                                                                              F I L E D
                                                                       United States Court of Appeals
                                                                               Tenth Circuit
                    UNITED STATES COURT OF APPEALS
                                                                                SEP 19 1997
                                  TENTH CIRCUIT
                                                                          PATRICK FISHER
                                                                                    Clerk


 GREG WALLIS, Parent of Skylar
 Wallis, deceased, SHERRI WALLIS,
 Parent of Skylar Wallis, deceased, and
 BETTY WALLIS, Individually,
                                                       No. 95-7176, 96-7002
               Plaintiffs - Appellants,              (D. Ct. Nos. CIV-94-676 &
                                                           CIV-94-676-B)
          v.                                                 (E.D. Okla.)

 CARCO CARRIAGE
 CORPORATION, INC., d/b/a Hertz
 Rent-A-Car Licensee and CAMPBELL
 HARDAGE, INC., a Corporation,

               Defendants - Appellees/
               Cross-Appellants,

          v.

 WANDA A. NASH, Executrix of the
 Estate of Neil G. Nash, deceased,

               Third-Party Defendant.




                            ORDER AND JUDGMENT *




      *
        This order and judgment is not binding precedent, except under the doctrines of
law of the case, res judicata, and collateral estoppel. This court generally disfavors the
citation of orders and judgments; nevertheless, an order and judgment may be cited under
the terms and conditions of 10th Cir. R. 36.3.
Before TACHA, LUCERO, and DANIEL, ** Circuit Judges.


      Plaintiffs Betty Wallis, Scott Wallis, and Sherri Wallis appeal a jury verdict

in their favor against defendant Carco Carriage Corporation (“Carco”). At trial,

the plaintiffs alleged that Carco, a car rental company, negligently entrusted a

vehicle to an intoxicated driver, Neil Nash, who injured Betty Wallis and killed

Skylar Wallis in an automobile accident. The jury awarded Betty Wallis

$142,708.23 as compensation for her injuries and awarded Scott and Sherri Wallis

$36,274.13 as compensation for the death of their son, Skylar.

      The plaintiffs appeal the jury verdict on two grounds. First, the plaintiffs

argue that the district court abused its discretion in refusing to grant them a new

trial because the damage award was inadequate. Second, the plaintiffs assert that

the district court committed reversible error in permitting Carco to suggest that

Nash and his employer, Campbell Hardage, Inc., had settled with the plaintiffs.

      Carco cross-appeals on two grounds. First, Carco contends that the district

court abused its discretion in permitting the plaintiffs to offer retrograde

extrapolation evidence to determine Nash’s blood alcohol content at the time of

the rental transaction. Second, Carco argues that the district court erred in

refusing to grant a directed verdict for Carco based on the absence of any



       The Honorable Wiley Y. Daniel, United States District Judge for the District of
      **

Colorado, sitting by designation.

                                           2
evidence establishing that Carco knew or should have known of the driver’s

intoxicated state at the time of the rental transaction. We have jurisdiction

pursuant to 28 U.S.C. § 1291 and affirm.



                                   BACKGROUND

      In the early morning of September 10, 1995, Neil Nash left his motel in

Richmond, Indiana, and drove to the airport in Dayton, Ohio. He took a 6:00 am

flight from Dayton to Dallas, Texas. From Dallas, Nash caught a 10:00 am flight

to Fort Smith, Arkansas. At 10:56 am, Nash rented a car from Carco to drive to

nearby Poteau, Oklahoma, for business purposes. Between 11:30 and 11:45 am,

as Nash was driving his rental car, he crossed the center line and collided with

another vehicle. Betty Wallis, the driver, suffered physical injuries. Skylar

Wallis, her grandson, died in the collision.

      Shortly after the accident, Nash received two intravenous fluid infusions.

At about 1:00 pm, the authorities drew a sample of Nash’s blood. Subsequent

tests performed by the Oklahoma State Bureau of Investigation revealed that

Nash’s blood alcohol content (“BAC”) was 0.32% to 0.36%. 1



      1
          The laboratory test results revealed a BAC of 0.26%. Nash’s blood, however,
was lowered by his blood loss and the administration of various fluids during his medical
treatment after the accident. Based on the emergency medical and hospital records, the
plaintiffs’ expert estimated that Nash’s true BAC was between 0.32% and 0.36%.

                                            3
      On December 30, 1994, Betty, Greg, and Sherri Wallis brought a personal

injury action against Carco, alleging that Carco negligently entrusted the vehicle

to Nash while he was intoxicated. The plaintiffs also sued Nash and his

employer, Campbell Hardage, Inc.

      On August 7, 1995, the parties selected a jury. The district court, however,

postponed the trial for two weeks. Between the time of the jury selection and

opening statements, the plaintiffs settled with Nash and Campbell Hardage for

$1,850,000. The plaintiffs proceeded to trial against only Carco.

      At trial, the plaintiffs’ expert, Dr. Kurt Dubrowski, testified about the

effects of alcohol and the rate of metabolization in individuals with a physical

condition similar to that of Nash. Assuming that Nash’s BAC was 0.36% at the

time of the accident, Dr. Dubrowski estimated what Nash’s BAC would have been

during the rental transaction. He emphasized that his calculations varied based on

Nash’s alcohol consumption after the rental transaction, as well as Nash’s

drinking habits, stress levels, fatigue, and other factors.

      At trial, Carco sought to introduce evidence of the plaintiffs’ settlement

with Campbell Hardage and Neil Nash. Over Carco’s objections, the district

court refused to admit any evidence regarding the settlement agreement. Instead,

the court instructed the jury that Campbell Hardage was no longer a party to the

suit and not to consider why Campbell Hardage was no longer a party. The court,


                                           4
however, permitted Carco to ask the plaintiffs whether they had filed a lawsuit

against Neil Nash and Campbell Hardage.

      At the close of the plaintiffs’ case, Carco moved for judgment as a matter

of law pursuant to Federal Rule of Civil Procedure 50(a), arguing that the

evidence was insufficient to show that Carco knew that Neil Nash was

intoxicated. The court denied the motion.

      On August 28, 1995, the jury returned a verdict in favor of Greg and Sherri

Wallis in the amount of $36,274.13 and in favor of Betty Wallis in the amount of

$142,708.23. The district court offset the entire amount because the verdict was

less than the $1,850,000 settlement. See Okla. Stat. Ann. tit. 12, § 832(H).

      The plaintiffs moved for a new trial pursuant to Federal Rule of Civil

Procedure 59(a), arguing that damages were inadequate and unreasonably low.

Carco renewed its Rule 50 motion for judgment notwithstanding a verdict based

on the absence of any evidence that Carco knew that Neil Nash was intoxicated.

The district court denied both post-trial motions. This appeal followed.



                                  DISCUSSION

I.    A DEQUACY OF THE J URY V ERDICT

      The plaintiffs argue that district court abused its discretion in refusing to

grant them a new trial because the jury’s verdict awarding $35,273.53 to Greg and


                                          5
Sherri Wallis and awarding $142,708.23 to Betty Wallis was inadequate. We

review the district court’s determination that the damages awarded by the jury

were not so inadequate as to require a new trial for an abuse of discretion. Mason

v. Oklahoma Turnpike Auth., 115 F.3d 1442, 1457 (10th Cir. 1997). We will find

no abuse of discretion unless the verdict is so inadequate “as to shock the judicial

conscience and to raise an irresistible inference that passion, prejudice,

corruption, or other improper cause invaded the trial.” Bennett v. Longacre, 774

F.2d 1024, 1028 (10th Cir. 1985) (quoting Barnes v. Smith, 305 F.2d 226, 228

(10th Cir. 1962)).

      A.     Verdict in Favor of Greg and Sherri Wallis

      Greg and Sherri Wallis argue that the district court abused its discretion in

refusing to grant them a new trial on the ground that the jury award of $35,273.53

was inadequate. In particular, Greg and Sherri Wallis assert that because they

sought to recover $33,356.45 in medical expenses and $2,917.08 in funeral

expenses, the $35,273.53 jury award only compensated them for medical and

funeral expenses. Greg and Sherri Wallis maintain that the jury ignored “clear,

substantial, and totally unrefuted evidence of a close, constant, and loving

relationship” between the plaintiffs and their son. App’t Brief, at 4.

      “In diversity cases involving damages, the federal court must look to

appropriate state law to ascertain the elements of the allowable damages.” Black


                                          6
v. Hieb's Enters., Inc., 805 F.2d 360, 365 (10th Cir. 1986). Under Oklahoma law,

parents may recover damages for the death of a minor child. The relevant statute

states:

          In all actions hereinafter brought to recover damages for the death of
          an unmarried, unemancipated minor child, the damages recoverable
          shall include medical and burial expense, loss of anticipated services
          and support, loss of companionship and love of the child, destruction
          of parent-child relationship and loss of monies expended by parents or
          guardian in support, maintenance and education of such minor child,
          in such amount as, under all circumstances of the case, may be just.

Okla. Stat. Ann. tit. 12 § 1055.

          The Supreme Court of Oklahoma recently addressed the scope of

section 1055 in Death of Lofton v. Green, 905 P.2d 790 (Okla. 1995). In

that case, a mother’s six-year-old child drowned in a neighbor’s swimming

pool. Id. at 791. The mother brought a wrongful death suit alleging that the

pool was an attractive nuisance. Id. The jury awarded the mother $4,200 in

damages, and the mother appealed, arguing that the jury verdict was

inadequate. Id. Affirming the award, the court stated:

                 We are mindful of the loss this parent has suffered. It is the
          function of the jury however, to properly evaluate the various
          elements of alleged damages and to pass upon the credibility of lay
          witnesses and determine the weight and value of their testimony.
          The extent of the plaintiff's pecuniary and emotional loss was a
          matter exclusively for the jury to determine. Evidence must be
          introduced to support an award. In that Appellants do not direct us
          to any evidence which would substantiate a reversal, the damage
          award is sustained.


                                             7
Id. at 793 (citations omitted). Lofton makes clear that while section 1055

permits a jury to award damages for loss of companionship and destruction

of the parent-child relationship, the statute does not require the jury to make

such an award in every case.

      After carefully reviewing the record on appeal, we conclude that the

district court did not abuse its discretion in refusing to grant a new trial

based on an inadequate damage award. At trial, Greg and Sherri Wallis

testified that they had maintained a good relationship with their son. Their

testimony, however, also established that they were divorced, and as a result,

Skylar spent much time with his grandmother. Under these circumstances,

“[t]he jury was entitled to disbelieve their testimony or to give it as much

weight as it felt it deserved.” Crane v. Mekelburg, 728 F.2d 439, 443 (10th

Cir. 1984). “Damages are not grossly inadequate merely because a jury

awards less than the plaintiff has requested. ‘The jury is entitled to disregard

the damages asked for if they do not agree with the computations or if other

evidence is introduced from which jurors could draw their own

conclusions.’” Shugart v. Central Rural Elec. Coop., 110 F.3d 1501, 1506

(10th Cir. 1997) (quoting Luria Bros. & Co. v. Pielet Bros. Scrap Iron &

Metal, Inc., 600 F.2d 103, 115 (7th Cir. 1979)).




                                         8
      We recognize that Skylar’s death is tragic. “Even though this court

might have awarded damages on a different plane, this is not the test as to

whether the jury's verdict was in error.” Crane, 728 F.2d at 443. Instead, we

must determine whether the verdict “shocks the judicial conscience” such

that we may infer that “passion, prejudice, corruption, or other improper

cause invaded the trial.” Bennett, 774 F.2d at 1028. After reviewing, the

record, we cannot infer that bias and prejudice was present in this case.

      B.     Verdict in Favor of Betty Wallis

      Betty Wallis argues that the district court abused its discretion in

refusing to grant her a new trial because the jury awarded her only

$143,708.23 in damages. Betty Wallis emphasizes that she sought to recover

$118,708.23 in medical expenses and $14,725.00 in lost wages. Thus, she

contends that the verdict of $143,708.23 constituted $118,708.23 for medical

expenses, $14,725.00 for lost wages, and $10,275.00 for her pain and

suffering, disability, emotional distress, and other injuries. Betty Wallis

asserts that the $10,275.00 was inadequate to compensate such injuries.

      After carefully reviewing the record on appeal, we conclude that the

district court did not abuse its discretion in refusing to grant a new trial

based on an inadequate damage award. In short, Betty Wallis has not shown

that the award of $10,275.00 for pain and suffering “shocks the judicial


                                        9
conscience” and fails to point to any evidence indicating passion or prejudice

on the jury’s part. See Black, 805 F.2d at 362. Although the evidence of

Betty Wallis’s damages was not directly controverted, it is quite possible

that the jury did not find her experts to be convincing. See Moore v. Subaru

of America, 891 F.2d 1445, 1452 (10th Cir. 1989). “This was properly

within the jury’s province.” Id. We refuse to alter a jury verdict without

further proof of jury passion or prejudice. Thus, we affirm the district

court’s denial of a new trial based on the inadequacy of damages.

II.   E VIDENCE OF THE S ETTLEMENT A GREEMENT

      The plaintiffs contend that the district court erred in permitting Carco

to “suggest” that the plaintiffs had settled with Nash and Campbell Hardage.

In response, Carco asserts that the district court erred in failing to admit

evidence of the settlement agreement to prove bias or prejudice of a witness.

      We review the district court’s admission or exclusion of evidence

under an abuse of discretion standard. United States v. Davis, 40 F.3d 1069,

1073 (10th Cir. 1994). “Under the abuse of discretion standard, a trial

court’s decision will not be disturbed unless the appellate court has a

definite and firm conviction that the lower court made a clear error of

judgment or exceeded the bounds of permissible choice in the

circumstances.” Boughton v. Cotter Corp., 65 F.3d 823, 832 (10th Cir.


                                       10
1995) (quoting McEwen v. City of Norman, 926 F.2d 1539, 1553 (10th Cir.

1991)).

      A.     Admission of Evidence “Suggesting” Settlement

       On appeal, the plaintiffs argue that the district court abused its

discretion in permitting Carco to “suggest” that the plaintiffs had settled

with Campbell Hardage. The plaintiffs assert that the settlement evidence

was irrelevant to the only issue in the case—whether Carco knew or should

have known that Neil Nash was intoxicated during the rental transaction and

the amount of damages—and, therefore, such evidence was unduly

prejudicial. See Fed. R. Evid. 401, 402, & 403.

      The plaintiffs contend that four times during the trial, Carco implied

that they had settled with Nash and Campbell Hardage. The first incident

involved Carco’s cross-examination of Eric Nickell, a witness to the

accident:

      Q:     Did you ever go to the car where the other people were hurt?
      A:     Yes.
      Q:     But your wife attended to Mr. Nash, the driver of the --
             responsible party?
      A:     Yes.
      Q:     And you said that you smelled alcohol on Mr. Nash, the driver
             of the responsible car?
      A:     Right.

App’t App. at 119. The second incident involved Carco’s cross-examination

of Greg Wallis:

                                       11
      Q:     When you filed this lawsuit, you also sued Campbell Hardage,
             Inc., a corporation, did you not?
      A:     Yes.
      Q:     And you filed suit against them for the acts of their employee,
             Neil Nash?
      A:     And I also -- yes.

App’t. App. at 132. The third incident occurred when Carco’s attorney

cross-examined Sherri Wallis:

      Q:     Ma’am, when this suit was filed you filed suit against
             Campbell Hardage, did you not?
      A:     Yes, sir.
      Q:;    And you were blaming them for causing this accident?
      A:     Yes, sir.
      Q:     And, in fact, until a week ago this Friday they were still a
             party to this lawsuit, were they not?
      A:     Yes, sir.

App’t App. at 164. The final incident occurred during closing arguments.

The following exchange took place between the defendant’s counsel (D), the

plaintiffs’ counsel (P), and the court (C):

      D:     Now, the fact of the matter is in the entire presentation of this
             case through the testimony, and you have common sense, that
             plaintiff, Mr. George and the attorney for Campbell Hardage
             had one purpose in mind together. They had a common
             understanding to put the blame on Carco. You could tell by
             the questions they were asking. They both tried to put the
             blame on Carco. They were in bed together.
      P:     Your Honor, that’s highly improper.
      C:     It will be overruled.
      D:     They were in bed together. He then gets out of bed and tries to
             put us in bed with Campbell Hardage. That’s what they were
             doing and then a week ago, last Friday, Campbell Hardage is
             no longer here. But they want you and they ask you — they
             look you straight in the eye and say, ‘We want Carco to pay for

                                          12
             this, to pay all of our damages.’ Now, I ask you, who is being
             fair and up front in this case? Now, you will remember Mr.
             Hamilton, the stock car racer. He tells us when everybody is
             in this lawsuit that there is a pint or half a pint out there half
             full and that he associated that liquor with Mr. Neil Nash.
             Then he comes in here and suddenly he doesn’t associate it.
             Now the parties in bed together are different.
      P:     Your, Honor, that isn’t the evidence.
      D:     He said that in his deposition.
      C:     Well, the jury will have to recall what the evidence was.
             Arguments of counsel are not evidence, as I have told you.
             Please proceed.
      D:     You will remember the evidence. At the time of the accident
             he associated it with the accident, but when he testified he did
             not.

App’t App. at 165.

      Although the above-quoted testimony was not relevant to the central

issue in the case, we hold that the district court did not abuse its discretion

in permitting Carco to question the witnesses about the liability of Nash and

Campbell Hardage. As the district judge concluded, Carco was entitled to

argue that Nash and Campbell Hardage were the sole proximate cause of the

accident:

      This is not any different than any other case. I mean, [Carco’s]
      defense is that [it] did not do anything and that somebody else caused
      the accident, so to speak.

App’t App. at 127. Moreover, the district court recognized that the jury

knew that the plaintiffs had filed suit against Nash and Campbell Hardage:

      [The] jury already knows there was a claim against Campbell
      Hardage. When this case started out they knew it. They heard voir

                                           13
      dire questions about it. They know that the claim was made and I
      don’t see how there is — you know, there is nothing that I can do or
      say to erase that.

App’t App. at 124-25. We conclude that the district court did not abuse its

discretion in permitting Carco to conduct a limited inquiry into the liability

of the settling defendants and the plaintiffs’ lawsuit against them.

      B.     Admissibility of the Settlement Agreement

      Carco contends that the district court abused its discretion in refusing

to admit evidence of the settlement agreement between the plaintiffs,

Campbell Hardage, and Nash. Under Federal Rule of Evidence 408,

settlement agreements are “not admissible to prove liability” but may be

admissible if “offered for another purpose, such as proving bias or

prejudice.” Fed. R. Evid. 408. Carco asserts that the district court abused

its discretion in excluding evidence of the settlement agreement to show bias

under Rule 408. Carco, however, fails to explain how it would have

impeached any witness with the settlement agreement. Moreover, Carco

fails to recognize that Rule 408 is merely an exclusionary rule, not one

providing for the admission of evidence. Thus, even if Carco sought to show

bias or prejudice of a witness in introducing the settlement agreement, the

district court may still exclude the evidence under Federal Rule of Evidence

403 if the danger of unfair prejudice substantially outweighs the relevance of


                                       14
the evidence. See Weir v. Federal Ins. Co., 811 F.2d 1387, 1395 (10th Cir.

1987). As we explained in Weir:

      The prejudicial effect of allowing a jury to hear of the circumstances
      surrounding the settlement of a claim was one of the concerns that
      motivated the drafters of the Federal Rules of Evidence to absolutely
      prohibit the use of evidence of a settlement to prove liability or the
      amount of a claim. Fed. R. Evid. 408. Although Rule 408 does not
      prohibit the admission of evidence of the circumstances surrounding
      a settlement to prove something other than liability—such as
      voluntariness—many of the same concerns about prejudice and
      deterrence to settlements exist regardless of the purpose for which
      the evidence is offered.

Id.

      In this case, the district court was clearly concerned that admission of

the settlement agreement would prejudice the plaintiffs. The court, however,

permitted the defendants to conduct a limited inquiry into the plaintiffs’

lawsuit against the settling defendants. Under these circumstances, we

conclude that the district court did not abuse its discretion in declining to

admit the settlement agreement itself.

      Alternatively, Carco asserts that the settlement is admissible under the

holding of Warner/Elektra/Atlantic Corp. v. County of DuPage, No. 83-C-

8230, 1991 WL 32776 (N.D. Ill. Mar. 6, 1991). Carco asserts that the

settlement agreement is admissible to prove that the conduct of Nash—and

not Carco—was the sole proximate cause of the plaintiffs’ injury.



                                         15
      In County of DuPage, the plaintiffs sued several defendants as a result

of the flooding of a warehouse. Id. at *1. The sole nonsettling defendant

sought to prove that the settling defendants were the sole proximate cause of

the accident. Id. In admitting such evidence, the court stated that “plaintiffs

would have the issue of proximate cause tried in a vacuum, with no reference

to the other actors whose conduct may also have been a proximate cause of

plaintiffs’ injury.” Id. at *3. Without such evidence, the court reasoned,

“the jury’s natural question—‘If not you, who?’—would be left

unanswered.” Id.

      County of DuPage is clearly distinguishable from the present case. In

short, County of DuPage addressed only the admissibility of the negligence

of a settling tortfeasor, not the admissibility of a settlement agreement. The

language of Rule 408 is clear: settlement agreements are not admissible to

prove liability. Thus, the district court did not abuse its discretion in

refusing to admit evidence of the settlement agreement to prove the liability

of the settling defendants. 2


      2
          Carco also asserts that evidence of the settlement agreement is admissible
because “Oklahoma law allows for admission of evidence of out of court settlements by
co-defendants.” App’t Brief, at 23. Though not entirely clear from the briefs, Carco
apparently contends that Rule 408 conflicts with Oklahoma’s substantive law on the
admissibility of settlement agreements. See Carota v. Johns Manville Corp., 893 F.2d
448, 451 (1st Cir. 1990) (“If a state has a substantive policy to have a jury hear out of
court settlement evidence when determining damage awards, we will not contravene that

                                         16
III.   R ETROGRADE E XTRAPOLATION E VIDENCE

       Carco argues that the district court erred in admitting the testimony of

Dr. Kurt Dubrowski regarding retrograde extrapolation evidence.

Retrograde extrapolation is a method of estimating a person’s blood alcohol

level at a specified time by using the person’s known blood alcohol content

at a later time. Carco asserts that because the amount of alcohol that Nash

consumed after the rental transaction was unknown, retrograde extrapolation

is unreliable and speculative. We review the district court’s admission of the

retrograde extrapolation evidence in this case for an abuse of discretion.

United States v. Wilson, 107 F.3d 774, 782 (10th Cir. 1997).

       At trial, Dr. Dubrowski prepared a chart that calculated what Nash’s

blood alcohol content would have been depending on how much he drank in

the 35 to 45 minute interval between the rental transaction and the accident.

For example, if Nash had not consumed any alcohol during that interval, he

would have had a BAC of 0.39% at the time of the transaction. Similarly, if




state law in a diversity action.”).
        We have reviewed Oklahoma’s law on the admissibility of settlement agreements.
Oklahoma’s evidentiary rule on settlement agreements closely resembles Rule 408. See
Okla. Stat. Ann. tit., 12 § 2408. Moreover, unlike Carota, Oklahoma has no substantive
law requiring the jury to reduce a jury verdict by the compensation already received by
the plaintiff from absent settling tortfeasors. See Cleere v. United Parcel Serv., Inc., 669
P.2d 785, 789 (Okla. Ct. App. 1983). Thus, we reject Carco’s argument that the
settlement agreements in this case were somehow admissible under Oklahoma law.

                                          17
Nash had consumed twelve ounces of 90-proof whiskey, his BAC would

have been 0.15% at the time of the rental transaction. In addition to

emphasizing that his calculations varied based on Nash’s alcohol

consumption after the rental transaction, Dr. Dubrowski informed the jury

that his findings depended on Nash’s drinking habits, stress levels, fatigue,

and other factors.

      We hold that the district court did not abuse its discretion in admitting

Dr. Dubrowski’s retrograde extrapolation testimony. Dr. Dubrowski did not

give a definitive estimate of Nash’s BAC at the time of the rental

transaction. Instead, the expert testified that his determination of Nash’s

BAC at the time of the rental transaction depended on Nash’s consumption

of alcohol during the 35 to 45 minute time interval between the transaction

and the accident. Carco’s objections to the speculative nature of such

testimony go to the weight, and not the admissibility, of the evidence.

      Carco’s reliance on United States v. DuBois, 645 F.2d 642 (8th Cir.

1981) is misplaced. In DuBois, the Eighth Circuit addressed the

admissibility of retrograde extrapolation evidence in a drunk driving case.

Id. at 643. The evidence indicated that the defendant drank one beer before

getting into his car. Id. As he was driving, the defendant struck and killed a

pedestrian. Id. Instead of remaining at the scene of the accident, the


                                       18
defendant proceeded to a nearby town and purchased a six-pack or twelve-

pack of beer. Id. The defendants’ children observed the defendant drink

two to four cans of beer after the accident. Id. Another witness testified

that the defendant drank one can of beer. Id. A breathalyser test

administered less than three hours after the accident revealed that the

defendant had a BAC of 0.22%. Id.

      At trial, a forensic chemist attempted to estimate the defendant’s BAC

at the time of the accident. Id. The chemist assumed that the defendant had

“an average” of three beers after the accident. Id. Based on a “burn off”

rate of 0.15 percent per hour, the chemist estimated that the defendants BAC

was 0.22% at the time of the accident. Id.

      On appeal, the Eighth Circuit concluded that the evidence was

insufficient to prove beyond a reasonable doubt that the defendant was

driving while intoxicated. The court reasoned:

      While there may be instances where an expert’s estimate could
      account for intervening consumption and could thus serve as
      sufficient evidence of intoxication at the earlier time, this is not such
      a case. When there has been intervening consumption an accurate
      estimate requires knowledge of three variables: the blood alcohol
      level at the later time, the time elapsed since the accident, and the
      amount consumed in the interim. In this case, the expert did not
      know the amount consumed in the interim. Possibilities ranged
      anywhere from three to twelve beers. As a result, Ms. Pearson's
      conclusion that the defendant had a .22 or even a .1 per cent blood
      alcohol at the time of the accident is simply conjecture, and it is well


                                          19
      established that “a jury is not justified in convicting a defendant on
      the basis of mere suspicion, speculation or conjecture.”

Id. at 644-45 (citations omitted).

      We agree with the DuBois court’s observation that there may be

inherent difficulties in making a retrograde extrapolation calculation when

there is an intervening consumption of alcohol. Nevertheless, DuBois is

distinguishable from the present case on several grounds. First, DuBois

involved a sufficiency of the evidence issue, while the present case involves

the admissibility of evidence. Second, DuBois was a criminal case, not a

negligence action. Third, the expert in DuBois calculated the defendants

BAC based on an “average” intervening consumption of three beers. In

contrast, Dr. Dubrowski estimated Nash’s BAC at the time of the rental

transaction depending on Nash’s alcohol consumption between the

transaction and the accident. Finally, in DuBois, the evidence indicated that

the defendant had consumed alcohol during a three-hour period between the

accident and the defendant’s arrest. In this case, the record indicates that the

interval between the rental transaction and the accident was only thirty-five

to forty-five minutes. Accordingly, we hold that the district court did not err

in admitting retrograde extrapolation evidence to estimate Nash’s level of

intoxication at the time of the rental transaction.

IV.   R ULE 50 M OTION

                                        20
      Carco asserts that the district court erred in denying its motion for a

directed verdict because the record contains no evidence establishing that

Carco knew or should have known that Nash was intoxicated at the time of

the rental transaction. We review de novo a district court’s denial of a Rule

50 motion for judgment as a matter of law, using the same standard as the

district court. Weese v. Schukman, 98 F.3d 542, 547 (10th Cir. 1996). A

party is entitled to judgment as a matter of law if construing the evidence

and inferences most favorable to the nonmoving party, “the court is certain

the evidence ‘conclusively favors one party such that [a] reasonable [jury]

could not arrive at a contrary verdict.’” Id. (quoting Western Plains Serv.

Corp. v. Ponderosa Dev. Corp., 769 F.2d 654, 656 (10th Cir. 1985)). In a

diversity case such as this, “we examine the evidence in terms of the

underlying burden of proof as dictated by state law.” Vasey v. Martin

Marietta Corp., 29 F.3d 1460, 1463 (10th Cir. 1994)).

      After reviewing the record, we conclude that the record was sufficient

for a reasonable jury to find that Carco knew or should have known that

Nash was intoxicated at the time of the rental transaction. As discussed

above, the plaintiffs’ expert estimated what Nash’s BAC would have been at

the time of the rental transaction, depending on the amount of alcohol he

consumed during the 35 to 45 minute interval between the transaction and


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the accident. The plaintiffs also presented several witnesses who testified

that Nash could not hold his liquor. The plaintiffs called a handwriting

expert to testify that Nash’s signature on the rental agreement was a forgery,

theorizing that the rental clerk had signed Nash’s name because he was too

intoxicated to sign his own name. Under these circumstances, we hold that a

reasonable jury could have found that Carco knew or should have known that

Nash was intoxicated at the time of the rental transactions. Thus, the district

court did not err in denying Carco’s motion for a directed verdict.

      AFFIRMED.

                                       ENTERED FOR THE COURT,


                                       Deanell Reece Tacha
                                       Circuit Judge




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