ ohnson then filed motions for a

new trial or, in the alternative, for a remittitur. One o f the
g rounds o n which Scapa a n d AstenJ ohnson soug ht a n e w trial

was the improper admission of ex pert testimony

. The district court denied the motions in their entirety

.

AstenJ ohnson and Scapa filed timely no t ices of appeal. A three-judg e panel consolidated the appeals. I t unanimously held that the district court abused its discretion by failing to make the necessary relevancy and reliability finding s under Daubert

. The panel rema n d e d f o r a new trial pursuant to Mukhtar v

. California State University
, 299 F. 3 d 1053 (9th Cir. 2002), amended by 319 F

. 3d 1073 (9th Cir. 2003). The B arabins petitioned this Court to rehear the c ase en banc, a nd

a majority o f non-recused active judg es voted t o rehear the

case.

STANDARDS OF REVIEW

“A district court’s evidentiary rulin gs should not be reversed abs e n t c lear abuse of discretion a nd some prejudice.” Gran d Ca n

y on Skywalk Dev., LLC v. ‘Sa’ Nyu W a Inc.
, 715 F .3d 1196, 1202 (9th Cir. 201 3 ) (internal quotations and citation omitted). However, w e review de

novo the “construction or interpretation of

. . . th e Fe d e ral Rules of Evid ence, including w hether particular evidence falls within the scope of a gi v e n ru le.” United States v

. Durham
, 464 F .3d 976, 981 (9th Cir. 200 6 ) (citations omitted). A ruling on a motion for new trial “ will be overturned on appeal only for abuse o f d iscretion.” Kode v

. Carlson
, 596 F .3d 608, 611 (9th Cir. 2010) (citation omitted).E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 10

D ISCUSSION

I.

Rule 702 of t he F ederal Rules of Evidence g overns admission of ex p ert testimony in the federal courts:

I f scientific, technical, o r other specializ e d knowledg e will assist the trier of f act to understand the evidence o r to determine a fact in issue, a w itness qualified as an ex pert b y knowledg e, skill, ex perience, training
, o r education, may testify thereto in the form o f

an opinion or otherwise, if (1) the testimony is bas e d upon sufficient facts or data, (2) the testimony is the product o f reliable principles and methods, and (3) the witness has applied the principles and methods r e l i a bly to the facts of the case.

F ed. R. Evid. 702 (2010). 4 W e have interpreted Rule 702 to require that “[ e] x pert testimony

. . . be both relevant a nd reliable.” United States v. Vallejo
, 237 F .3d 1008, 1 019 (9th Cir. 2001). Relevancy simp l y requires that “[ t] he evidence

. . . lo gi c a l ly advance a material aspect of the party ’s case.” Cooper v. Brown , 510 F .3d 870, 942 (9th Cir. 2007).

The issue here is reli ability : whether an e x pert’s testimony has “a r e liable basis in the k nowledg e a

nd

ex p erience o f the relevant discipline.” Kumho Tire Co., Ltd.

v. C a r m i chael
, 526 U .S. 137, 149 (1999) (citation a nd

4 T h e trial in th i s case to o k p l ace b ef o re t h e Fed eral R

u les o f Ev id en ce

w ere resty led in 2 0 1 1

.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 11

alterations omitted). The “ evidentiary r e l iability [ is] based
upon scientific validity .” Daubert , 509 U.S. at 590 n.9. W e

are concerned “not [ wi t h ] the correctness of the e x pert’s conclusions b ut the soundness of his methodolog y

. ” Primiano v. Cook
, 598 F .3d 558, 564 (9th Cir. 2 010) (citations and quotations o mitted). The duty falls s quarely
upon the district court to “ act as a ‘g atekeepe r ’ t o ex clude junk science that does n ot meet F ederal Rule of Evidence 702’s reliability standards.” E llis v. Costco W holesale Corp.
, 657 F .3d 970, 982 (9th Cir. 2011).

The reliability inquiry is “a f l e x i b l e one.” Kumho Tire
, 526 U.S. at 150. T he Supreme Court has sug g ested several factors that c an be used to determine the reliability of ex pert testimony : “1) whether a theory o r technique can be tested; 2 ) whether it has b een subjected to peer review and publication; 3) the known or potential error rate o f t h e theory o r technique; and 4) whether the theory o r technique enjoy s g eneral acceptance w ithin the relevant scientific comm u n i t y

. ” United S tates v. Hankey
, 203 F

. 3d 1160, 1167 (9th Cir. 2 000) (citing Daubert
, 509 U.S. a t 592–94). However, w het her these specific factors are “reasonab le measures of reliability in a particular case is a m a t t e r t h at the law g rants the trial judg e broad latitude to d etermine.” Kumho Tire
, 526 U.S. at 153.

The trial judg e also has broad latitude in determining the
ap p r o p riate f

orm of the inquiry

. See United States v

. Alatorre
, 222 F .3d 1098, 1102 (9th Cir. 2000) (“Nowhere

. . . does the Supreme C ourt mandate the form that the inquiry into r elevance and reliability must take.”). W hile pretrial

“ Daubert hearing s” are commonly used, see, e.g. , Uni ted States v. Lukashov
, 694 F .3d 1107, 1112 (9th Cir. 2012), theyE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 12

are certainly not required, United States v. Jawara
, 474 F .3d 565, 582 (9th Cir. 2006).

Nevertheless, Rule 702 “clearly contemplate s some deg ree of reg u lation of the subjects and theories about which

an ex pert may testify .” Daubert
, 509 U.S. at 589 (emphasis added). Apply ing these principles to the facts before us, we find the d istrict court abused its discretion by failing to make appropriate determinations u n d e r D aubert and F ederal Rule of Evidence 702.

The dis trict c ourt f

irst ex cluded Mr. Cohen’s testimony based o n his “dubious credentials and lack of ex pertise.” The district court’s only ex plan at i o n for r eversing its decision, without a Daubert hearing o r f i nding s, was, “I think the plaintiffs did a much better job of presenting to me the full factual b asis behind Mr. Cohen testify ing and hi s t e s timony i n o t h er cases.” Absent from the ex planation is any indication that the district court a ssessed, or made finding s reg arding
, the scientific validity or meth o d olog y of Mr. Cohen’s proposed testimony

. T herefor e , the d istrict court failed to assume its role as g ate k e eper with respect to Mr. Cohen’s testimony

.

The d istrict court also f

ailed to act as g atekeeper for Dr. Millette’s testimony

. After acknowledg ing v arious
arg uments a s to whether the testimony was admi s s ible, the district c ourt concluded that it could b e ad mitted, so long a s the jury w as informed of the “marked d ifferences ” b etween conditions of the tests an d t h e actual conditions o f the mill. Rather than making f

inding s of relevancy and r eliability
, the district court passed its g reatest concern about Dr. Millette’s testimony to the jury

to determine.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 13

The district court took the same a pproach with r espect to

ex p ert testimony

reg arding the “every

ex posure” theory :

There is obviously a strong divide among both

s c ientists and courts on whether such ex p er t t e s timony is relevant to asbestos-related

cases. In the interest of allowing each party
to try its case to the jury
, the C o u r t deems admis s ible ex p ert testimony that every

ex p osu re can cause an asbestos-related disease.

(emphasis added). J ust as the dist r i ct court cannot a bdicate its role as g atekeeper, so too must it avoid deleg ating that role to the jury

.
Here, the district court d eleg ated that role by g iving e ach side leeway to present its ex pert testimony to the jury

. B efore allowing the jury to hear the ex pert testimony
, the district
court should have first determined that the “ex p ert meets the threshold established b y Rule 702,” Prim i ano , 598 F .3d at 564–65; that is the entire purpo s e o f Daubert

. The district
court abused its discretion by a dmitting the ex pert testimony without first finding it to be rel e v ant and reliable under Daubert

.

II.

W h en we conclude evidence h a s b een improperly admitted, “we consider whether the error w a s harmless.” United States v. Bailey
, 696 F .3d 794, 802–03 (9th Cir. 2012). W e treat the erroneous a d mission of ex pert testimony the

same as all other evidentiary errors, by subjecting i t to harmless error review. See United States v. Rahm , 993 F .2dE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 14

1 4 0 5
, 1 415 (9th Cir. 1 993). We reverse “only if the erro r affect[ ed] a s u b s tantial r ig ht of the party .” F ed. R. Evid. 103(a). “I n o ther words, we require a findi n g of prejudice.” Obrey v. Johnson , 400 F .3d 691, 699 (9th Cir. 2005).

“[ T] he burden [ is] on the beneficiary of the error either to prove that there w a s n o injury or to suffer a reversal of his

erroneou s l y obtained judg ment.” Id. at 700 (citation omitted). Thus, “we beg in with a presumption of prejudice. That presumption can be rebutted by a showing that it is more probable than not that the jury would h ave reached the same verd i c t even if the evidence had not been admitted.” Jules Jordan Video, Inc. v. 144942 Canada Inc.
, 617 F .3d 1146, 1159 ( 9 th Ci r

. 2 0 10) (citation and internal quotations omitted).

As the b eneficiaries of the erroneously admitted evidence, the B arabins fail to rebut the presu m p t i o n of prejudice. I ndeed, they admit they cannot win without this e x p er t t estimony

. 5 Prejudice is at its a pex when the district court erroneously admits evidence that is critical to the proponent’s

case. The improper admissio n o f the ex pert testimony severely p rejudiced A s t e n J ohnson and Scapa because the B arabins’ clai m depended wholly u pon the erroneously admitted evidence. G iven these c i rcumstances, there is no doubt the error was not harmless.

5 A t least tw ice d u rin g th e en b an c o ral arg u m en ts th e B arab in s ad m i tted th ey d id n o t h av e a case w ith o u t th i s ex p ert testim o n y

. First, th e B arab in s ’

co u n sel stated t

h at, i f th e d i strict j u d g e f o u n d th e e x p ert testim o n y in ad m issib le (sp ecif

ically t h e testim o n y o f Dr. Millette), th e resu l t w ou ld b e “ a j u dg m en t in f

av o r o f th e def

en d an ts.” S e c o n d
, in resp o n se to th is Co u rt’ s s u g g estio n th at w ith o u t ex p ert testim o n y it w as “ g am e o v e r ” f or th e B arab i n s, co u n s e l s t a t ed “ I th in k th at’ s rig h t.” Ou r rev iew o f th e

reco rd co n f

irm s th e w isd om

o f th is co n cessio n

.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 15

The dissent contends t hat we must decide whether the evidence would be admissible before e ng ag ing in harmless

error r eview. Dissent at 23. However, the dissent is r eading

a non-ex istent step into our evidentiary -error case law.

The dissen t c ites only two c ases addressing the use o f harmless error revi e w in these circumstances. 6 They both support o ur decision. See 4.85 Acres of Land
, 546 F. 3 d at 620; Simpson v. Thomas , 528 F

. 3d 685, 691 (9th Cir. 2008). I n 4.85 A cres of

Land
, we f

ound that the district court abused its discretion by ex cluding all post-taking sales from consideration without first making any finding s r eg arding the comparability of the e x cluded sales to the condem n ed property

. 546 F

. 3 d at 620. Despite being asked to do so, we refused to address on appeal whether “some of the posttaking comparable sales would have b e e n admissible.” Id. I nstead, we eng ag ed in harmless error review, found that the error was not harmless, and remanded for a new trial. I d.

I n Simpson
, we f

ound that the district court ab u s e d its discretion when it admitted three prior convictions that were

more than ten y ears old without eng ag ing in proper b alancing

6 A ll o f th e o t

h er cases cited by t h e d i s s en t d o n o t ad d ress th is i ssu e. T h ey are n o t cases in w

h ich th e district co u rt f

ailed to an sw er a th resh old
q u estio n o f ad m issib ility

. In stead
, in each of th ose cases (u n l ik e th e case at h an d ), w e w ere task ed w ith d eterm in in g w h eth er ev id en ce w as ad m i ssib le in ord er t o d ecid e if th e d istrict co u rt ab u sed its d iscretio n

. S ee Ba iley
, 6 9 6 F.3 d at 8 0 4

– 0 5 ; Ju les Jo rd a n Vid eo , In c. , 61 7 F

. 3 d at 1 1 5 7

– 5 9 ; La u rien ti
, 6 1 1 F.3 d at 5 47

– 4 9 ; Un ited Sta tes v. Co hen
, 5 10 F.3 d 1 1 1 4
, 1 1 2 7 (9 th Cir. 2 0 0 7 ); Ra h m , 9 9 3 F.3 d at 1 41 5

– 1 6 ; Un ited S ta tes v. Ech a va r ria -Ola r t e , 9 0 4 F.2 d 1 3 9 1
, 1 3 9 8 (9 th Cir. 1 99 0 ). Here, ou r in q u iry in to w

h eth er th e d istrict co u rt ab u sed its d iscretio n en ds w ith ou r d eterm in atio n t

h at it ab d icated its g atek eep i n g resp o n sib ility

. Ho w ev er, to th e ex ten t th at th ese cases ap p ly
, th ey su p po rt o u r d ecisio n

to co n d u ct h arm less erro r rev iew af

ter f in din g th e d istrict co u rt ab u sed i t s d iscretio n

.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 16

under rule 6 0 9(b) of the F ederal Rules o f Evidence. 528 F .3d
at 690–91

. Th e district c o u rt identified the correct rule, but it abused its discretion when it inverted the requirement of the rule, failed to offer specific facts to support it s c o nclusion, and did not find that the p r o b a t ive value substantially outweig hed the prejudice. Id. at 690. W e did not eng ag e in 609(b) balancing o n appeal to determine whether the prior convictions would have been a d m i s sible. I nstead, we went straig ht to h armless error r eview, found the evidence to be prejudicial, and remanded for a new trial. Id. at 690–91.

As both 4.85 Acres of Land and S impson illustrate, when
t h e d i s trict court a

bdicates its responsibility to a nswer a threshold question of admissibility
, we need n o t determine whether the e vidence w ould have been a dmissible before we determine the d istrict court a bused its discretion and proceed
to harmless e rror review. I n bot h c a ses we eng ag e d in harmless error review, as we alway s do, by asking if erroneously admitting or ex cluding the evidence affected the
outcome of the trial. 7 See 4.85 Acres of Land
, 546 F .3d at

7 T h e d i ssen t cites Ha ng a rter v. Pro vid en t Life & A c cid

en t In s

. Co

. , 3 7 3 F.3 d 9 9 8 (9 th Cir. 2 0 0 4 ), to su pp o rt its i d ea o f w

h at co n stitu

t es an ap p ro p riate “ h arm less erro r in q u iry w h en a district co u rt f

ails to f u lf ill its
g atek eep in g f

u n ctio n .” Dissen t at 2 6

. T h is case is in ap p o site; th e d istrict

co u rt in Ha ng a rter d id n o t f ail to f u lf ill its g atek eep in g f

u n ctio n

. W e sp ecif ically h eld th at th e d i strict co u rt “ d id n ot ab u s e i ts d iscretio n in f in d in g [th e ex p ert’ s] testim o n y re l i a b l e b ased o n h is k n ow led g e an d

ex p erien ce” an d th at “ th e d istrict co u rt’ s i n q u iry w as su f f icien t to co m

p ly

w ith its g atek eep in g ro le.” Id

. at 1 0 1 8

.

In stead
, in Ha n g a r t e r , w e rev iew ed f or h arm less erro r th e d istrict

co u rt’ s statem en t th at Da u b ert d id n o t ap p ly

. Id

. (“ W h ile th e d istrict co u rt erred in statin g th at D a u b ert d id n o t ap ply to Caliri’ s n on

- sc i e n t i fi c testim o n y , th at erro r w as h arm less.”). It is d if f icu lt to im ag in e a Da u bert

case th at is less o n p o in t: In Ha n g arter , th e d istrict co u rt said Da u bert didE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 17

620; S i m p s o n , 5 28 F .3d at 691. W e reject the dissent’s attempt to insert a new step into o ur review of evidentiary

errors.

III.

W h en the district co urt has erroneously admitted o r

ex c luded prejudicial eviden c e, w e remand for a new trial. See, e .g. , B. K

.B. v. Maui Police Dep’t
, 276 F .3d 1091, 1109 ( 9 t h Cir. 2 002). W e do so even if the d istrict court er r s b y failing to a n s w er a threshold question of admissibility

. See,
e.g. , 4.85 Acres of Land
, 546 F

. 3d at 620 (ex c l u d i n g other sales without determining comparability ) ; Simpson
, 528 F .3d
at 691 (a d m i t ting convictions w ithout F ederal Rule o f Evidence 609(b) ba l a n cing ). We h a v e no precedent for treating the erroneous admissi on o f ex pert testimony any differently

.

F or seventy y ears prior to Daubert
, the dominant standard for determining admissibility of novel scientific evidence was the “g eneral acceptance” test. Daub e r t , 509 U.S. at 585–86 (citing Frye v. United States , 293 F

. 1013 (D.C. Cir. 1923)). Under Frye
, we required the proponent of n o v e l scientific evidence to “lay a proper fo u n d a t ion” by d emonstrating “g eneral acceptance” of the evidence “in the particular field in w hich it belong [ e d] .” United States v. Boise
, 916 F .2d 497, 503 (9th Cir. 1990).

I n D a u bert
, the Supreme Court set “the standard for admitting ex p ert scientific testimony in a federal t r i a l ” b y holding that the F e deral Rules of E vidence superse d e d t he

n o t ap p ly b u

t w en t o n to m ak e Da u b ert f

in din g s. Here, th e d istrict co u rt said th at Da u b ert

d id ap p ly

b u t f ailed to m ak e Da u b ert

f i n d in g s.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 18

Frye test. Daubert
, 509 U.S. a t 5 8 2, 586–87. Daubert continues to r equire that the prop o n e n t of ex pert testimony lay a proper foundation, but no w lay ing a proper foundation

means establishing relevancy and reliability rather than mere g eneral acceptance. I

d. at 597.

I nitially
, in g rappling with the effe c t s of Daubert
, we remanded two cases to d istr i c t courts to conduct post-hoc Daubert hearing s. See Unite d S t a tes v. Cordoba
, 104 F .3d 225, 229 (9th Cir. 1997); Uni t e d S tates v. Amador-Galvan
, 9 F .3d 1414, 1418 (9th Cir. 1993). 8 A fter the dust of Daubert had settled, we held that an erroneous admission of ex pert testimony
, absent a showing the error was harmless, requires

a new trial. See Mukhtar
, 299 F .3d at 1066–67. To the ex tent Mukhtar requires any

thing more, it is overruled.

AstenJ ohnson and Scapa contend that a r eviewing court should have the a

uthority to make Daubert finding s based on the record established by the district cou r t

. W e ag ree a nd overrule Mukhtar to the ex tent that it req u i r e d that Daubert finding s alway s be made by the district court. See M ukhtar
, 299 F .3d at 1066 n.12. I f the revie w i ng court decides the record is sufficient to determine whether ex pert testimony is

r e l evant and r eliable, it may make such finding s. I f i t “determin es that evidence [ would be inadmissible] a t trial a nd that the remaining
, properly admitted e vidence is insufficient

8 T h ese are n o t cases i n w h ich t h e d istrict co u rt sim

p l y f ailed t o co n d u ct

a Da u b ert h earin g

. In Ama d or-Ga lva n , th e t

rial to o k p lace b ef

ore Da u bert h ad b een d ecid ed
, 9 F.3 d at 1 4 1 6
, so it w o u ld h av e b een im p ossib le f o r th e d istrict co u

rt to m ak e D a u b ert f

in d in g s. Co rd

o b a dealt w ith an issu e of f irst im p ressio n : “ w

h eth er o u r p er s e ru le ex clu d in g t h e ad m i ssio n of

u n stip u lated p o ly g rap h

ev id en ce w as ef

f ectiv ely o v erru led b y D a u b ert .” 1 0 4 F.3 d at 2 2 7

. A f

ter d ecid in g it w as, w e rem an d ed to th e d istrict co u rt to co n d u ct a Da u b ert

h earin g in th e f

irst in s tan ce. Id

. at 2 2 9

.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 19

to constitute a s u b m i s sible case[ ,] ” the r eviewing court may direct e ntry of judg m e n t a s a matter of law. W eisgram v

. Marley Co. , 528 U.S. 440, 446–47 (2000).

C iting W eisgram
, AstenJ ohnson and Scapa a rg u e w e should enter judg ment in this case. W e dec l i n e their invitation. I n W

eisgram
, the Eig hth Circuit found, based on

a fully d evelope d r e cord, that the ex p ert testimony was not reliable. W

e isgram v. Marley Co.
, 169 F .3d 514, 517–18 (8th Cir. 1999). W e ca nnot speak to the admissibility of the

ex p ert testimony at issue here because the record before us is
too spa r se to determine whether the ex pert testimony is relevant and reliable. W e can only say with certainty that the district court erred by

failing to make that determination.

The B arabins and the dissent a r g u e that we should remand for a post-hoc Daubert hearing

. Even assuming that a limited remand is available post- Mukhtar
, see 31 9 F. 3 d at 1074, it would not be a

ppropriate under the circumstances here, where the d istrict court abused its discretion by err o n eously admitting e x pert testimony
, and the evidence was prejudicial. W e therefore remand for a new trial.

CONCLUSION

The district court failed to make finding s of relevancy a nd reliability b efore admitting into evidence the exp ert testimony of Mr. Cohen and Dr. Millette and e x pert testimony reg arding the theory that “every asbestos fiber is causati v e

. ” T he district court’s failure to make these g a teway determinations

was an abuse of discretion. The error was prejudicial because the erroneously admitted e vide nce was essential to the Barabins’ case. Due to the district court’s abdication o f it s role as g atekeeper a

nd the severe prejudice that resulted fromE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 20

the error, the ap p ropriate remedy is a new trial. W e vacate the judg ment and remand for a new trial.

VACATED and REMANDED

. The parties shall bear their own costs on appeal.

Circuit J ud g e N G UYEN
, with whom J udg es M cK EOWN
, W

. F L E T C H E R
, B Y B E E
, and WATF OR D j o i n , c o n c u

r r i n g in part and dissenting in part:

I concur in Part I of th e m ajority ’s opinion, which concludes that the district c ourt fai l ed to fulfill its
g atekee p ing function with reg ard to the ex pert testimony at issue. I al s o a gree w ith the majority that we are unable to determine based on the r ecord before us whether the ex p ert t estimony is admissible. See Maj. Op. at 19 ( “W e cann o t

s peak to the admissibility of the ex p e r t testimony at i s s u e here because the record before us is too sparse to d e t e r mine whether the e x p ert testimony is r e levant and reliable.”). F urther, t o the ex tent the majority overrules Mukhtar v

. California S

tate University
, 299 F .3d 1053 ( 9 t h Cir. 2002),

am e n d e d by 3 19 F .3d 1073 ( 9th Cir. 2003), I am in accord. There is no reason t o r equire a new trial whenever a district
court f ails to conduct a D a u bert analy sis, reg ardless o f wheth er on remand the district court would d etermine that disputed ex pert testimony is relevant and reliable.

I part way s with the majority

, however, in its a pplication of h armless error review. The majority ’s analy sis is seriously flawed because it conflates a district c ourt’s g atekeeping error with a district court’s err o n e ous determination o fE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 21

admissibility

. H e r e , a s s u

m i n g i nadmissibility —a question we cannot answer at this juncture—the majority applies harmless

error review and concludes that a n ew trial is needed because the “ improper admission of the ex pert testimony severely prejudiced [ defendants] .” Maj. Op. at 14 (emphasis added). The majority thus unnecessarily burdens both the parties a nd the judicial sy stem by ordering a new trial w it h o u t h aving a sufficient basis to determi n e w h e ther the disputed ex pert testimony was a d m issible. F urther, the majority ’s approach undercuts its effort to open t h e door to a limited remand occasioned by ove r ruling Mukhtar

. B ecause I would conditionally vacate the judg men t and remand with instructions t o t h e district court to conduct a Daubert determination in the first instance, I r espectfully dissent from Parts I I and I I I of the majority opinion.

I.

A district court must “ensure the reliability and relevancy

o f e x pert testimony ” and “ make certain that an ex pert, whether basing testimony upon professional studies o r personal ex perience, employ s in the courtroom the same level of intellectual rig or that characteriz es the practice of an ex pert in the relevant field. ” K

u m h o Tire Co., Ltd. v. Carmichael
, 526 U.S. 137, 152 (1999); see also F ed. R. E v i d. 702. I n short, a district c ourt serves an essential “g atekeeping ” function in evaluating proffered ex pert testim o n y

. Kumho Tire , 526 U.S. at 141.

I n this c ase, the d istrict c o urt abdicated its g atekeeping role by failing to evaluate the relevancy and reliability of the

ex p ert testimony at issue. Given this oversig ht, w e m u st determine whether the d istrict court’s misstep resulted in the admission of evidence that should h ave been ex cluded. I n theE S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 22

past, w hen the record before u s was s u f f i c i e n t to make this determination, we have proceeded to evaluate whether the

erroneous admission or ex c lusion of e vidence was harmless. See, e.g. , United States v. Morales
, 720 F .3d 1194, 1 197 (9th Cir. 2013) (district court’s error “was harmless because t he erroneously admitted h earsay did not materially affe c t the verdict”); United States v

. 4.85 Acres of Land
, 546 F

. 3d 613, 620 (9th Cir. 2 008) ( district court’s erro r w a s not harmless because improper ex clusion o f evidence was prejudicial). This approach makes perfect sense—once we d etermine that in a d m i ssible e vidence w as presented, or that admissible

e v i d e nce was ex cluded, we can then a naly z e whether t h e

error materially affected the verdict. See United S tates v

. Bailey , 696 F .3d 794, 803 (9th Cir. 2012).

Here, however, we f

ace a markedly different scenario. A s the majority correctly concludes, “the admissibi lity of the

ex p ert testimony at issue” c annot be determined “because the record before u s is too sparse.” Maj. Op. at 19. Giv e n t h i s conclusion, harmless e rror r eview is si m ply not possible at the current juncture. I ndeed, we cannot e v e n say whether there was an “error” to “materially affect the verdict.” I f the disputed ex pert testimony was a dmissible p ursuant to Rule 702 and Daubert
, despite the district court’s failure to fulfill its g atekeeping function, then n o harm, no foul. On the other hand, if the testimony was inadmissible, then a harmless error analy sis would be appropriate. Thus, in lig ht of the outstanding question reg arding the admissibility of the ex pert testimony at i s s u e, a remand to the district court for a Daubert analy sis is the proper course.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 23

II.

The majority g oes awry in adopting an approach that ig nores this antecedent question of admissibility

. I n considering the d istrict c o u rt’s g a tekeeping failure, the majority asserts that “[ w] hen we conclude evidence has been improperly admitted, ‘we consider whe t h e r the error was harmle s s

. ’ ” Maj. Op. at 13 (quoting Bailey
, 696 F .3d at 802–03). Thoug h innocuous at first g lance, thi s remark ha rb o r s a g rave oversig ht: it equates an incorrect determination of admissibility with a failure t o c o n d uct a Daubert analy sis.

The disti n c t ion between the two is crucial. W ith the former, we know w hether a p a r t y was wrong fully p ermitted

or denied the opportunity to present certain evidence, and we

can determine whether that error w as prejudicial

. W i t h the latter, we cannot g aug e prejudice unless we are a ble to determine what the jury would have bee n p er m i tted to hear had the district court properly discha r g ed its g atekeeping duties. 1

B y skipping over the question o f admissibility a nd heading straig ht for prejudice, the majority ’s analy sis r esults in two key missteps. F irst, the majority dubs the B arabins “the b eneficiaries of

. . . erroneously admitted evidence.” Id.

1 T h e m aj o rity cites Un ited Sta tes v. Ra h m , 9 9 3 F.2 d 1 4 0 5 (9 th Cir. 1 9 9 3 ), f o r th e p ro p o sitio n th a t “ [w ]e treat th e erro n eo u s ad m issio n of

ex p ert testim o n y th e sam e as all o th er ev id en tiary erro rs, b y s u b j ectin g i t to h arm less erro r rev iew .” Maj

. Op

. at 1 3

. Ra h m , h o w ev er, o n ly en g ag ed in h arm less erro r rev iew after co n clu d i n g th at th e testim o n y at issu e w as

a d m i s s ib le an d th u s im

p ro perly ex clu d ed

. S

ee Ra h m , 9 9 3 F.2 d at 1 4 1 6 (d eem in g th e erro r n o t h arm less w h ere th e d istrict co u rt “ erro n eo u sly

ex clu d ed . . . p ro f

f ered ex p ert testim on y

. . . [th at] w as ad m issib le”).E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 24

a t 14. B ut, a s the majority acknowledg es, we have no ide a whether the ex p ert testimony at issue was in fact “erroneously admitted.” On a proper Daubert analy sis—a task we decline
t o eng ag e in on appeal—the testimony mig ht indeed h a v e been admissible. I n this c ircumstance, the B arabins would merely b e the beneficiaries of evidence they were entitled to present in the first place.

Second, in by

passing admissibility
, the majority eng ag e s in a perpl e x i n g prejudice analy sis that emphasiz es the fact th a t t h e d isputed ex pert testimony was “critical to the proponent’s case.” 2 Id

. I ndeed, based on its conclusion that “the B arabins’ claim depended wholly upon the erroneously admitted evidence,” the majority finds “no d o ubt the error was not harmless.” I

d

. N ot so. Even if the B arabins’ claim depended on the ex pert testimony at issue, w e h a ve n o idea whether the testimony was “erroneously admitted,” let alone whether any error “materially affect[ ed] t h e v erdict.” Morales
, 7 20 F .3d at 1197. I f the e x pert t estimony was admissible, then the jury simply reache d a v e rdict based on evidence it w as properly p ermitted t o c o n s ider, despite the district court’s error.

The flaw in the majority ’ s log ic is hig hlig h ted by the fact that n ot a s i n gl e c a s e it cites supports the ty pe of harmless

error a naly sis it applies. Rather, in each case, we eng ag e d in harmless e rror review only after w e determined that evidence

2 It seem s to m e t h at it w o u ld b e th e rare case in d eed w h ere ex p ert testim o n y w as n o t “ critical to th e p ro p o n en t’ s case.”E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 25

had been improperly d e em e d admissible or inadmissible. 3 I ndeed, this is true of Simpson v. T h o m as and United States

v. 4.85 Acres o

f Land —two cases specifically discussed b y the majority in support o f i ts decision. Contrary to the majority ’s assertion, neither case involved merely a situation where a “district court a

bdicate[ d] its responsibility to answer

a t h r e s h o ld question of admissibility .” Maj. Op. at 16. Rather, in both cases, we found actual err o r b y t he d istrict
court in deeming evidence admissible o r inadmissible before proceeding to harmless error review. See Simpson
, 528 F .3d
at 689 ( “The district c ourt erred in admitting the evidence o f Simpson’s three prior felony convictions.”); 4

. 85 Acres of Land
, 546 F .3d at 620 (“[ T] he [ d istrict] court simply

ex c luded all post-taking sales based on ‘the erroneous premise

. . . that e vidence of subsequent sales is never proper for c onsideration in arrivin g at fair market v a lue.’” (quoting

3 S ee, e.g

. , Ba i ley
, 6 9 6 F .3 d at 8 0 5 (n o t h arm less erro r w h ere t rial co u rt

w ro n g f u lly ad m itted a civ i l co m

p lain t ); Ju les Jo rd

a n Vi d eo , In c. v. 1 4 4 9 4 2 Ca n ad a, In c ., 6 17 F

. 3 d 1 1 4 6
, 1 1 58 –5 9 (9 th C ir. 2 0 1 0 ) (h arm less erro r

w h ere district co u rt im

pro p erly p erm i tted co u n sel to read 7 1 6 req u ests f or ad m i ssio n s to th e j u ry ); Un ited S ta tes v. La u rien t i
, 6 1 1 F.3 d 5 30
, 5 4 8 (9 th Cir. 20 1 0 ) (h arm less erro r w h ere d istrict co u rt ab u sed its d iscretio n b y

su stain i n g certai n g ov ern m en t o b j ectio n s to ex pert t estim o n y ); S imp so n

v. Th o ma s , 5 2 8 F.3 d 6 8 5
, 69 1 (9 th Cir. 2 0 0 8 ) (n o t h arm less erro r w h ere d istrict co u rt im

pro perly ad m itted prio r co n v ictio n s); 4 .8 5 Acres o f La n d
, 5 4 6 F

. 3 d at 62 0 (n o t h arm l ess erro r w h ere d istrict co u rt im

p ro p erly

ex clu d ed p o st- t ak in g sales in a co n d em n atio n actio n ); Co h en , 51 0 F.3 d at 1 1 2 7 (n o t h arm less erro r w h ere d istrict co u rt w

ro n g f u l ly ex clu d ed ex p ert testim o n y ); Ob rey v. J

o h n s o n , 4 0 0 F.3 d 6 9 1
, 70 2 (9 th Cir. 2 0 0 5 ) (n o t h arm less erro r w

h ere d istrict co u rt ab u sed i ts d iscreti o n i n e x clu d in g testim o n y ) ; Ra h m , 9 9 3 F.2 d at 1 4 1 5 (n o t h arm less erro r w h ere d istrict

co u rt erro n eo u sly ex cl u ded ex p ert testim o n

y ); Un ited S ta tes v. Ech a va r ria -Ola rte , 9 04 F .2 d 1 39 1
, 1 3 9 8– 9 9 (9 th Cir. 1 9 9 0 ) (h arm less

erro r w h ere d istr i ct co u rt im

p ro perly ad m itted ex

p ert testim o n y o n d ru g cartel).E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 26

U n i t ed S tates v. 1,129.75 A c res of Land
, 473 F .2d 996, 99 9 (8th Cir. 1973)) (final alteration in orig inal)).

I n fact, our case law sug g ests a notably different harmless

error inquiry when a district court fails to fulfill i ts g atekee p ing f

unction. F or e x ample, in Hangarter v

. Provident Life & Accident Insurance Co. , 373 F .3d 998 (9th Cir. 2004), the district co u r t incorrectly concluded that Daubert was i n a p plicable to the non-scientific testimony o f

an independent consultant. Id. at 1015–16, 1018. W e f ound the error h armless because “the [ district] court’ s probing o f [ the consultant’s] knowledg e and ex perience wa s sufficient
to satisfy its g a tekeeping role under Daubert .” Id. at 1018. I n short, the d istrict court’s f ailure to analy

z e the ex pert testimony pursuant t o D aubert was harmless because the analy sis it nonetheless conducted satisfied Daubert and the testimony was thus c orrectly admitte d

. T h i s was a proper application of h a

r mless error r eview—where the error identified on appeal pertains to the g atekeeping function, the reviewing c ourt should consider whether the gat e k eeping

error was harmless. 4

I n c ontrast, the majority here finds a g a t ekeeping error, but embarks on a p r ejudice i n q u i r y that focuses on h ow crucial the disputed ex p e r t testimony was to the prevailing
p a r ty ’s success. I n doing so, the majority effectively treats the testimony as inadmissible
, even a s it professes to reserve

4 T h e m aj o rity ch aracterizes Ha n g a rter as “ in ap p o site,” describ in g it as

a case w h ere th e d ist r i c t c o u rt “ d id n o t f ail to f u lf ill its g atek eep in g f u n ctio n .” Maj

. Op

. at 1 6 n .7

. I d isag ree. It is h ard to i m a g i ne a m ore clear g atek eep in g erro r th an a d istrict co u rt ch o o sin g n o t to a n aly ze p ro f f ered ex p ert testim o ny u n d er Da u b ert b ecau se it m istak en l y f o u n d Da u b ert in ap plicab l e.E S T A T E O F B A R A B I N V

. A S T E

N J O H N S O N 27

judg ment on the question. The majority cannot have it both
way s.

III.

I would conditionally vacate the judg ment and remand to the district cou r t w i th instructions to determine whether the disput e d e x pert testimony w as admissible pursuant to the requirements of Rule 702 and Daubert

. I f the testimony is d etermined to be admissible, the d istrict court may rein s t a t e the verdict. I f, however, the testimony is inadm i s s i b le, the district court should ascertain w hethe r the wrong f ul admission of that ex pert testimony prejudiced the defendants and, if so, order a new trial. I n the former c a s e , the sy stem will n o t b e u n r easonably b urdened with a retrial. I n either
case, the parties retain the i r rig h t to appeal. This solution makes practical and leg al sense.