Drake v. Crete Carrier Corporation dba Shaffer Trucking et al

IN THE UNITED STATES DISTRICT COURT
FOR THE EASTERN DISTRICT OF TEXAS
SHERMAN DIVISION
CASEY A. DRAKE
v.
CRETE CARRIER
CORPORATION, et al.
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NO. 4:23-CV-01021-BD
MEMORANDUM OPINION AND ORDER
Defendants Crete Carrier Corporation and Reuben Robert Shaffer moved to exclude two of
plaintiff Casey A. Drake’s expert witnesses, Mr. Robert Kelly and Dr. Jack Leifer. Dkts. 49 (Kelly),
50 (Leifer); see Dkts. 52 (response to Dkt. 50), 53 (response to Dkt. 49), 62 (supplemental motion
to exclude Leifer), 64 (joint status report), 65 (supplemental notice by the defendants). The court
held a hearing on the motions. Minute Entry for Dec. 16, 2025. It will grant in part and deny in part
the motion to exclude Kelly, Dkt. 49, and deny the motion to exclude Leifer, Dkt. 50.
BACKGROUND
Drake sued the defendants for personal injuries arising from a vehicle collision. Dkt. 9. Drake
was riding in a car driven by his niece, Erica Diehl. Dkt. 48 at 3. Shaffer was driving a tractor-trailer.
Dkt. 44 at 2. As the two drivers passed a wrecked vehicle, they collided. Id.; Dkt. 48 at 3. Drake
retained Kelly and Leifer as experts to testify that Shaffer caused the collision. Dkt. 40. The
defendants moved to exclude their testimony. Dkts. 49, 50.
LAW
Federal Rule of Evidence 702 governs the admissibility of expert testimony. It was amended in
2023 to provide:
A witness who is qualified as an expert by knowledge, skill, experience, training, or
education may testify in the form of an opinion or otherwise if the proponent
demonstrates to the court that it is more likely than not that:
(a) the expert’s scientific, technical, or other specialized knowledge will help the
trier of fact to understand the evidence or to determine a fact in issue;
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(b) the testimony is based on sufficient facts or data;
(c) the testimony is the product of reliable principles and methods; and
(d) the expert’s opinion reflects a reliable application of the principles and methods
to the facts of the case.
The 2023 advisory committee note explains that the amendment was meant to (1) “clarify and
emphasize that expert testimony may not be admitted unless the proponent demonstrates to the
court that it is more likely than not that the proffered testimony meets the admissibility
requirements set forth in the rule” and (2) “emphasize that each expert opinion must stay within
the bounds of what can be concluded from a reliable application of the expert’s basis and
methodology.”
In Daubert v. Merrell Dow Pharmaceuticals, the Supreme Court instructed courts to serve as
gatekeepers when applying Rule 702 to determine whether expert testimony should be presented
to the jury. 509 U.S. 579, 589–95 (1993). Courts must “make certain that an expert, whether basing
testimony upon professional studies or personal experience, employs in the courtroom the same
level of intellectual rigor that characterizes the practice of an expert in the relevant field.” Kumho
Tire Co. v. Carmichael, 526 U.S. 137, 152 (1999). That “gate-keeping obligation applies to all types
of expert testimony, not just scientific testimony.” Pipitone v. Biomatrix, Inc., 288 F.3d 239, 244
(5th Cir. 2002).
Under the Daubert test, which examines the underlying theory on which an expert opinion is
based, “[t]he proponent need not prove to the judge that the expert’s testimony is correct, but she
must prove by a preponderance of the evidence that the testimony is reliable.” Moore v. Ashland
Chem., Inc., 151 F.3d 269, 276 (5th Cir. 1998). The court’s inquiry is flexible, in that “[t]he
relevance and reliability of expert testimony turns upon its nature and the purpose for which its
proponent offers it.” United States v. Valencia, 600 F.3d 389, 424 (5th Cir. 2010).
The Fifth Circuit explained several decades ago that, “[a]s a general rule, questions relating to
the bases and sources of an expert’s opinion affect the weight to be assigned that opinion rather
than its admissibility and should be left for the [factfinder’s] consideration.” Viterbo v. Dow Chem.
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Co., 826 F.2d 420, 422 (5th Cir. 1987). And although the 2023 advisory committee note to Rule
702 criticized unspecified judicial decisions concluding that “critical questions of the sufficiency
of an expert’s basis, and the application of the expert’s methodology, are questions of weight and
not admissibility,” it also acknowledged that “[s]ome challenges to expert testimony will raise
matters of weight rather than admissibility even under the [Federal] Rule 104(a) standard,” which
is less permissive than Rule 104(b). Compare Fed. R. Evid. 104(a) (providing that “[t]he court must
decide any preliminary question about whether a witness is qualified, a privilege exists, or evidence
is admissible”) with id. R. 104(b) (providing that “[w]hen the relevance of evidence depends on
whether a fact exists, proof must be introduced sufficient to support a finding that the fact does
exist” and that “[t]he court may admit the proposed evidence on the condition that the proof be
introduced later”). In other words, “once the court has found it more likely than not that the
admissibility requirement has been met, any attack by the opponent will go only to the weight of
the evidence.” Fed. R. Evid. 702, advisory cmte. n. to 2023 amend.
It remains the case that “[v]igorous cross-examination, presentation of contrary evidence, and
careful instruction on the burden of proof are the traditional and appropriate means of attacking
shaky but admissible evidence.” Daubert, 509 U.S. at 596; see also Guy v. Crown Equip. Corp., 394
F.3d 320, 325 (5th Cir. 2004) (explaining that, “[a]lthough the Daubert analysis is applied to ensure
expert witnesses have employed reliable principles and methods in reaching their conclusions, the
test does not judge the expert conclusions themselves”). Although “the district court must act as
a gatekeeper to exclude all irrelevant and unreliable expert testimony, ʻthe rejection of expert
testimony is the exception rather than the rule.’” Puga v. RCX Sols., Inc., 922 F.3d 285, 294 (5th
Cir. 2019) (quoting Fed. R. Evid. 702 advisory cmte. n. to 2000 amend.).
DISCUSSION
I. 	Kelly
The defendants argue that Kelly’s testimony is inadmissible because Kelly is not qualified as a
causation expert, his methods are unreliable, and his opinion regarding Crete’s conduct is based
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on inaccurate facts and not relevant to the issue of causation. Kelly is qualified to and can reliably
speak on causation, but his testimony regarding hiring, recordkeeping, and training is irrelevant to
the claims at issue and will therefore be excluded.
A. Qualification
The defendants argue that Kelly is not qualified to opine on the cause of the collision because
he is not an accident reconstructionist. Dkt. 49 at 6. Drake responds that Kelly’s experience as a
police officer makes him qualified. Dkt. 53 at 5–6. Drake is correct. An expert must be qualified by
his “knowledge, skill, experience, training, or education,” Fed. R. Evid. 702, but he need not have
a particular job title, Williams v. Warren, No. 99-41078, 2001 WL 498501, at *2 (5th Cir. Apr. 10,
2001). A police officer may testify about the cause of a traffic accident if he has sufficient skill and
knowledge. Smith v. Chrysler Grp., LLC, No. 1:15-cv-218, 2017 WL 7788131, at *2 (E.D. Tex. June
8, 2017).
Kelly was a police officer for ten years. Dkt. 53-4 at 1. During that time, he investigated more
than 300 collisions involving commercial vehicles. Dkt. 53-5 at 1. He has certifications specific to
traffic enforcement and is certified as a driving instructor for commercial vehicles. Dkts. 53-2 at 1,
53-4 at 1–2. That all indicates that Kelly has sufficient experience working with commercial
vehicles and investigating collisions involving them to opine on the cause of the collision at issue
here. See Smith, 2017 WL 7788131, at *2 (collecting cases supporting that conclusion).
B. Reliability
The defendants also argue that Kelly’s testimony would be unreliable because he based his
opinion solely on two photographs and did not visit the accident scene, conduct any interviews, or
take any measurements. Dkt. 49 at 6–7. In particular, the defendants argue that Kelly does not have
a reliable basis to testify that
the SUV involved in the previous collision was occupying not only the left-hand
lane but also extended into the right-hand lane as well. This means that it would
have been impossible for Defendant [Shaffer] to maintain his vehicle in the right-
hand lane and pass the previous collision without moving to the shoulder of the
roadway.
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Dkt. 53-2 at 6–7.
Kelly based that opinion on his review of footage recorded by a responding police officer’s body
camera, two frames of which are reproduced in his report. Id.; Dkt. 53 at 8. Those frames appear
to show the hood and front tires of the disabled vehicle extending into the right lane over the dashed
white line that divides the road. Kelly also reviewed the responding officer’s crash report, which
repeated Diehl’s claim that Shaffer moved from the right lane into the right-hand shoulder and
struck her car. Dkt. 53-2 at 6.
As with an expert’s qualifications, whether an expert’s methodology is reliable depends on the
particular circumstances of each case. Kumho Tire Co., 526 U.S. at 150. Reviewing photographs,
especially where, as here, that review is bolstered by other materials, is not necessarily an unreliable
method. In appropriate circumstances, photographs can provide sufficient information for an
expert to apply his knowledge and experience and form an opinion. Bostick v. State Farm Mut. Auto.
Ins. Co., 321 F.R.D. 414, 417 (M.D. Fla. 2017).
Whether a vehicle has space to maneuver is the kind of determination an expert can make based
on his review of photographs and videos alone. By reviewing the images available here, Kelly could
see the amount of unobstructed space in the right lane of traffic and, applying his knowledge,
determine whether or not a tractor-trailer would be able to safely traverse the lane without moving
into the shoulder. That means Kelly’s opinion about the cause of the accident is based on
sufficiently reliable data.
C. Irrelevance of Crete’s conduct
Kelly also stated his opinions about Crete’s hiring of Shaffer, Shaffer’s qualifications, whether
Crete kept adequate records, and whether Shaffer was adequately trained. Dkt. 53-2 at 8–11. The
defendants challenge those opinions as unreliable and as irrelevant to the central issue of causation.
Dkt. 49 at 8–9.
Drake does not assert a direct negligence claim against Crete. He seeks to hold Crete
vicariously liable for Shaffer’s alleged negligence at the time of the collision. Dkt. 9. Whether
Shaffer was qualified, whether Crete kept adequate records, and whether Shaffer was adequately
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trained do not bear on whether Shaffer was negligent at that time. Evidence that has no tendency
to make a material fact more or less probable is not admissible. Fed. R. Evid. 401–02. As such,
Kelly’s opinions about hiring, qualifications, record keeping, and training will be excluded.
II. Leifer
The defendants argue that Leifer is not qualified to testify about the cause of the collision and
that his testimony is unreliable. Dkt. 50. They are wrong on both counts.
A. Qualification
The defendants argue that Leifer, like Kelly, is not qualified to opine on the cause of the
collision because he is not an accident reconstructionist. Dkt. 50 at 6. (They also argue that Leifer
is not qualified because he is not a medical professional. Id. But that argument goes to the cause of
Drake’s injuries, not the cause of the collision. Because the parties have stipulated that Leifer will
not testify about the cause of any injury, Dkt. 64 at 1, that argument need not be addressed.)
As an initial matter, it is not clear that Leifer is not an accident reconstructionist. His
curriculum 	vitae 	(“CV”) 	indicates 	that 	he 	is 	an 	affiliate 	of 	the 	Society 	of 	Accident
Reconstructionists and a member of the Texas Association of Accident Reconstruction Specialists.
Dkt. 52-7 at 8. Describing his license to perform engineering services, Leifer explains that he has
“provided expert opinions requiring knowledge in impact computation, damage assessment from
photographs, motion analysis, materials evaluation.” Id. He is responsible for numerous
publications and presentations about topics related to accident reconstruction, id. at 2–7, and he
has participated in continuing education courses dedicated to accident reconstruction, id. at 9.
That sure makes him sound like an accident reconstructionist.
But even assuming he does not technically fit that description, his job title is not determinative.
See supra Part I.A. His report discusses, based on the damage to Diehl’s car and the conditions of
the roadway, the forces that likely applied to the vehicles and the relative speeds that would
probably have generated those forces. Dkt. 52-5 at 10–11. An accident reconstructionist or not,
Leifer is a mechanical engineer who has taught university courses relating to dynamics, kinematics,
and statics and has published multiple works related to the relationships between impacts and
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force. Dkt. 52-5; see McGraw-Hill Dictionary of Scientific and Technical Terms 668 (6th ed. 2003)
(defining “dynamics” as a “branch of mechanics which deals with the motion of a system of
material particles under the influence of forces”); id. at 1153 (defining “kinematics” as “the study
of the motion of a system of material particles without reference to the forces which act on the
system”); id. at 2022 (defining “statics” as a “branch of mechanics which treats of force and force
systems abstracted from matter, and of forces which act on bodies in equilibrium”).
Leifer’s observations are based in physics, and his CV reflects substantial knowledge and
experience in the relevant scientific fields. He is well-qualified to opine and reasonably apply his
observations to the facts of this case.
B. Reliability
The defendants make three arguments that Leifer’s methods and data are unreliable. First,
they assert that Leifer relied on a scientific study that is old and distinguishable from the facts of
this case. Dkt. 50 at 7. Second, they argue that, during his deposition, Leifer could not “[s]tate
[w]ith [c]ertainty” how the collision occurred. Dkt. 62 at 1. Finally, they note that Leifer could also
not initially state at his deposition what source supported his opinion that lanes of traffic are
generally 11–12 feet wide. Id. at 4. The second two of those arguments were raised only in a
supplemental motion filed after the deadline to object to expert testimony, Dkt. 62; see Dkt. 39
(then-operative scheduling order), raising a question about their timeliness. But the court need not
consider that question, which Drake did not raise, because none of the arguments has merit.
As to the first argument, both the study Leifer relies on and his own opinion are grounded in
physics. The laws of p hysics operated the same way in 2002, when the challenged study was
published, as they did when the collision at issue here occurred. See Robert Thomson & Jarkko
Valtonen, Vehicle Impacts in V-Shaped Ditches, 1797 Transp. Rsch. Rec.: J. of Transp. Rsch. Bd.,
no. 1, 2002, at 1. And although the jury will be free to weigh the differences between the collision
in this case and the experimental conditions in the 2002 study, that study could still inform an
expert about how force is exerted on vehicles, such that the expert could apply that knowledge to
the facts here. That is what Leifer did.
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As to the second argument, Leifer testified that the collision might have occurred in one of
three ways: Shaffer’s tractor-trailer was moving to the right, Diehl’s car was straddling the fog line,
or Diehl was moving to the left. Dkt. 62-1 at 9–10. Although Leifer conceded that any of those three
scenarios was possible, he testified that it is most likely that Shaffer was moving to the right at the
time of the collision. Id. at 10–12. That opinion was based on his opinions that Shaffer’s vehicle
was likely moving faster than Diehl’s and that it would have been unsafe for Shaffer to drive straight
through the right lane without moving to the shoulder. Dkt. 53-5 at 10–11. Leifer did not say that
he knew with certainty what happened, but “it would be unreasonable to conclude that the subject
of scientific testimony must be ʻknown’ to a certainty; arguably, there are no certainties in
science.” Daubert, 509 U.S. at 590.
As to the defendants’ final argument, Leifer’s inability to recite, on the spot during his
deposition, a source stating that traffic lanes are generally 11–12 feet wide does not impugn his
report’s validity. Leifer testified that he used the standard width of a traffic lane to calculate an
approximate location of the collision. Dkt. 65-1 at 36. Although he also testified that traffic lanes
are generally 11–12 feet wide, id., that figure does not appear in his report. And although he could
not to provide a citation for the figure when he was first asked about it, he returned with a citation
after a break. It would be unreasonable to deem his testimony unreliable just because he had not
memorized the citation for a figure, particularly one that did not appear in his report. In any event,
the actual width of the lanes according to the defendants, 12.5 feet, Dkt. 62-1 at 7–8, falls within
the margin of error Leifer allowed, id. at 37. Leifer’s testimony need only be reliable, not
unquestionable, for the jury to properly weigh it. Paz v. Brush Engineered Materials, Inc., 555 F.3d
383, 388 (5th Cir. 2009) (citing Daubert, 509 U.S. at 589–90).
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CONCLUSION
It is ORDERED that:
1) 	the motion to exclude Kelly’s testimony, Dkt. 49, is:
a) 	GRANTED to the extent it challenges Kelly’s testimony about Crete’s hiring of
Shaffer, Shaffer’s qualifications, whether Crete kept adequate records, and whether
Shaffer was adequately trained; and
b) 	DENIED to the extent it challenges Kelly’s testimony about causation; and
2) 	the motion to exclude Leifer’s testimony, Dkt. 50, is DENIED.
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