May et al v. United States of America

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WO
IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF ARIZONA
Delores May, et al.,
Plaintiffs,
v.
United States of America,
Defendant.
No. CV-23-08120-PCT-JJT
ORDER
At issue are Plaintiffs Delores May and Dominic Tracy’s Motion to Exclude
Opinions/Testimony of Joseph Peles and Brian Onstot (Doc. 95), to which Defendant the
United States filed a response (Doc. 120) and Plaintiffs filed a reply (Doc. 121); Plaintiffs’
Objections to the government’s response (Doc. 122), to which the government filed a
response (Doc. 124); and the government’s Motion to Preclude Plaintiffs’ Accident
Reconstructionist Expert Patrick DeJonghe’s Testimony Pursuant to Daubert (Doc. 96), to
which Plaintiffs filed a response (Doc. 114) and the government filed a reply (Doc. 120,
consolidated with its response).
I. BACKGROUND
On April 13, 2021, Plaintiff Delores May pulled her car out of a scenic overlook in
northern Arizona and onto Interstate 93, when her car was struck by the blade of a bulldozer
being hauled on a tractor-trailer driven by David Roy Holmes, a U.S. Department of Energy
employee, causing injuries to her and her two passengers, Dominic Tracy and J.T., a minor.
(Doc. 18, Am. Compl. ¶¶ 11–15.) She “mistakenly believed she was entering a non-existent
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acceleration lane as she exited the parking lot of the . . . Overlook . . . and drove her SUV
directly into the path of a [Western Area Power Administration] tractor-trailer truck that
was transporting a bulldozer on its flatbed in U.S. 93’s Number 2 outer/slow lane.” (Doc.
97 at 2.)
Plaintiffs initiated this lawsuit on June 30, 2023 (Doc. 1), and they raise a single
claim under the Federal Tort Claims Act (FTCA) premised on driver negligence. The
parties have informed the Court in multiple briefs that Plaintiffs have sued the State of
Arizona in state court for defective road design. (E.g., Docs. 88; 108 (Plaintiffs’ witness
stating that, “[i]n a related state court action, Plaintiffs have sued the State of Arizona,
claiming that it negligently designed US 93 by failing to add an ‘acceleration’ lane for
vehicles to part the scenic overlook.”).) Thus, at issue in this lawsuit is Plaintiffs’
negligence theory “about the driver’s fault, his alleged breach of duty, and the liability it
allegedly triggered in the United States.” (Doc. 119 at 3; Doc. 131, Order.)
To that end, each side has engaged an accident reconstructionist to provide expert
testimony at trial, and now the parties each move to exclude the testimony of the opposing
party’s expert under Daubert and its progeny.
II. LEGAL STANDARD
Under Federal Rule of Evidence 702, an expert may testify on the basis of
“scientific, technical, or other specialized knowledge” if it “will assist the trier of fact to
understand the evidence,” provided the testimony rests on “sufficient facts or data” and
“reliable principles and methods,” and “the witness has reliably applied the principles and
methods to the facts of the case.” Fed. R. Evid. 702(a)–(d). The trial judge acts as the
“gatekeeper” of expert witness testimony by engaging in a two-part analysis. Daubert v.
Merrell Dow Pharms., Inc., 509 U.S. 579, 589, 592 (1993). First, the trial judge must
determine that the proposed expert witness testimony is sufficiently reliable and based on
scientific, technical, or other specialized knowledge. Id.; Kumho Tire Co. v. Carmichael,
526 U.S. 137, 147 (1999). Second, the trial court must ensure that the proposed testimony
is relevant—that it “will assist the trier of fact to understand or determine a fact in issue.”
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Id. “Evidence is relevant if it has any tendency to make a fact more or less probable than it
would be without the evidence and the fact is of consequence in determining the action.”
Fed. R. Evid. 401.
“The inquiry envisioned by Rule 702” is “a flexible one.” Daubert, 509 U.S. at 594.
“The focus . . . must be solely on principles and methodology, not on the conclusions that
they generate.” Id. The advisory committee notes on the 2000 amendments to Rule 702
explain that Rule 702 (as amended in response to Daubert) “is not intended to provide an
excuse for an automatic challenge to the testimony of every expert.” See Kumho Tire, 526
U.S. at 152. “Vigorous 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 595 (citation omitted).
III. ANALYSIS
As a threshold matter, in a case such as the present one that must be tried to the
Court, not a jury, see 28 U.S.C. § 2402, many of the policies underlying Daubert and its
progeny regarding the Court’s role as gatekeeper of expert evidence presented to a jury are
not present, because at trial the Court will be both factfinder and arbiter of the law. As
many of the evidentiary issues raised by the parties in their briefs can be ruled upon by the
Court in a bench trial, the Court need not address them now, outside the trial context. Still,
the Court must determine prior to trial if each side’s proposed expert testimony is
sufficiently relevant and reliable to be presented at trial at all.
In that regard, the Court first finds that both sides’ accident reconstruction experts,
Mr. DeJonghe for Plaintiffs and Mr. Peles for the government, are qualified to opine on the
matters contained in their reports. Both of them are Accredited Traffic Accident
Reconstructionists. (Doc. 95-4 at 2; Doc 95-5 at 60.) The parties do not argue otherwise,
except to the extent Plaintiffs contend that Mr. Peles is not qualified to testify as to restraint
systems, and specifically, to opine as to whether J.T. was wearing a seat belt at the time of
the accident. (Doc. 95 at 9, 17.) But the testimony Plaintiffs argue is beyond Mr. Peles’s
ken—that the seat belt’s latch plate and webbing stop, the friction marks on the seatback,
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and the seat belt’s intertwinement with the wreckage all indicate J.T.’s seat belt was not in
use (Doc. 95 at 9)—is not testimony as to seat belt design so much as it is testimony as to
what happened in the accident, or accident reconstruction. Mr. Peles does not attempt to
testify, for example, how the seat belt could have been designed more effectively for this
type of collision—testimony that would undoubtedly require seat belt design expertise.
Accident reconstruction is Mr. Peles’s expertise (Doc. 95-5 at 60–63), and thus the Court
will not exclude his opinions about whether J.T. was wearing a seat belt based on any lack
of expertise.
The balance of both sides’ arguments against each other’s accident reconstructionist
testimony go to its weight, not admissibility. A Daubert analysis does not have as its goal
for the Court to determine whose expert is right and whose is wrong (or some combination
of the two) before trial. Both experts employ generally the same methodology; it is each
expert’s application of the facts of this case to that methodology that differs, and in
particular their conclusions about the Perception Reaction Time to be applied here.1 (E.g.,
Doc. 95 at 4–18; Doc. 120 at 11–12.) But simply because the experts disagree in the
conclusions they reach does not make either expert’s opinion unreliable or irrelevant. The
Court will hear both experts’ testimony at trial, and each side will have the opportunity to
cross-examine those experts in an attempt to poke holes in their testimony. Indeed, that is
one of the core purposes of trial.
Plaintiffs make the additional argument that Mr. Peles improperly relied on testing
and analysis conducted by his assistant, Brian Onstot, to reach his conclusions, and the
conclusions must therefore be excluded because Mr. Peles did not conduct the testing or
analysis himself and Mr. Onstot was never disclosed as an expert in this case. (Doc. 95 at
11–17.) But as the government points out (Doc. 120 at 3–10), an expert is able to employ
the help of an assistant to conduct research, tests, or analysis in the formulation of the
expert’s opinions so long as the expert verifies the assistant’s work; it is not required that
1 The parties report that Perception Reaction Time is the time a driver should begin to
respond to a “clear stimulus that presents a fairly straightforward event” of concern. (E.g.,
Doc. 95 at 4 n.2, Doc. 96-1 at 4.)
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the assistant be disclosed as an additional expert. See, e.g., Advisory Committee Notes to
1972 enactment of Federal Rule of Evidence 703; Dura Auto. Sys. of Ind., Inc. v. CTS
Corp., 285 F.3d 609, 612–13 (7th Cir. 2002); Pac. Life Ins. Co. v. Bank of N.Y. Mellon,
571 F. Supp. 3d 106, 115 (S.D.N.Y. 2021). For this reason, the Court declines to exclude
Mr. Peles’s conclusions simply because he relied on certain testing and analysis conducted
by Mr. Onstot.
Finally, the Court need not rule on Plaintiffs’ other objections to Mr. Peles’s
testimony (Doc. 122) at this juncture; the Court will rule on any such objections in the
context of Mr. Peles’s testimony in the bench trial.
IT IS THEREFORE ORDERED denying Plaintiffs’ Motion to Exclude
Opinions/Testimony of Joseph Peles and Brian Onstot (Doc. 95), and the United States’
Motion to Preclude Plaintiffs’ Accident Reconstructionist Expert Patrick DeJonghe’s
Testimony Pursuant to Daubert (Doc. 96).
IT IS FURTHER ORDERED overruling as moot Plaintiffs’ Objections to the
Affidavit of Joseph Peles (Doc. 122). Because all pending pre-trial motions are now
resolved, the Court will set a pre-trial status conference by separate Order.
Dated this 16th day of March, 2026.
Honorable John J. Tuchi
United States District Judge
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