Denise D. Farley v. Eric Schultz and Jeana Schultz

IN THE COURT OF APPEALS OF IOWA

No. 24-0674
Filed May 7, 2025

DENISE D. FARLEY,
Plaintiff-Appellant,

vs.

ERIC SCHULTZ and JEANA SCHULTZ,
Defendants-Appellees.
________________________________________________________________

Appeal from the Iowa District Court for Polk County, Scott Rosenberg,

Judge.

Plaintiff appeals the denial of her motion for new trial involving the

inadmissibility of an expert witness. AFFIRMED.

Frederick W. James and Blake Gibney of RSH Legal, P.C., Des Moines, for

appellant.

Stefanie J. Thomas-Nichols of Law Offices of John M. Guthrie, Des Moines,

for appellees.

Considered without oral argument by Greer, P.J., and Langholz and Sandy,

JJ.
2

GREER, Presiding Judge.

Not all cases require experts, especially where a jury can understand the

facts. Here, Denise Farley slipped and fell on ice at Eric and Jeana Schultz’s

property. After Farley instituted a lawsuit, the district court excluded the testimony

of Farley’s expert witness, a mechanical engineer. The jury returned a verdict

finding her to be fifty-one percent at fault, requiring an order for judgment in the

Schultzes’ favor. Farley moved for a new trial asserting the district court abused

its discretion by excluding her expert. The district court agreed with the

Schultzes—the expert’s opinions were either not proper expert testimony or not

properly disclosed—and denied the motion for new trial.

On our review of the denial of the motion for new trial, the opinions solicited

through Farley’s expert did not go to subjects that required any established

expertise, thus, the court did not abuse its discretion in making its evidentiary

ruling, we affirm the jury’s verdict.

I. Factual and Procedural Background.

On January 5, 2021, Farley slipped and fell on ice that accumulated on the

Schultzes’ sidewalk. The fall was captured on the Schultzes’ home security

camera system. As a part of her legal claims against the Schultzes, she alleged

that the Schultzes were negligent in: (1) allowing ice to accumulate on the sidewalk

in front of their home; (2) failing to maintain their premises in a safe condition;

(3) failing to treat their sidewalk when ice was present; (4) failing to re-treat their

sidewalk when ice was present; and (5) failing to warn pedestrians of the

hazardous conditions existing at the time, along with any other acts or omissions

that might become known in discovery. The Schultzes denied the allegations and
3

asserted several affirmative defenses, including a contention that Farley’s fault

should be compared to the fault of other parties, if any.

The parties designated expert witnesses; Farley listed Duane Wolf as an

expert in mechanical engineering who would testify “regarding the fall, the West

Des Moines, Iowa municipal code, [the Schultzes’] non-compliance with the Code

and actions [the Schultzes] could have taken to make their property safe.” The

Schultzes designated Dan Hicks, a member of the American Meteorological

Society to testify about the weather conditions and the Schultzes’ compliance with

“certain West Des Moines city ordinances.” Wolf provided a written report that

listed what he had reviewed to form his opinions. He also addressed the

topography of the area, showing that the Schultzes’ lot sloped from the west to the

east such that any snow accumulated on the west side of the driveway would melt

and flow “across the sidewalk and apron portion of the driveway en route to the

street.” Also included in the report was Wolf’s research of weather data for the

days surrounding the fall, his review of the West Des Moines applicable ordinances

and four opinions, set out as follows:

(1) The source of the ice which initiated the slip and fall which
resulted in the injuries suffered by [Farley] was most likely water from
melted snow along the west side of the driveway which thawed,
flowed across the sidewalk and then froze again following sunset as
temperatures fell in the late afternoon and evening hours on
January 5, 2021.
(2) Based upon the topography of the area in front of [the
Schultzes’ property], moving snow from the driveway to an area east
of the driveway and south of the sidewalk (between the sidewalk and
street) would help to minimize the potential for snow to melt, flow
across the sidewalk and freeze again in the area [where Farley fell].
(3) According to the requirements of [West Des Moines],
property owners are required to remove or maintain snow and ice on
their sidewalks within a reasonable time from when they
accumulated and this time period is not to exceed 24 hours. . . .
4

Because [the Schultzes] were home throughout the day, they would
have had adequate time to apply . . . ice melt, sand or cinders to the
sidewalk area prior to the development of ice on the sidewalk and
prior to [Farley’s fall].[1]
(4) If some form of ice maintenance had been performed on
the sidewalk area prior to [Farley’s fall], the potential for the subject
incident and her subsequent injuries would have been significantly
reduced.

Prior to trial, the Schultzes moved to exclude the opinions offered by Wolf.

The district court reserved ruling until the pretrial motions were heard, but the case

was continued and no one returned to the question until almost a year later, when

trial again was on the horizon. By this time, the Schultzes had deposed Wolf, and

in January 2024, they renewed their motion to exclude his testimony with details

from the March 2023 deposition. Neither party amended or supplemented their

expert disclosures. At the pretrial hearing, the court orally sustained the motion to

exclude Wolf’s expert testimony in full.

During the trial, Farley presented an offer of proof related to Wolf’s

testimony. In that offer, Wolf set out the opinions he would testify to at trial, which

summarized those listed in his written report but also disclosed other opinions

related to the subjects of thermodynamics and heat transfer. Following that offer

of proof, the district court confirmed its earlier ruling, excluding the testimony of

Wolf. After the jury returned its verdict finding Farley to be fifty-one percent at fault,

thus allowing no recovery, Farley moved for a new trial. She asserted that the

exclusion of Wolf’s testimony was an abuse of discretion and prejudiced her. After

the motion for new trial was denied, the court filed a written order noting that the

1 In a ruling addressing the Schultzes’ motion in limine, the court excluded any

testimony related to the West Des Moines ordinances imposing civil liability on
property owners.
5

disclosed opinions did not aid the jury and because Wolf made no specific

calculations and make findings duplicating the weather conditions in testing in the

earlier disclosures, the general additional testimony involving thermodynamics or

heat transfer were later opinions not disclosed.

Farley appeals the denial of her motion for new trial.

II. Scope and Standard of Review.

The standard of review over a ruling on a motion for new trial depends on

the grounds for new trial asserted in the motion and ruled upon by the district court.

Hansen v. Cent. Iowa Hosp. Corp., 686 N.W.2d 476, 480 (Iowa 2004). “If the

motion and the ruling are based on a discretionary ground, we review the ruling for

abuse of discretion.” Id. Such is the case here, when we review for abuse of

discretion over whether a district court properly excluded expert witness testimony.

See Eisenhauer ex rel. T.D. v. Henry Cnty. Health Ctr., 935 N.W.2d 1, 9 (Iowa

2019). “An abuse of discretion occurs when the court exercises its discretion on

grounds or for reasons clearly untenable or to an extent clearly unreasonable.”

Graber v. City of Ankeny, 616 N.W.2d 633, 638 (Iowa 2000) (cleaned up).

“Grounds are untenable when they are unsupported by substantial evidence or

based on an erroneous application of law.” Haskenhoff. v. Homeland Energy

Sols., LLC, 897 N.W.2d 553, 570 (Iowa 2017). Even if a trial court has abused its

discretion, we will only reverse if we are also “convinced that the error materially

affected [Farley’s] substantial rights.” Fry v. Blauvelt, 818 N.W.2d 123, 130 (Iowa

2012); see Iowa R. Civ. P. 1.1004(1) (allowing a new trial if “an abuse of

discretion . . . prevented the movant from having a fair trial”).
6

III. Discussion.

To start with, Iowa courts are “committed to a liberal view on the

admissibility of expert testimony.” See Ranes v. Adams Lab’ys, Inc., 778 N.W.2d

677, 685 (Iowa 2010). And “[a]n opinion is not objectionable just because it

embraces an ultimate issue.” Haskenhoff, 897 N.W.2d at 600 (quoting Iowa R.

Evid. 5.704). Yet the opinion should be “helpful to the jury and bear[] on matters

outside the realm of common knowledge and experience.” See State v. Fox, 480

N.W.2d 897, 899 (Iowa Ct. App. 1991). We recognize the tension that can occur

between the court’s discretionary decision to disallow expert testimony and a

party’s desire to creatively try his or her case.

So, we look to our rules of evidence for guidance on what qualifies as

admissible expert testimony. See Iowa R. Evid. 5.702 (“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 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.”). In Ranes, the test for determining the admissibility of

expert testimony was (1) “if the testimony will assist the trier of fact in

understanding the evidence or to determine a fact in issue (because of the

existence of a reliable body of knowledge, which is also relevant to the issues

being decided by the factfinder)” and (2) “if the witness is qualified to testify as an

expert by knowledge, skill, experience, training, or education.” 778 N.W.2d at 685

(cleaned up). Here, as to the first step, evidence is relevant if “[i]t has any tendency

to make a fact more or less probable than it would be without the evidence” and;

“is of consequence in determining the action.” Iowa R. Evid. 5.401.
7

Because the genesis of this appeal stems from Farley’s assertions in her

motion for new trial, we examine the opinions she believed Wolf should have been

allowed to proffer at trial as set out in her motion. To determine if the court

exercised its discretion on grounds or for reasons clearly untenable or to an extent

clearly unreasonable, we must begin with what opinions were properly disclosed

by Farley and if they would have assisted the jury with its determination of the

facts. Because we can resolve this matter at the first step, we do not have to reach

the expert’s qualifications.2 But, even when an expert’s credentials are sufficient

to qualify him as an expert in relation to the excluded material, that alone is not

enough. See Osborn v. Massey-Ferguson, Inc., 290 N.W.2d 893, 900 (Iowa

1980). In her motion for new trial, Farley set out Wolf’s opinions that the jury should

have been able to consider as:

1. The source of ice upon which [Farley] slipped was
snowmelt from [Schultzes’] property which flowed across the
sidewalk and their driveway and re-froze as temperatures fell in the
late afternoon and early evening.
2. Based upon the topography of the area and moving snow
from the driveway to the east and south of the driveway would help
minimize potential snowmelt across the sidewalk and driveway.
3. [Schultzes] were both working from home that day, did not
leave the residence until that evening, and would have had adequate
time to apply ice melt, sand, or cinders to the sidewalk prior to ice
developing and prior to [Farley’s] fall.
4. Ice formation, at ground level, can and will form when the
actual air temperature is above 32 degrees and how and why this
occurs.

2 Given our liberal standards regarding the testimony of experts, Wolf’s
qualifications as summarized in his deposition and the offer of proof would not have
been the impediment here. The dissent seems to assert that the district court
found Wolf to be unqualified to testify, but we do not read the substance of the
ruling on the motion for new trial in that manner. And, we find there are other more
compelling reasons that justified the district court’s exercise of its discretion here.
8

5. If some form of ice maintenance had been performed on
the sidewalk/[Schultes’] driveway prior to [Farley’s] fall, the potential
for [Farley’s] fall would have been significantly reduced.

In this slip-and-fall case, the jury was instructed that they should resolve

whether the Schultes breached their duty as defined by Iowa Code

section 364.12(2)(b) (2021) (“The abutting property owner [of a public sidewalk] is

responsible for the removal of the natural accumulations of snow and ice from the

sidewalks within a reasonable amount of time and may be liable for damages

caused by the failure of the abutting property owner to use reasonable care in the

removal of the snow or ice.”). From here we ask—would Wolf’s specialized

knowledge allow for opinions that would help the jury understand the evidence or

decide a fact in issue?

Returning to the opinions Farley wanted Wolf to discuss, a video exhibit

clearly showed Farley slipping and falling in the Schutzes’ driveway on what all

agreed was an icy surface. All parties conceded that the sidewalk area where

Farley fell was ice-covered and that it appeared to be from the snowmelt flowing

down the Schultzes’ driveway from the west side of the property where snow had

accumulated on the lawn.3 When subjected to cross-examination during the offer

of proof, Wolf agreed that both parties testified that the ice on the sidewalk area

was from snow melt and that fact was not a “disputed aspect of the case.” In the

second conclusion, Farley wanted Wolf to discuss the lawn and driveway’s

3 Eric Schultz testified that over the fourteen years at the property he was aware

that the snow melt on nice days would cross over the area of the sidewalk and
driveway where Farley fell and that the area was prone to refreezing.
9

topography, but a photograph of the yard was offered as an exhibit, which clearly

showed the snow melt pattern:

And to the assertion that Wolf could have informed the jury that Schultzes could

have shoveled their yard to have minimized the melting/freezing effect across their

driveway, it was certainly a suggestion that would be in the knowledge of a typical

layperson juror. But more to the point, it would not be a duty that was required

under the law the jury was instructed to follow.

The jury was instructed that Farley had to prove Schultzes knew about the

natural accumulation of snow and ice, or that it existed long enough for Schultzes

to have discovered and removed it in the exercise of ordinary care. And as to that

duty to apply ice remediation products, the witnesses, without dispute, confirmed

that the Schultzes were home earlier that day before the fall and that no ice melt

or sand was ever applied to the area where Farley fell that day. Again, without
10

expert testimony, a layperson juror could understand that had ice melt or sand

been applied to an icy area would reduce the risk of a fall. And laypersons certainly

understand how ice melt and sand work on sidewalks. So Wolf’s expert opinions

relating to the ice existing at the time of the fall, the topography of the yard and the

use and benefits of applying ice remediation products were not essential to

understanding these facts. Or as stated another way, the “expert’s scientific,

technical, or other specialized knowledge” on these subjects was not essential to

understanding the facts at issue. See Iowa R. Evid. 5.702.

But here, the jury also had to answer the question if Schultzes had a duty

to apply those ice remediation products before Farley fell, given the law of the

case. No one could testify that when Schultzes left the home before the fall, there

was ice on the area where Farley fell. As to Wolf’s conclusions related to the

thermodynamics of ice formation at ground level during certain temperatures, the

district court reasoned that the expert “performed no experiments or [made] any

attempts to duplicate the weather conditions on the day in question or make any

calculations.” And while one of Wolf’s conclusions suggested that the Schultzes

should have pretreated the sidewalk before any ice formed, that is not a duty

required under Iowa law, even Wolf opined that he could not pinpoint when the ice

formed on the Schultes’ property the day of Farley’s fall.

Instead Wolf’s opinions were cumulative, and thus, the exclusion was not

untenable or unreasonable and, in the end, did not prejudice Farley. Yet Farley

argued:

The other thing with respect to the cumulative point, I think the
testimony is not cumulative. We expect that [Schultzes are] going to
have an expert who’s going to testify about what the air temperature
11

was that evening and that temperatures were above freezing. I think
it’s important for us to be able to offer expert testimony to explain
how it is, in fact, possible that air temperature can be above freezing,
above 32 degrees, while surface area like here, the system that
Mr. Wolf has talked about can, in fact, be freezing and have ice on it.

The Schultzes responded that “difference in air temperature versus ground

temperature” was not in Wolf’s designated opinions and that evidence would not

be relevant because their expert “is simply testifying that at the time that [the

Schultzes] left their home, it is possible that the condition they viewed, wet, was

possible. They left before Ms. Farley crossed the sidewalk.” And in Wolf’s

deposition, he confirmed that he was not providing any opinion as to what time the

water froze by noting, “I have not tried to predict that at this point in my

investigation.” Likewise, Hicks testified that it was “not likely possible to predict

precisely what time meltwater from the snow cover would begin to refreeze on the

Schultzes’ driveway.” “[T]rial courts have a well-recognized role as guardians of

the integrity of expert evidence offered at trials.” Ranes, 778 N.W.2d at 686. “[F]or

the expert’s opinion to be competent, sufficient data must be present upon which

an expert judgment can be made; these facts must be sufficient for the witness to

reach a conclusion which is more than mere conjecture or speculation.” Iowa

Power & Light Co. v. Stortenbecker, 334 N.W.2d 326, 330–31 (Iowa Ct. App.

1983); see also Osborn, 290 N.W.2d at 900. Any testimony offered about when

the snow melt turned to ice on the day of the fall would have involved speculation

and was not competent evidence for the jury’s consideration.

And as for the disclosure of the opinions described in the motion for new

trial, the court stated: “The disclosures regarding [Wolf’s] testimony did not assert

that he would give an expert opinion based upon his knowledge and experience
12

with the laws of thermodynamics and heat transfer. In addition, at the time of his

deposition, Wolf had performed no experiments or ma[d]e any attempts to

duplicate the weather conditions on the day in question or ma[d]e any calculations.

Therefore, the opinions later asserted in the offer of proof were undisclosed to [the

Schultzes].” The written expert disclosure did not contain reference to

thermodynamics or heat transfer. Although, to be fair, some reference was made

in the Wolf’s deposition to these scientific topics, but no defining opinions were

offered at that stage that went towards a fact the jury was to resolve. See McGrew

v. Otoadese, 969 N.W.2d 311, 324 (Iowa 2022) (noting that the expert disclosure

rule involving the summary of facts and opinions “does not require a high level of

specificity, [but] clearly there must be some summary of the actual facts and

opinions to which the witness is expected to testify. A mere list of topics or subject

areas does not meet the requirements of the rule”).

Thus, expert testimony was not required to show there was ice on the

property or that the topography of the property created a situation where melting

snow on the lawn traveled across the sidewalk and driveway. The opinion related

to the topography and effort to minimize the flow of snow melt across the property

was common knowledge based on the testimony of the Schultzes and the

photograph entered as an exhibit. Wolf’s testimony would not have provided any

specialized information a general layperson would not already have known.

Likewise, the expert opinions related to the use of ice melt, sand, or cinders after

discovery of the ice, related to common sense layperson topics and did not require
13

expert testimony.4 Finally, the conclusions involving thermodynamics were

undeveloped and not timely disclosed in a format that would aid the jury in

determining when ice might have formed before the fall.

Based upon the above reasoning, we find that the court’s grounds for

excluding Wolf’s expert testimony were not “clearly untenable or to an extent

unreasonable.” Graber, 616 N.W.2d at 638.

IV. Conclusion.

Finding no abuse of discretion related to the exclusion of the expert

testimony, we affirm the jury verdict rendered.

AFFIRMED.

Langholz, J., concurs; Sandy, J., dissents.

4 In the third disclosed opinion in his first report, Wolf also referenced an obligation

by the Schultzes to pre-apply ice inhibiting measures, but given the law of the case
as found in the jury instructions, that was not a relevant issue and it would have
been improper expert testimony in any event. Also the district court did not allow
testimony about the application of the city ordinances related to snow removal so
those opinions were not relevant.
14

SANDY, Judge (dissenting).

He is a mechanical engineer, and his report really discusses
weather events . . . and whether putting salt or ice down would have
done anything. None of those opinions involve any mechanics . . . .
So I don’t know what a mechanical engineer is offering with respect
to melting and freezing snow when he’s providing no opinion that a
machine could have done anything to change it.

Those words were spoken by defense counsel to the trial court at the final pre-trial

conference in support of its motion to exclude plaintiff’s expert based on relevant

qualifications. The trial court agreed and granted the motion. But a mechanical

engineer is not a mechanic tinkering with machines—he is an expert in physical

science dealing with force and energy. Because the trial court took too narrow a

view of what a mechanical engineer is, it incorrectly excluded Wolf as a plaintiff’s

expert.

In addition, I do not agree with the district court’s conclusion that Wolf’s

opinions were not adequately disclosed through a combination of his report (filed

almost one and a half years prior to trial), his filed affidavit in resistance to the

defendant’s motion to disqualify (filed almost one year prior to trial), and his

deposition (taken almost one year prior to trial). Finally, I disagree with the majority

and district court’s reasoning that Wolf’s trial testimony would only support that

which was already known by the jury: there was ice on the sidewalk. Like the

misunderstanding of the scope of expertise of a mechanical engineer, I find this

reasoning takes too narrow a view of the purpose of the excluded testimony.

Because of these differing views, I respectfully dissent.
15

I. Disclosure.

I disagree that “no defining opinions were offered” at Wolf’s deposition

relative to thermodynamics or heat transfer. An expert is permitted to testify on

matters “within the fair scope of the discovery proceedings.” Milks v. Iowa Oto-

Head Neck Specialists, P.C., 519 N.W.2d 801, 807 (Iowa 1994). In my view, the

following excerpts from Wolf’s deposition (taken eleven months prior to trial)

demonstrate that “defining opinions were offered” relative to “the fair scope of the

discovery proceedings”:

And so I wanted to have some articles in my file that backed up what
I knew to be the phenomenon, the heat transfer phenomenon and
characteristics I believe are involved in this matter.
....
My background on the energy side has been on the thermal side.
Thermal energy is one of six forms of energy. And specifically, I’ve
got extensive background in thermodynamics, which is the study of
heat, temperature, and energy and their relations.
....
Mechanical, again, goes back to the word mechanics, which is the
physical science dealing with force and energy. And if you look at
the interaction between Ms. Farley’s feet and the slick surfaced
posed by the ice, that is force, and that force—the available force or
friction between her shoes and the ice is dictated by friction.5
....
The potential for the subject incident or subsequent injuries would
have been significantly reduced, while ice maintenance would be the
application of some sort of salt or ice-melt compound or the
application of sand or some other friction enhancement material.
....
As I’ve said, I’ve received extensive education in thermodynamics
and heat transfer. Water was far and away the most studied
substance in those classes. So, the thermophysical properties of
water and its performance in various temperatures and conditions, I
have studied extensively as part of my mechanical engineering
background.

5 This answer was specifically explaining his written expert report opinion “[i]f some

form of ice maintenance had been performed on the sidewalk area prior to the
incident involving Ms. Farley, the potential for the subject incident and her
subsequent injuries would have been significantly reduced.”
16

....
Water’s behavior on that sidewalk is going to be a function of the
energy content, which the energy content of that water is going to be
dependent upon what the temperature of the weather conditions are.
....
Well the thing with the weather data is the weather data is ambient
air temperature. But what happens when the sun goes down is that
you can begin to have what’s known as radiative cooling. When the
night sky turns dark, instead of the warm, radiant energy coming from
the sun, an object can now start to radiate energy back into the dark
sky.
....
So in this particular case, when you are two, two and a half hours
past sunset, that the water on the sidewalk can now radiate energy
to the dark sky and potentially freeze even before the air temperature
reaches thirty-two degrees.
....
The salt will dissolve and a thin layer on the top, and the sodium and
chlorine ions separate, and it lowers the vapor pressure of the water,
which reduces the freezing point of the water. The addition of salt to
the surface of the ice, it’s—some descriptions of the event that the
addition of salt creates chaos, or the increase is what we call it in
thermodynamics, the entropy of the system or the water. So, when
you increase that entropy, that lowers the freezing point of the water.
Entropy of water is a thermophysical property that we study in our
thermodynamics classes.

These excerpts coupled with the written expert designation6 clearly place

thermodynamics and heat transfer principles within the “fair scope” of Wolf’s

testimony, as they directly relate to the weather conditions and condition of the

sidewalk where “the fall” occurred as disclosed by Wolf.

But the deposition aside, I find that the written disclosures contained

references to thermodynamics or heat transfer. As a starter, the Iowa Supreme

Court has recognized that so long as the general scope of testimony is designated,

6 The written expert designation stated Wolf would testify about “the fall, the West

Des Moines . . . and actions [the Schultzes] could have taken to make their
property safe.”
17

a line-by-line verbatim transcription of every opinion an expert may give is not

required. Eisenhauer ex rel. T.D. v. Henry Cnty. Health Ctr., 935 N.W.2d 1, 20-21

(Iowa 2019) (finding expert designation stating that the purpose of expert testimony

was to have him testify on issues “standard of care, causation, and damages” and

that his opinions regarding the maneuvers he used in treating the patient were

within the fair scope of his designation); see also Millis v. Hute, 587 N.W.2d 625,

628 (Iowa Ct. App. 1998) (finding that where the plaintiff claimed the defense

expert’s “deposition testimony went beyond the fair scope of the opinions

expressed in his written report,” the purpose of now Iowa Rule of Civil

Procedure 1.508 was “to avoid surprise to litigants and to allow the parties to

formulate their positions on such evidence as is available” and because the

deposition was taken several months before the trial date, the plaintiffs “had

sufficient opportunity to seek further testimony on the disputed issues from their

own experts but chose not [to] do so”).

The question is thus, what is within the “fair scope” of the designation and

whether the defendants were “surprised without sufficient opportunity to seek

further testimony on the disputed issues from their own expert.” Under paragraph

one of the comments section from his expert report, Wolf states that the runoff

“was most likely water from melted snow along the west side of the driveway which

thawed, flowed across the sidewalk, and then froze again following sunset as the

temperatures fell in the late afternoon and early evening hours of January 5, 2021.”

Moreover, he wrote “[i]f some form of ice maintenance had been performed on the

sidewalk area prior to the incident involving Ms. Farley, the potential for the subject

incident and her subsequent injuries would have been significant reduced.”
18

Here, Wolf applied thermodynamic and heat transfer concepts to conclude

the above as further explained in his deposition. Wolf’s opinions need to be read

cumulatively and with common sense given all available materials (his report, his

affidavit, and his deposition). In my view, the exclusion of Wolf’s testimony for lack

of disclosure is inconsistent with case law and too narrowly accounts for all of the

record (his report, his affidavit, and his deposition). It does a disservice to the

process. The fact that Wolf “opined that he could not pinpoint when the ice formed

on the Schultes’ property” does not matter if his expertise nonetheless would have

assisted the jury in determining the window of time within which the ice did form.

All of Wolf’s opinions were within the “fair scope” of the evidentiary disclosures

made to the defendants by way of his report, affidavit, or deposition—all of which

were provided some one year prior to trial.

I am not persuaded that Wolf provided “newly developed opinions.” The

defendants were put on ample notice about what Wolf would testify to and why—

if not by his report and affidavit, certainly by the end of his deposition nearly one

year before trial. And because the defense had their own expert (who had the

benefit of testifying) they had a “fair opportunity to seek further testimony on the

disputed issues.”

II. Qualifications.

Although somewhat lost in translation, the exact motion the defense filed to

disqualify Wolf was based on his lack of qualifications. And that was the exact

motion sustained by the trial court at both the pre-trial conference and the offer of

proof during trial. Iowa Rule of Evidence 5.702 provides that “[a] witness who is

qualified as an expert by knowledge, skill, experience, training, or education may
19

testify in the form of an opinion or otherwise if 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.” Iowa courts generally take a liberal and flexible

approach to the admissibility of expert opinions. Leaf v. Goodyear Tire and Rubber

Co., 590 N.W.2d 525, 533 (Iowa 1999).

Wolf has a bachelor of science and master of science in mechanical

engineering from Iowa State University (ISU) and was formerly a doctor-of-

philosophy candidate in mechanical engineering at ISU. Wolf is a registered

professional engineer in twenty-eight states, including Iowa. He completed

graduate coursework, including some doctorate work, in advanced

thermodynamics subjects, as well as statistics, which focused on building

prediction correlations. During work on his master’s degree, he completed a

research assistantship and taught a thermodynamics course at ISU. His graduate

work emphasis was in thermodynamics and heat transfer area. Since 1995, he

has served as a consultant in slip-and-fall cases in a number of engineering areas,

including moisture control and source analysis. He has conducted seminars and

professional presentations involving weather-related events and their effects on

mechanical systems. He has extensively studied the thermophysical properties of

water and its performance in various temperatures and conditions as part of his

mechanical engineering background.

He has owned his own mechanical engineering consulting firm, Duane A.

Wolf Engineering, located in Ames, Iowa, since 2012. The types of matters he

consults on regularly involve aspects of the weather or weather conditions. He is

a member of the American Society of Mechanical Engineers and a published
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author of several field-related technical papers and industry journal articles. He is

a member of the American Society of Heating, Refrigerating, and Air Conditioning

Engineers, an organization very active in climate-related matters, which sponsors

many seminars and technical sessions at their semi-annual conferences involving

climate related topics. As a licensed professional engineer, he completes thirty

hours of continuing education every two years in which he continues to study

advancements in heat transfer and weather-related information.

Wolf has served on the City of Ames Building Board of Appeals since April

2019. In that role, he has heard appeals involving safety-related issues with

structures in the City of Ames, city ordinances, and the decision-making process.

As a mechanical engineer, he routinely relies on codes, standards, and ordinances

as they pertain to his investigations. Wolf has also served as an expert witness in

over one hundred cases, including those involving slip and falls on sidewalks and

ice. He routinely uses a variety of meteorological and climatological data to

analyze information and form opinions in a wide variety of cases, including slip and

falls. Wolf relies on weather data regularly in his work and is experienced and

knowledgeable about how weather conditions affect surfaces, including residential

sidewalks and driveways. In the present case, the weather or meteorology aspect

that he considered was looking at the temperatures and the weather data during

the relevant time of Farley’s fall. Wolf is also familiar with how ice melt affects the

physical properties of water. His training and education included learning how to

account for how weather conditions affect physical structures and mechanisms,

including residential sidewalks and driveways. He explained during his deposition
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that mechanical engineering plays a role in how snow and ice responds to various

remediation efforts.

He is also familiar with how the topography of an area—including its grade,

slope, and elevation—affects the direction and rate of the flow of water over that

area. In connection with this case Wolf consulted technical papers including topics

covering the effect of salt on freezing point, water vapor data, sand as a friction

coefficient, ice on roadways and surfaces, and nighttime radiative cooling. Basic

concepts within his expertise that are relevant to this case include forces and

friction, fluid mechanics, heat transfer, and city and state ordinances regarding

property maintenance requirements.

Wolf is very qualified. His knowledge, skill, experience, training, and

education qualify him under Iowa case law and evidentiary rules to serve as an

expert witness. While the majority does not take issue with Wolf’s qualifications

but rather whether his opinions would aid the jury in understanding the evidence

or determine a fact in issue,7 in my estimation, the two are inextricably linked. That

is, a full appreciation of his qualifications is key to comprehending how he could

aid the jury in not only understanding the evidence but the fault—which was most

certainly in dispute. Further, while the majority does not question Wolf’s

qualifications, the district court certainly did and it formed the entirety of its

exclusion of him as witness prior to trial commencing. Cognizant that the jury

returned a verdict of forty-nine percent fault to the defendants and fifty-one percent

to the plaintiffs, I next address the relevance of Wolf’s properly disclosed opinions

7 The trial court’s actual pre-trial and offer of proof rulings were not based on “aid

to the jury” reasoning—it was based on Wolf’s qualifications.
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and how disallowance of his relevant opinions to contested issues prejudiced the

plaintiffs.

III. Relevance and Prejudice

I disagree with the majority’s adoption of district court’s reasoning that

“Wolf’s trial testimony would only support that which was already known by the

jury: there was ice on the sidewalk.” (Emphasis added.) In my view, this

oversimplifies Wolf’s testimony, does not give adequate consideration to his

qualifications and expertise as outlined above, and does a disservice to the effect

of the numerous other opinions he would have been able to explain to the jury.

Here is a fair summary of all the properly disclosed opinions of Wolf:

• The weather conditions for the month of January 2021;
• The Schultzes’ specific duty to remove ice from the sidewalk;
• The Schultzes’ specific duty to prevent ice from forming;
• Whether Farley’s slip-and-fall arose from the icy sidewalk;
• How piling snow removed from the driveway in a different location
could have prevented the snowmelt from running onto the sidewalk;
• Adequate time existed for the Schultzes to treat the sidewalk prior
to the Farley’s fall; and
• Preventative measures the Schultzes should have taken would
have significantly reduced the potential for the subject incident.

I cannot read a cold transcript of the trial testimony and summarily conclude that

photographs and self-serving testimony of the Schultzes achieved the same effect

on the jury that an expert with Wolf’s qualifications would have provided.

For example, as to the timing relative to the application of preventative

measures given the climate variables, Wolf opined that since the Schultzes were

both working from home that day and did not leave the residence until that evening,

they would have had adequate time to apply ice melt, sand, or cinders to the

sidewalk prior to ice developing and prior to Farley’s fall. And that if some form of
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ice maintenance had been performed on the sidewalk area prior to Farley’s fall,

the potential for the subject incident would have been significantly reduced.

Establishing a timeline and pinpointing an exact time are distinct. While Wolf may

not have been able to pinpoint the exact minute the ice developed, he did not need

to for the above opinion to help the jury understand the evidence, the general

timeline, or form an opinion as to the following fact at issue—did the Schultzes act

reasonably?

I am not convinced that just because everyone agrees the sidewalk was icy

at the time Farley fell and the snowmelt that caused the ice formation came from

the Schultzes’ property, that Wolf’s testimony would have been cumulative and not

needed to “understand the evidence or determine a fact in issue.” The issue is not

simply whether the sidewalk was icy at the time Farley fell or whether snowmelt

from the Schultzes’ property caused the formation of ice. The issue is whether the

Schultzes were negligent in allowing the icy condition to occur and/or remain.

Wolf’s testimony could have provided the jury valuable expertise making them

capable of more accurately determining whether ice was present on the sidewalk

before the Schultzes left home that evening, that they had ample time and notice

to rectify the situation, how the ice melt and the ice presence on the sidewalk could

have been prevented, and what defendants should have done differently. His

failure to provide the exact minute when the ice formed does not make his

testimony any less helpful to the jury in assisting them in their determination of that

ultimate fact question.

The jury was instructed as follows:
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Wolf certainly had disclosed prior opinions relevant to disputed facts at issue in

this instruction,8 and no photograph or lay testimony would have equaled that

testimony to a scientific degree of certainty.

This is but one example. Wolf concluded not only that the source of the ice

upon which Farley slipped was most likely snowmelt from the Schultzes’ property,

but that based upon the topography of the area, had the piled-up snow from the

driveway been moved to the east and south of the driveway, the potential for

snowmelt to flow across the driveway and sidewalk would have been minimized.

In a case with a two percent differential of fault, such expert testimony was indeed

relevant to the Schultzes’ negligence and exclusion of such was prejudicial to

Farley.

I am not able to proclaim that such testimony would not have changed the

way the jury viewed the allocation of fault in this matter. I do not view Wolf’s

8 Such as: why ice can form on a sidewalk when the ambient air temperature is

above 32 degrees; the principles of heat transfer and thermodynamics and how
they are related to and relevant to the issues in the case; why it is relevant and
related to heat transfer and thermodynamics vis-à-vis shading; lack of direct
sunlight and the night sky; the efficacy of ice-melt; and how ice melt works.
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propounded testimony as merely “cumulative” but rather an application of scientific

principles to objective facts to draw conclusions about the Schultzes’ acts (or

omissions) that caused Farley’s fall. To reason that photographs and lay witness

testimony aided the jury in the same way someone with Wolf’s qualifications would

ignores how a mechanical engineer is able to use his or her expertise in force and

energy in rendering scientific opinions.

Finally, there is one additional matter that I find troubling. The trial court

allowed the Schultzes’ expert, Dan Hicks, to testify. Hicks relied on weather data

to reach his conclusions. Hicks was permitted to opine about whether the sidewalk

was icy or merely “wet” when the Schultzes left the property for the evening but

competing and conflicting expert testimony by Wolf was disallowed. Like Wolf,

Hicks could not ascertain the exact minute that ice had formed. Yet he testified

about the general timeline. I fail to understand how the defense expert was allowed

to testify about the condition of the sidewalk and timing of such condition relative

to the weather when the court had previously ruled that Wolf’s testimony “would

only support that which was already known by the jury: there was ice on the

sidewalk.” (Emphasis added.) If the propounded testimony would truly not aid the

jury, it would not aid the jury for both parties.

Because liability was determined without the benefit of Wolf’s timely

disclosed and relevant testimony on the Schultzes’ negligence and liability, and

because such was critical to Farley’s case and thus prejudiced her, I respectfully

dissent. I would reverse and remand the case back to the district court to be retried

to a jury consistent with the opinions set forth above.