United States Court of Appeals
                           FOR THE EIGHTH CIRCUIT
                                      ___________

                                      No. 07-3478
                                      ___________

Michael Littleton; Gerri Littleton,       *
                                          *
             Plaintiffs/Appellees,        *
                                          *
      v.                                  *
                                          *
Brandon McNeely,                          *
                                          *
             Defendant/Appellant,         *
                                          *
_____________________                     *   Appeal from the United States
                                          *   District Court for the
Brandon McNeely,                          *   Western District of Missouri.
                                          *
             Third Party                  *
             Plaintiff/Appellant,         *
                                          *
       v.                                 *
                                          *
Robert Smedley,                           *
                                          *
             Third Party                  *
             Defendant/Appellee,          *
                                          *
Lisa A. Smedley,                          *
                                          *
             Third Party Defendant.       *
                                          *
                                     ___________

                               Submitted: October 15, 2008
                                  Filed: April 9, 2009
                                   ___________

Before RILEY, BOWMAN, and COLLOTON, Circuit Judges.
                                    __________

RILEY, Circuit Judge.

      This case arises from the collision of two boats on the Lake of the Ozarks on
June 19, 2005. One boat was driven and occupied by Brandon McNeely (McNeely).
The other boat was owned by Robert Smedley and occupied by Robert Smedley,
Michael Littleton, and their wives, Lisa Smedley and Gerri Littleton.

       A jury found McNeely 45% at fault for the collision and Michael Littleton, who
had been driving Robert Smedley’s boat moments before the collision, 55% at fault.
McNeely appeals, arguing the district court erred by (1) denying his motion for
judgment as a matter of law on his contribution claim against Robert Smedley,
(2) limiting discovery and excluding photographs at trial, (3) allowing a false closing
argument, (4) refusing a jury instruction, (5) barring evidence of violation of a statute,
and (6) precluding expert testimony. We affirm in part and reverse in part.

I.     BACKGROUND
       The Smedleys and Littletons arrived at the Lake of the Ozarks on Friday, June
17, 2005, for a three-day weekend. Robert Smedley brought his 19-1/2 foot 1993
Crownline boat. On the afternoon of Sunday, June 19, 2005, the group shopped and
ate lunch, then got on the boat around 3:00 or 4:00 p.m. They proceeded to a cove,
where Robert Smedley drank beer. Michael Littleton also consumed three or four
beers. At the cove, the Smedleys discussed their marriage. Lisa Smedley had filed


                                           -2-
for divorce before the trip, and Robert Smedley was hoping to reconcile. Meanwhile,
the Littletons swam nearby. During their discussion, Lisa Smedley told Robert
Smedley she intended to go through with the divorce. Robert Smedley became
distraught and emotional.

       The group went to the Salty Dog restaurant around 8:00 or 8:30 p.m. Michael
Littleton drove the boat to the restaurant. Smedley drank another beer or two at the
Salty Dog. The Littletons both testified Gerri Littleton did not consume any alcohol
that day. Michael Littleton did not consume alcohol at dinner. Upon leaving the Salty
Dog, Robert Smedley asked Michael Littleton to drive the boat because Robert
Smedley was distraught and had consumed alcohol. Michael Littleton agreed to drive
the boat. The group intended to return to the Tan-Tar-A Resort where they were
staying. It was dark outside. As they left the restaurant, Robert Smedley testified he
placed the pole light in the back of the boat and told Michael Littleton how to turn on
the lights. Michael Littleton drove the boat, controlling the speed and route of the
boat, and Robert Smedley did not provide any further direction or assistance in driving
the boat after Michael Littleton backed the boat out of the slip. The Smedleys rode
in the back seat, arguing.

       About twenty minutes after leaving the Salty Dog, Michael Littleton stopped
the boat because he was lost. As the Littletons and Smedleys were attempting to
determine their location, the boat was struck by a 26 foot Formula Thunderbird boat
operated by 20-year-old McNeely. The Littletons and Smedleys testified they did not
see McNeely’s boat before it struck them. McNeely told a water patrol officer on the
scene he was driving his boat and suddenly heard a “huge thud.” McNeely testified
he did not see Robert Smedley’s boat before he hit it, and he did not see any lights on
Robert Smedley’s boat. When McNeely turned around, he saw Robert Smedley’s
boat was capsizing and heard a woman screaming for help. McNeely called 911 and
helped get the Littletons and Smedleys out of the water. At the time of the collision,
McNeely testified he was going around 20 miles per hour. When the two boats

                                         -3-
collided, the Littletons and Smedleys claim no one was in the driver’s seat of Robert
Smedley’s boat and no one was near the controls. The Littletons and Smedleys were
injured.

      The Littletons sued McNeely in Missouri state court. McNeely removed the
case to federal court based on diversity jurisdiction, asserting counterclaims for
contribution against the Littletons and a third party complaint against Smedley for the
imputed negligence of Michael Littleton.1 The jury determined Michael Littleton was
55% at fault, McNeely was 45% at fault, Gerri Littleton was 0% at fault, and Robert
Smedley was 0% at fault. The district court did not instruct the jury to make a finding
whether Michael Littleton’s negligence should be imputed to Robert Smedley.

II.   DISCUSSION
      A.      Imputed Negligence
      The parties agree Missouri law governs this diversity action. See General Elec.
Capital Corp. v. Union Planters Bank, N.A., 

, 1053 (8th Cir. 2005). We
review de novo the district court’s interpretation of Missouri law. 

substantive issues of state law, we are bound by the decisions of the Missouri Supreme
Court. See Bass v. Gen. Motors Corp., 

, 846-47 (8th Cir. 1998).

       McNeely argues Michael Littleton’s negligence should be imputed to Robert
Smedley because Robert Smedley owned the boat, was a passenger at the time of the
collision, and had a right to control the boat at the time of the collision. Robert
Smedley claims there were factual disputes regarding whether Robert Smedley was
in a joint venture with Michael Littleton at the time of the collision. Because
McNeely failed to submit a jury instruction on joint venture, Robert Smedley argues
McNeely waived the argument Michael Littleton’s negligence should be imputed to


      1
        Lisa Smedley was granted summary judgment because she had no ownership
interest in the boat.

                                         -4-
Robert Smedley. McNeely asserts he was not required to submit a joint venture
instruction, or any instruction at all, because Robert Smedley’s ownership and
presumed right to control the boat makes Robert Smedley liable for Michael
Littleton’s negligence as a matter of law.

       In his third party complaint, McNeely asserted Robert Smedley was responsible
for Michael Littleton’s negligence under theories of joint venture and captain of the
ship, and alleged Robert Smedley owned the boat and “the fault [of Michael Littleton]
is imputed.” McNeely submitted a jury instruction on the captain of the ship theory,
but McNeely did not propose a joint venture instruction.2 Because McNeely did not
propose a jury instruction on joint venture or any other theory of imputed liability,
McNeely waived his right to submit the matter to the jury, unless we determine the
district court’s refusal to instruct the jury on imputed liability was plain error. See
Slidell, Inc. v. Millennium Inorganic Chems., Inc., 

, 1056 (8th Cir.
2006) (explaining failure to propose a jury instruction results in plain error review);
see also Whitted v. Healthline Mgmt., Inc., 

, 479 (Mo. Ct. App. 2002)
(declaring failure to submit an instruction waives any point of error a party may have
regarding that claim). However, McNeely did move for judgment as a matter of law
on the issue of imputed liability. The district court denied McNeely’s motion. Thus,
the question before this court is whether the district court erroneously denied
McNeely’s motion for judgment as a matter of law.

      In ruling on a motion for judgment as a matter of law, the inquiry is “whether
the evidence presents a sufficient disagreement to require submission to a jury or

      2
        The district court did not submit McNeely’s captain of the ship instruction
because the court determined that the instruction was based on federal admiralty law,
and the Lake of the Ozarks was not a navigable waterway. See Three Buoys
Houseboat Vacations U.S.A., Ltd. v. Morts, 

, 779 (8th Cir. 1990). Thus,
the jury received no instruction, under any theory, for imputing Michael Littleton’s
negligence to Robert Smedley.


                                         -5-
whether it is so one-sided that one party must prevail as a matter of law.” Anderson
v. Liberty Lobby, Inc., 

, 251-52 (1986). The court should grant judgment
as a matter of law “only when all of the evidence points one way and is ‘susceptible
of no reasonable inference sustaining the position of the nonmoving party.’” Smith
v. World Ins. Co., 

, 1460 (8th Cir. 1994) (quoting White v. Pence, 

, 779 (8th Cir. 1992)).

      The district court denied McNeely’s motion for judgment as a matter of law
because it determined there was a factual dispute as to whether Robert Smedley had
equal control of the boat at the time of the collision. This determination was
erroneous. Under Missouri law, the critical inquiry is not whether Robert Smedley
actually had equal control of the boat at the time of the collision, but whether Robert
Smedley had a right of control and whether an agency relationship existed between
Robert Smedley and Michael Littleton. Recently, the Missouri Supreme Court
addressed the circumstances under which a driver’s negligence can be imputed to an
owner-passenger of a vehicle. See Bach v. Winfield-Foley Fire Prot. Dist., 

605, 606 (Mo. 2008) (en banc). In Bach, Nephew used Aunt’s car to drive her to
a widows’ meeting. 

Aunt asked Nephew to drive her car because Aunt did
not know how to drive and had no license. 

a fire truck, which
was parked partially in his lane attending to another accident, and Aunt was injured.
 

Nephew and the Winfield-Foley Fire Protection District (Fire
District), arguing the Fire District failed to exercise adequate care by parking the fire
truck in a lane of traffic, and failed to warn of the blocked roadway. 

District argued Aunt, as the owner of the car, was responsible for Nephew’s
contributory fault as if it were her own because Aunt and Nephew were engaged in
a joint venture or joint journey at the time of the collision. 

instructions
given by the district court did not ask the jury to determine whether Nephew was
acting as Aunt’s agent or whether a joint enterprise existed. Instead, the district court


                                          -6-
determined Nephew’s fault was attributable to Aunt as a matter of law, instructing the
jury “that in assessing any percentage of fault against Aunt, Nephew’s fault should be
attributed to her.” 

(emphasis added). The jury found Aunt suffered
$100,000 in damages, apportioning 15% fault to the Fire District and 85% fault to
Aunt. 

Aunt argued Nephew’s negligence should not have been imputed
to her because, even though she owned the automobile, she had no right to control the
automobile as she did not know how to drive. 

The Missouri Supreme
Court disagreed. The court declared the issue to be resolved was whether a
principal/agent relationship existed between Aunt and Nephew, explaining agency is
a fiduciary relationship where the agent consents to act on behalf of the principal and
subject to the principal’s control. 

In an agency relationship, “the principal
only has the right to control the ends of the agent’s activities; the principal does not
have the right to control or direct the physical movements of [his] agent in
accomplishing the final result.” 

v. Nat’l Life & Accident Ins. Co.
of Nashville, Tenn., 

, 271 (Mo. 1941)). No formal contract or
appointment is necessary to create an agency relationship. 

agency
relationship may be a “wholly gratuitous undertaking,” and “consent may be
manifested and the relationship may be created by words and conduct . . . even if the
parties did not intend to create the legal relationship or to subject themselves to the
liabilities that the law imposes as a result.” 

       The Bach court further explained, so long as the agent is acting with actual
authority, a principal is responsible for his agent’s acts. 

v. Helm
Plumbing and Elec. Contractors, Inc., 

, 660 (Mo. Ct. App. 2002)).
“Specifically, when a person operates an automobile of another while the owner is a
passenger, acquiescing in the operation, there is a presumption that the driver is the
agent of the owner and within the scope of his agency.” 

v.
DeBlaze, 

, 725 (Mo. Ct. App. 1983)). “[T]he principal must have a


                                          -7-
‘right to control’ the agent.” 

v. Simmons, 

, 362
(Mo. 1963)).

       The Bach court rejected Aunt’s argument that no agency relationship existed
because she had no realistic right to control the vehicle. The court explained, “there
was sufficient evidence to establish a basis for finding a principal/agent relationship
to impute liability from Nephew to Aunt,” because (1) Aunt was the sole owner of the
vehicle, (2) Nephew was driving with Aunt’s authorization, (3) Nephew had agreed
to drive Aunt wherever she wanted to go, in exchange for personal use of the vehicle,
and (4) Nephew was driving “at Aunt’s behest and subject to her direction as to where
to go.” 

       There is no dispute Robert Smedley was the sole owner of the boat and asked
Michael Littleton to drive the boat upon leaving the Salty Dog, and Michael Littleton
agreed. Robert Smedley asked Michael Littleton to drive because Robert Smedley
had been drinking alcohol and he was distraught and emotional. As the boat left the
Salty Dog, Robert Smedley put the pole light in the back of the boat and told Michael
Littleton how to turn on the lights. Robert Smedley and Michael Littleton both
intended for Michael Littleton to drive the boat to the Tan-Tar-A Resort. Robert
Smedley then sat in the back of the boat arguing with Lisa Smedley until Michael


      3
         In Bach, the court distinguished Stover v. Patrick, 

(Mo. 1970)
(per curiam), which Smedley relies upon in his brief and which the district court relied
upon in denying McNeely’s motion for judgment as a matter of law. Stover involved
spouses who were co-owners of an automobile. 

. Stover
reasoned joint ownership of an automobile, by itself, was insufficient to impute the
negligence of a driver-spouse to a passenger-spouse. 

459 S.W.2d
at 401). The Bach court observed, “[u]nlike in Stover, Aunt and Nephew were not co-
owners of the automobile,” and explained Stover’s holding was “limited to where
there is an ‘absen[ce of] evidence of other facts which establish a basis for imposing
liability on the passenger-wife for acts of her driver-husband.” 

459
S.W.2d at 401).

                                          -8-
Littleton stopped the boat because he was lost. Although Michael Littleton controlled
the speed and route of the boat, and Robert Smedley did not provide any further
direction or assistance in driving the boat after Michael Littleton backed it out of the
slip, no evidence was presented to suggest Robert Smedley lacked the right to control
the ends of Michael Littleton’s activities. Robert Smedley presumably could have
asked Michael Littleton to relinquish control of the boat at any time.

       These undisputed facts are sufficient to establish, as a matter of law, that a
principal/agent relationship existed between Michael Littleton and Robert Smedley.
Because Michael Littleton acted with actual authority and Robert Smedley had the
right to control the ends of Michael Littleton’s activities, Michael Littleton’s liability
is imputed to Robert Smedley as a matter of law.4 We therefore reverse the district
court’s denial of McNeely’s motion for judgment as a matter of law.




      4
        Smedley argues McNeely did not explicitly plead an agency theory in his third
party complaint. McNeely pled only captain of the ship and joint venture. The Fire
District in Bach similarly “argued that Aunt’s own negligence contributed to her
injuries, as she and Nephew were engaged in a joint venture or joint journey at the
time of the accident.” Bach, 

at 607. The court recognized “[t]he District
misclassifie[d] Aunt and Nephew’s relationship as a joint venture,” and the joint
venture “doctrine [was] inappropriate because there was no community of pecuniary
interest between Aunt and Nephew in this journey.” 

(citing Manley v.
Horton, 

, 260 (Mo. 1967)). Despite the Fire District’s apparent failure
to plead an agency theory, the Bach court held Nephew’s liability was imputed to
Aunt. 

At least one other Missouri case notes, although the term “joint
venture” usually arises “in a commercial or business trip context . . . misnomer of the
legal relationship between [the] plaintiff and her driver did not constitute reversible
error” under the circumstances of the case. 

.

                                           -9-
      B.      McNeely’s Motion for a New Trial
              1.     Alleged Party Cove Evidence
       McNeely claims the district court erred by excluding from evidence certain
photos salvaged from a camera in Robert Smedley’s boat which McNeely claims
depict the Smedleys and Littletons drinking at Party Cove, an area Michael Littleton’s
counsel described as notorious for drinking alcohol, nudity, “debauchery and
craziness.” The Littletons and Smedleys deny being at Party Cove on the day of the
collision. Gerri Littleton denies drinking any alcohol on the day of the collision.
McNeely also objects to the district court’s ruling prohibiting him from mentioning
the phrase “Party Cove” at trial because the district court found the term “Party Cove”
would be highly prejudicial and of no probative value. McNeely moved for a new
trial on these issues.

       “‘We review the denial of a motion for a new trial for a clear abuse of
discretion.’” Harrison v. Purdy Bros. Trucking Co., 

, 351 (8th Cir. 2002)
(quoting Duty v. Norton-Alcoa Proppants, 

, 495 (8th Cir. 2002)). The
district court’s evidentiary rulings are also reviewed for clear abuse of discretion. See
United States v. Pirani, 

, 555 (8th Cir. 2005) (en banc) (citing United
States v. Montano-Gudino, 

, 505 (8th Cir. 2002)). We will not reverse
based on erroneous evidentiary rulings “absent a showing that the ruling had a
substantial influence on the jury’s verdict.” Harris v. Chand, 

, 1139
(8th Cir. 2007) (citing McPheeters v. Black & Veatch Corp., 

, 1101 (8th
Cir. 2005)). “Although relevant, evidence may be excluded if its probative value is
substantially outweighed by the danger of unfair prejudice, confusion of the issues,
or misleading the jury, or by considerations of undue delay, waste of time, or needless
presentation of cumulative evidence.” Fed. R. Evid. 403.

       McNeely contends the alleged Party Cove photos should have been admitted
into evidence because, contrary to Gerri Littleton’s testimony she drank no alcohol on
the day of the collision, some of the photos show Gerri Littleton drinking alcohol on


                                          -10-
the day of the collision. We disagree. The photos do not depict anyone actually
drinking anything, and it is unclear whether the photos even depict Gerri Littleton
holding an alcoholic beverage. Several of the photos show a woman holding a bottle
covered in a green holder, and another photo shows a different woman holding a bottle
largely obscured by her hand. The court assumes the women in these photos are Gerri
Littleton and Lisa Smedley, but McNeely has not identified for this court which
woman is Gerri Littleton and which is Lisa Smedley. The photos do not reveal
whether the bottles contain alcoholic or non-alcoholic beverages. Even if the photos
did show Gerri Littleton drinking alcohol, we fail to see how that fact would have had
any significant impact on the verdict. McNeely never claimed Gerri Littleton was the
operator of the boat or that her alleged alcohol consumption contributed to the
collision in any way.

       Further, there is no date stamp on the photos, and McNeely offered no evidence
to establish whether the photos were taken on the day of the collision or another day
that weekend. It is also unclear whether the photos were taken at Party Cove or some
other location on the water. The photos do, however, provide a potentially prejudicial
depiction of two women, presumably Gerri Littleton and Lisa Smedley, on a boat with
their bikini tops off. The photos also contain other images of unknown women with
their tops off. It is readily apparent jurors might consider such conduct lewd,
offensive, or immoral. If these photos had any probative value at all—and we see
none—the district court certainly did not abuse its discretion by determining any
minor probative value was far outweighed by the potential for prejudice resulting from
the jury’s disapproval of the photos.5


      5
        McNeely also claims the district court erred by “limiting discovery” of the
alleged Party Cove photos. It is unclear what error McNeely claims in the discovery
of the photos. Because McNeely’s counsel was allowed to view the photos and the
district court reopened discovery to allow McNeely to depose the Smedleys to
determine whether they could identify the people in the photographs, we see no error
in the district court’s discovery ruling.

                                        -11-
       The district court also did not err by prohibiting McNeely from using the phrase
“Party Cove” at trial. The only alleged operator of Robert Smedley’s boat, Michael
Littleton, admitted going to a cove and drinking alcohol on the day of the collision.
Whether Michael Littleton drank alcohol at Party Cove or some other place has no
bearing on his negligence or percentage of fault. The collision did not occur at Party
Cove, and it occurred many hours after McNeely claims the Littletons and Smedleys
visited Party Cove. In our view, the only purpose of mentioning the phrase “Party
Cove” would be to suggest to the jury the Littletons and Smedleys were engaged in
offensive or immoral conduct sometime that weekend. Because the location where
Michael Littleton’s drinking occurred was at best a tangential issue, the district court
did not abuse its considerable discretion by determining the minor relevance, if any,
of Party Cove was far outweighed by the prejudicial inferences carried by the phrase.

               2.    Closing Argument
        McNeely next argues the district court erred by allowing Gerri Littleton’s
counsel to argue in closing argument that Gerri Littleton was tested for alcohol at the
hospital and her medical records reflected no ethyl alcohol in Gerri Littleton’s blood.
In his closing argument, McNeely’s counsel argued, “[Y]ou folks have the medical
records. You can take a look at them if you have any doubt. There’s no report there
at all that says she had nothing to drink. The truth is they didn’t run a blood alcohol
[test] on her.” Gerri Littleton’s counsel countered in his own closing argument that
Gerri Littleton’s “medical records . . . [do not] say a word about ethyl alcohol. If you
have ethyl alcohol, it pops up on the printout, ethyl alcohol.” Gerri Littleton’s counsel
based his statements on a hospital printout of Gerri Littleton’s blood tests that
contained no mention of ethyl alcohol. On the other hand, Michael Littleton’s hospital
printout, which followed the same format, contained a notation of .111 blood alcohol
content.

      “[W]hen a new trial motion is based on improper closing arguments, a new trial
should be granted only if the statements are ‘plainly unwarranted and clearly


                                          -12-
injurious’ and ‘cause prejudice to the opposing party and unfairly influence a jury’s
verdict.’” 

(quoting Alholm v. Am. Steamship Co., 

, 1181 (8th Cir. 1998)) (alterations omitted). After comparing Gerri Littleton’s
printout to Michael Littleton’s printout, the district court found it was a reasonable
inference that the same blood test had been administered and Michael Littleton’s
showed .111 ethyl alcohol because alcohol was present in his bloodstream. The
district court further found it was reasonable to infer the absence of an ethyl alcohol
notation meant Gerri Littleton’s blood was tested, and there was no alcohol present
in her blood. We agree more than one reasonable inference can be drawn from Gerri
Littleton’s medical records. McNeely apparently never produced a witness to testify
which tests were actually given to Gerri Littleton. Furthermore, Gerri Littleton’s
blood alcohol content was of such minimal significance to the litigation that any
alleged error was harmless, and certainly was not so prejudicial and injurious as to
influence unfairly the jury’s verdict. The district court did not abuse its discretion by
permitting Gerri Littleton’s counsel to argue Gerri Littleton’s medical records
reflected no ethyl alcohol in her bloodstream.

              3.     Refusal of McNeely’s Intoxication Instruction
       McNeely also contends he is entitled to a new trial because the district court
refused to give one of McNeely’s proposed instructions, which read: “Plaintiff
Michael Littleton drove while intoxicated to the extent that his driving ability was
impaired.” See M.A.I. 17.21. McNeely did not specifically object to the district
court’s refusal to give his proposed intoxication instruction.6 We normally review
jury instructions for abuse of discretion, determining “‘whether the instructions fairly


      6
       McNeely “object[ed] to instruction 13 because it fails to submit the issue to the
jury with regard to fault on the part of Michael Littleton for failing to maintain proper
control of the boat to avoid the collision and for driving under the influence of
alcohol.” Objecting to the intoxication issue in a different instruction is not the same
as asking the district court to give another specific instruction. In any event, our
conclusion would be the same under an abuse of discretion review.

                                          -13-
and adequately submitted the issues to the jury.’” Crump v. Versa Prods., Inc., 

, 1107 (8th Cir. 2005) (quoting Bennett v. Hidden Valley Golf and Ski, Inc.,

, 873 (8th Cir. 2003)). However, “[a] party’s failure to object to jury
instructions results in a waiver of that objection, absent a showing of plain error.”
Niemiec v. Union Pac. R.R. Co., 

, 857-58 (8th Cir. 2006).

       McNeely argued throughout the trial that Michael Littleton was drunk and this
was the reason Michael Littleton did not turn on the boat’s headlights or keep a careful
lookout. The instructions given by the district court permitted the jury to assess fault
against Michael Littleton if he failed to keep a proper lookout or failed properly to
display his headlights. McNeely’s proposed instruction presented no link between
Michael Littleton’s intoxication and how his intoxication allegedly contributed to or
caused the collision. Because Michael Littleton’s alcohol consumption was only
relevant to the issue of not keeping a proper lookout or not turning on the lights,
McNeely was not necessarily entitled to a separate instruction permitting the jury to
assess fault against Michael Littleton based solely on his intoxication, with no
reference to how his intoxication may have caused the collision. See M.A.I. 17.21
Committee Comment (recognizing, “[t]here must be evidence to support a finding of
proximate cause between defendant’s intoxication and plaintiff’s damages”) (citing
Bowman v. Heffron, 

, 273 (Mo. 1958)). The district court did not
commit error, plain or otherwise, by refusing to submit McNeely’s proposed
intoxication instruction.

               4.     Evidence of Violation of a Missouri Statute
       McNeely argues he is entitled to a new trial because the district court
erroneously excluded evidence that Michael Littleton violated a Missouri statute.
McNeely did not plead violation of a statute as the basis for his contribution claim, nor
did McNeely ever specify for the district court which Missouri statute Michael
Littleton allegedly violated. McNeely neither offered evidence, nor made an offer of
proof at trial, that Michael Littleton violated a statute. Nowhere in his appellate brief


                                          -14-
does McNeely cite a specific Missouri statute. We will presume, as the district court
did, McNeely intends Mo. Rev. Stat. § 306.111, which prohibits driving a vessel on
Missouri lakes while intoxicated.

       Even if we assume this issue were properly pled, properly presented to the
district court, and properly preserved for appeal, the district court did not err by
determining McNeely was not allowed to present evidence or instruct the jury on
Michael Littleton’s alleged violation of Mo. Rev. Stat. § 306.111. Michael Littleton
was never arrested or charged with violating Mo. Rev. Stat. § 306.111 or any other
statute. The district court allowed McNeely to argue numerous times that Michael
Littleton was intoxicated. The jury’s finding Michael Littleton 55% at fault for the
collision strongly suggests the jury indeed placed significant weight on Michael
Littleton’s intoxication. McNeely fails to explain how Michael Littleton’s alleged
statutory violation would have resulted in a more favorable verdict. In our view,
allowing McNeely to argue Michael Littleton was guilty beyond a reasonable doubt
of criminal conduct would have been cumulative to the intoxication evidence already
presented and also potentially would confuse the jury. See Fed. R. Evid. 403. We
therefore conclude the district court did not err by excluding evidence of Michael
Littleton’s alleged violation of Mo. Rev. Stat. § 306.111.

              5.    Expert Testimony
       Finally, McNeely contends he is entitled to a new trial because the district court
erroneously limited the testimony of McNeely’s expert, Dr. Curtis Klaassen (Dr.
Klaassen). “‘Decisions concerning the admission of expert testimony lie within the
broad discretion of the trial court, and these decisions will not be disturbed on appeal
absent an abuse of that discretion.’” Anderson v. Raymond Corp., 

, 523
(8th Cir. 2003) (quoting Peitzmeier v. Hennessy Indus., Inc., 

, 296 (8th
Cir. 1996)). Even if the district court’s evidentiary decision were an abuse of
discretion, any error “must affect a party’s substantial rights to warrant a new trial.”
Williams v. City of Kansas City, Mo., 

, 755 (8th Cir. 2000). “Error may


                                          -15-
not be predicated upon a ruling excluding evidence unless . . . ‘the substance of the
evidence was made known to the court by offer [of proof] or was apparent from the
context within which questions were asked.’” Strong v. Mercantile Trust Co., 

, 431 (8th Cir. 1987) (quoting Fed. R. Evid. 103(a)(2)).

        McNeely claims Dr. Klaassen should have been allowed to testify “on the
exponential effects of alcohol consumption and . . . as to standards in other
jurisdictions with regard to appropriate levels of blood alcohol.” McNeely made no
offer of proof at trial as to what the substance of Dr. Klaassen’s testimony would have
been on these issues. We therefore conclude McNeely failed to preserve the alleged
error for appeal.7 See 

       We reverse the district court’s denial of McNeely’s motion for judgment as a
matter of law on McNeely’s contribution claim against Robert Smedley, and affirm
the district court on all other issues.
                          ______________________________




       7
        Even on appeal, McNeely fails to inform the court what other jurisdictions’
standards Dr. Klaassen planned to discuss or what Dr. Klaassen intended to say about
other jurisdictions’ standards regarding “appropriate levels of blood alcohol.” It is
therefore impossible for this court to evaluate whether Dr. Klaassen’s testimony was
relevant in this case, or the degree of any relevance, much less whether McNeely’s
substantial rights were affected by the district court’s exclusion of such testimony.


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