Expert Witness Profiler

Category: Human Factors Expert Witness 

  • Human Factors Expert Was Allowed to Testify About Limits of Visual Perception

    Human Factors Expert Was Allowed to Testify About Limits of Visual Perception

    Plaintiff Judith Bean alleged that this action arose from a February 28, 2023, trip-and-fall incident at Walmart Supercenter Facility #5686, located at 1301 N. Victory Place, Burbank, California, and asserted causes of action for negligence and premises liability.

    Walmart filed a motion in limine to preclude Plaintiff’s expert witnesses, Alex J. Balian and Kuba Glazek, Ph.D., from testifying about certain topics. Plaintiff filed a motion in limine to exclude improper opinions by Walmart’s rebuttal safety expert, Michael V. Nichols.

    Retail Store Expert Witness

    Alex J. Balian has been in the retail industry as an owner, operator, and consultant for more than 65 years.

    He has testified as a safety and operations expert in all areas of retail
    store operations and public facilities involving supermarkets, commercial buildings, restaurants, warehouse facilities, home improvement stores and specialty stores for more than thirty years.

    He has qualified as a retail safety expert and given expert testimony in state and federal courts in matters pertaining to retail operations throughout the United States.

    Want to know more about the challenges Alex Balian has faced? Get the full details with our Challenge Study report.

    Human Factors Expert Witness

    Kuba J. Glazek has a Ph.D. in Brain and Cognitive Sciences. He has researched, published, presented, and consulted on human factors since 2006 and has applied his background in human cognition and scientific methods to analyze a variety of legal cases, including but not limited to premises, transportation, construction, industrial, products, sports, dram shop, and warnings cases.

    Get the full story on challenges to Kuba Glazek’s expert opinions and testimony with an in-depth Challenge Study.

    Safety Expert Witness

    Michael V. Nichols has a Bachelor of Science in Occupational Health & Safety, along with ample experience in retail security and safety. He has been practicing as a Safety Consultant since 1992, conducting safety inspections and consulting on liability and workers’ compensation.

    Nichols also taught Accident Investigation, Cal-OSHA Law, and Workers’ Compensation at Cal State Dominguez Hills University for fifteen (15) years. As a safety expert witness, he has testified over 130 times and given more than 1300 depositions since 1992.

    Discover more cases with Michael Nichols as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Discussion by the Court

    I. Walmart’s MIL No. 4

    First, Walmart argued that Balian, a “retail-safety” expert, cannot offer opinions regarding “human factors” because he has no expertise in that field.

    Second, Walmart argued that Balian cannot offer opinions regarding prior incidents because his deposition testimony shows that he did not study the prior incidents to verify whether they were substantially similar and therefore probative.

    Third, Walmart argued that Balian should be precluded from testifying that Walmart engaged in a “conscious and wanton disregard” for Plaintiff’s safety because he admitted at his deposition that he used the term in a non-legal way.

    Finally, Walmart’s notice of the motion in limine further sought to exclude Plaintiff’s human factors expert, Kuba Glazek, Ph.D., on the ground that his testimony is unnecessary.

    II. Plaintiff’s MIL No. 4

    Plaintiff sought to exclude certain testimony by Walmart’s rebuttal retail safety expert, Michael V. Nichols, on the grounds that his opinions are beyond his designation as a rebuttal expert and/or are inadmissible credibility, advocacy, legal conclusion, and factual determination conclusions that invade the province of the jury or attempt to contradict Walmart’s binding admissions.

    The Court’s Analysis

    The Court found that a considerable amount of the content in Balian’s report, Glazek’s report, and Nichols’ rebuttal report will be inadmissible testimony at trial as improper legal conclusions or determinations that invade the province of the jury.

    Accordingly, the Court will not permit any expert witness for either party to testify as to their conclusions regarding issues for the jury to decide, including: whether the stackbase at issue was “unsafe,” a “trip hazard,” a “dangerous condition,” or below industry safety standards; whether Walmart’s policies and/or training was adequate or met industry standards/a standard of care or whether Walmart employees could have prevented the incident.

    Given that the Court found much of what Walmart objected to in Balian’s report and what Plaintiff objected to in Nichols’ report improper for reasons other than the reasons underlying the motions in limine, the Court need not specifically rule on each of the grounds in the respective motions in limine.

    To the extent that Walmart sought to exclude Glazek from testifying as to human factors on the grounds that his testimony is unnecessary and cumulative, the Court denied Walmart’s motion. Glazek may provide testimony based on his specialized knowledge, such as to limits on visual perception, human behavior, etc., that would be helpful to the jury to interpret the evidence. But Glazek may not interpret the evidence for the jury. To the extent that Plaintiff sought to exclude Nichols’ testimony as outside of the scope of rebuttal, the Court denied Plaintiff’s motion at this time. Plaintiff may raise such an objection to specific testimony at trial.

    Held

    The Court denied Walmart’s fourth motion in limine to preclude certain testimony by Alex Balian and Kuba Glazek as well as Plaintiff’s fourth motion in limine to exclude certain testimony by Michael Nichols.

    Key Takeaway

    To avoid expert witnesses invading the province of the jury, the Court does not permit expert witnesses to interpret the factual evidence in this case. Instead, expert witnesses may testify about industry standards, customs, best practices, and norms, and specialized knowledge relating to relevant topics.

    Expert witnesses may be asked hypothetical questions to elicit expert opinions on the aforementioned topics but may not be asked to make conclusions about the facts or evidence of the instant case, as these are issues for the jury to decide.

    Case Details:

    Case Caption: Judith Bean V. Walmart Inc.
    Docket Number: 2:24cv8871
    Court Name: United States District Court for the Central District of California
    Order Date: May 18, 2026
  • Human Factors Expert Allowed to Opine on Foreseeable Behavior 

    Human Factors Expert Allowed to Opine on Foreseeable Behavior 

    This is a strict products liability and negligence case against Adams, the manufacturer of a plastic Adirondack chair that failed and rendered Ronald Scanlan a quadriplegic.

    The Defendant filed motions to exclude opinions of three of the Plaintiff’s expert witnesses: Russell Dunn, Clifford Tribus and Joellen Gill. The Plaintiff filed a motion to exclude opinions of the Defendant‘s expert witness, Dr. David Jones. 

    Economics Expert Witness

    David DeHaven Jones has over 40 years of experience in Economics and Forensic Economics. He earned his BA from the College of Wooster in 1966, and his MA and Ph.D. from Indiana University in 1968 and 1975, respectively.

    Among other roles, Jones served as a Professor of Economics at the
    University of St. Thomas and as the Director of Policy Analysis at the Minnesota Department of Economic Development. He has authored numerous publications, including “A Note on Life Expectancy and Mortality Adjustment,” Journal of Legal Economics.

    Want to know more about the challenges David DeHaven Jones has faced? Get the full details with our Challenge Study report.

    Chemical Engineering Expert Witness

    Russell Franklin Dunn is a Ph.D. chemical engineer, who has spent his career working in plastics manufacturing and teaching plastics engineering and safety at Vanderbilt University.

    Discover more cases with Russell Dunn as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Spine Surgery Expert Witness

    Clifford Boehe Tribus is a fellowship-trained, board-certified spine surgeon. He is a graduate of Johns Hopkins Medical School. His fellowship training was in spine surgery. He has been a professor of neurosurgery and orthopedics at the University of Wisconsin Medical School for over 30 years.

    Get the full story on challenges to Clifford Tribus’ expert opinions and testimony with an in-depth Challenge Study.

    Human Factors Expert Witness

    Joellen Gill attended Georgia Tech and Wright State Universities for her undergraduate work, earning a BS in human factors engineering in 1979. Her nearly four-decade career includes 15 years in aerospace and national defense industries as a human factors engineer specializing in safety and risk management.

    Gill started part time at ACS in 1994 after completing a master’s degree in engineering, accepted a full-time position in 2005, then, after obtaining certification as a Human Factors Professional, was lead engineer on her first case just a year later. She is also a licensed tribometrist and a Certified Safety Professional.

    Want to know more about the challenges Joellen Gill has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    David Jones

    The Plaintiff sought to exclude Jones’ testimony regarding the “mortality adjustment” and “worklife adjustment” applied to reduce the Plaintiff’s future damages.

    Jones’s worklife adjustment to the Plaintiff’s future earning capacity is improper under Wisconsin law. To calculate the Plaintiff’s lost future earning capacity, the finder of fact must determine how many years the Plaintiff is expected to work and then assess the Plaintiff’s earning capacity for those years. For example, it would not make sense for the jury to determine that the Plaintiff could have worked until age 65, but then to reduce his earning capacity based on the likelihood that he would not be working at age 65. Jones’ “potential earnings loss” table reduced the Plaintiff’s potential earnings in each year based on a probability that the Plaintiff would not be working.

    That necessarily underestimated the Plaintiff’s future earnings in the years that the jury decided the Plaintiff likely would be working. The Court granted the Plaintiff’s motion to exclude evidence of Jones’ worklife expectancy opinions as irrelevant and confusing to the jury.

    The Court also excluded Jones’ “mortality adjustment” opinions for similar reasons. To support an award of future health care expenses under Wisconsin law, (1) there must be expert testimony of permanent injuries, requiring future medical treatment and the incurring of future medical expenses; and (2) an expert must establish the cost of such medical expenses.

    Russell Dunn

    The Defendant contended that Dunn’s opinions are not reliable because he relied solely on testing that ATS performed on the chair. This argument has no merit; an expert is entitled to base his opinion on reports or data generated by another.

    The Defendant next argued that Dunn’s opinions related to risk management lacked sufficient scientific and factual foundation because he relied on two documents when forming these opinions and excluded consideration of the Defendant’s quality assurance standard operating procedures.

    At trial, the Defendant will have the opportunity to cross-examine Dunn regarding the documents he did or did not consider when forming these opinions.

    Next, the Defendant argued that Dunn’s alternative design proposals are not supported by sufficient facts or data or are not the product of reliable principles and methods. However, the Court found that Dunn’s report was sufficient to place the Defendant on notice that the Plaintiff may argue that the addition of antioxidants to the chair’s polymer is a safer alternative design.

    The Defendant argued that Dunn’s opinions on the root cause of the chair’s failure are not reliable because he failed to consider the Plaintiff’s intoxication at the time of the accident. The fact that an alternative explanation or contributing cause existed did not make Dunn’s opinion unreliable.

    The Defendant argued that Dunn’s opinions related to the Defendant not meeting the outdoor furniture industry’s standard of care were not supported by sufficient facts or data. Dunn was entitled to rely on the representative’s sworn testimony to conclude that the Defendant did not test for oxidative degradation. Therefore, the Court cannot conclude Dunn was wrong in relying on the information the Defendant produced in discovery.

    Clifford Tribus

    The Defendant argued that the Court should exclude the Plaintiff’s expert Clifford Tribus because he was not timely disclosed as a principal expert and was improperly designated as a rebuttal expert.

    Tribus’ report rebuts the Defendant’s biomechanical expert’s conclusion that the severity of the injury indicates the Plaintiff must have been in motion when the injury occurred. Tribus was properly designated as a rebuttal expert.

    The Defendant also argued that Tribus’ opinions are not based on sufficient facts or data and are unreliable. Tribus testified that he relied on the Plaintiff’s CT scan and MRI imaging to determine that a low velocity fall could have caused the Plaintiff’s injuries; he did not review any scholarly publications or perform additional research. This is despite the fact Tribus wrote in his report that he had reviewed literature regarding Diffuse Idiopathic Skeletal Hyperostosis (DISH). 

    Moreover, Tribus’ repeated statements that he formed his opinion based on a “generic approach” to DISH injuries does not explain the “methodologies and principles” underlying his opinion in this specific case. Further, though Tribus stated in his opinion that “the literature demonstrates” that DISH patients could suffer severe consequences from slow falls, his testimony reveals that he could not identify any piece of “literature” upon which he relied to form this opinion. That calls into question the reliability of his conclusions. The Court cannot determine if the “literature” on which Tribus relied is sufficient because Tribus does not identify that literature.

    Joellen Gill

    The Defendant contended that Gill is not qualified as a chair designer and cannot opine about the chair’s design.

    Gill never opined about how the Defendant could remedy the alleged hazards of the chair by changing the physical design of the chair. Gill did opine about possible warnings that the Defendant could have used to reduce the risk inherent in the design, using her knowledge of human behavior. But the presence or absence of a warning label has nothing to do with the physical design of the chair. Gill did not opine on chair design, so whether she is qualified to opine on chair design is irrelevant. Because the Defendant provided no other basis for exclusion, the Court denied the Defendant’s motion to exclude with regard to these opinions.

    The Defendant also argued that Gill did not consider any facts outside of the Plaintiff’s counsel’s version of events. 

    Gill’s opinion is that the Plaintiff’s decision to sit on the chair arm was foreseeable human behavior. Gill elaborated in her deposition that her “opinions are focused on were the actions that were engaged in by this person who was injured, were they consistent with foreseeable human behavior. And, in this case, somebody sitting on the arm of a chair to facilitate a conversation is—it was certainly foreseeable behavior.”

    The Plaintiff’s state of mind or motivations—that is, why he chose to sit on the chair arm—are not encompassed in Gill’s opinion about whether the decision to sit on the arm of a chair is foreseeable human behavior. So the Plaintiff’s decision-making process and whether that decision-making process was impaired by his intoxication are not relevant to Gill’s opinion that his actions were consistent with the foreseeable behavior of an outdoor chair user.

    Held

    • The Court granted the Plaintiff’s motion to exclude portions of Dr. David Jones’ opinions. 
    • The Court denied the Defendant’s motion to exclude portions of Dr. Russell Dunn’s opinions. 
    • The Court granted the Defendant’s motion to exclude Dr. Clifford Tribus’ opinions.
    • The Court denied the the Defendant’s motion to exclude Joellen Gill’s opinions. 

    Key Takeaway

    The expert must explain how that experience leads to the conclusions reached, why that experience is a sufficient basis for the opinion, and how that experience is reliably applied to the facts.

    Case Details:

    Case Caption: Scanlan V. Adams Manufacturing Company
    Docket Number: 2:22cv586
    Court Name: United States District Court, Wisconsin Eastern
    Order Date: February 24, 2026
  • Forensic Engineering Expert Not Allowed to Opine on OSHA Violations

    Forensic Engineering Expert Not Allowed to Opine on OSHA Violations

    Olivia Hernandez and her nephew, Hector Ontiveros, Jr., were working at a pillow manufacturing plant owned and operated by Comfort Revolution Manufacturing of Mississippi, LLC, when Olivia was injured by a “molding pillow carousel” manufactured, sold, and installed by Defendant.

    Hector heard a scream while working on the same assembly line as his aunt Olivia’s head was caught in a pinch point at the demolding area after she attempted to remove a pillow that fell from the mold onto the floor. This unfortunately crushed Olivia’s head, but she was eventually removed from the machine. Olivia later succumbed to her injuries at the hospital.

    Defendants designated Dr. Steven R. Arndt as an expert in human factors, requesting that he “assist in the investigation and understanding of the human factors issues associated with the subject incident.” Plaintiffs designated Mark R. Cannon “to perform an analysis and evaluation of the causal factors which allowed Hernandez to become entrapped, and critique and evaluate Cannon’s responsibility as the designer and installer of the production line.”

    Both parties sought to strike and exclude the other party’s expert witness.

    Human Factors Expert Witness 

    Steven Robert Arndt is a human factors scientist with advanced degrees in industrial engineering- human factors specialization (MSIE and PhD) from the University of Wisconsin. Arndt is a consultant with substantial experience in the investigation and prevention of accidents and injuries related to consumer products, warning labels, instructions, training, industrial and occupational settings, and transportation related systems.

    Discover more cases with Steven Arndt as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Forensic Engineering Expert Witness

    Mark Russell Cannon has over 25 years’ experience in forensic engineering and investigates a wide variety of mechanical and safety issues, including workplace injuries involving machinery, machinery failures and consumer product failures.

    Want to know more about the challenges Mark Cannon has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    Mark R. Cannon

    The Court is of the opinion that Cannon’s testimony and opinions should be excluded because his report relied heavily on an incorrect OSHA standard.

    Cannon used the 42-inch guardrail height requirement found in OSHA 1910.29(b)(1) to show “Cannon violated OSHA regulations when they installed the ~34-inch barrier.” He also cited other organizational codes requiring a 42-inch-high railing which have no bearing on the case sub judice.

    The Court found that this information was irrelevant for this case’s purposes, and while Cannon did not rely solely on this information, it is foundational to his entire expert report. Plaintiffs argued that Cannon “opined and testified that the standard shows the logic behind a 42-inch height as opposed to the 34-inch height utilized by Cannon USA in its design” and “his opinions were not asserting that the design was unsafe or unreasonably dangerous solely because of an alleged violation or failure to comply with the OSHA standard” These arguments are unconvincing because at several instances, Cannon’s report reads, “[Defendant] violated OSHA regulations.”

    Steven R. Arndt

    Defendant claimed that Arndt’s opinions were necessary to combat the mischaracterization of safety codes put forth by Plaintiffs’ expert, Cannon, and that his testimony was essential to refute Plaintiffs’ expert’s erroneous interpretation of code and regulatory requirements. While the Court took issue with this characterization of Arndt’s testimony, it would not upset a party’s reason for proffering an expert witness.

    Therefore, because Cannon was excluded—along with the testimony Defendants specifically claimed they were using Arndt to combat—the Court struck Arndt’s testimony and opinions regarding any rebuttal against Cannon for the purpose of trial. More specifically, the Court struck the “Rebuttal” section of his expert report and any testimonial reference to it. Additionally, the Court did not permit Arndt to testify to conclusions of law or tell the jury what conclusion it should reach in this matter.

    Held

    • The Court granted in part and denied in part Plaintiffs’ Daubert motion to exclude or limit the testimony of Steven Arndt.
    • The Court granted Defendant’s motion seeking to exclude Plaintiffs’ expert Mark Cannon.

    Key Takeaway

    An expert may never render “conclusions of law,” opine “on legal issues,” or “tell the jury what result to reach.”

    Case Details:

    Case Caption: Nolazco V. Cannon USA, Inc.
    Docket Number: 1:24cv12
    Court Name: United States District Court, Mississippi Northern
    Order Date: March 16, 2026
  • Human Factors Expert Not Allowed to Opine on the Tile

    Human Factors Expert Not Allowed to Opine on the Tile

    Plaintiff Rebecca Bell alleged that she fell while an invitee at the Hobby Lobby store in Daphne, Alabama.

    She filed suit against Hobby Lobby Stores, Inc. and Alex Mendoza (manager of the Daphne Hobby Lobby store) asserting causes of action for negligence, wantonness, and negligent/wanton hiring, training, supervision or retention.

    Plaintiff stepped on an uneven tile while shopping inside the Hobby Lobby store in Daphne, Alabama. She argued that the uneven floor tile caused her to fall. Plaintiff did not trip or slip. Rather, Plaintiff alleges she stepped “half on good tile, half on bad tile,” causing her foot to roll. The depression in the subject tile was not greater than 1/4″.

    Plaintiff proffered the testimony of Dr. Ian Noy and an affidavit of John Shepherd. Both Noy and Shepherd opined that the subject tile constituted a hazardous condition. Defendants filed a motion to exclude Noy’s testimony and argued that Shepherd’s affidavit should be disregarded as conclusory.

    Human Factors Expert Witness

    Ian Yechiam Noy is immensely qualified as an expert in Human Factors and Ergonomics. He is a distinguished Human Factors and Ergonomics consultant and forensic expert with extensive background in innovative and applied safety research, industrial engineering, behavioral sciences, and science management.

    Want to know more about the challenges Ian Noy has faced? Get the full details with our Challenge Study report.

    Retail Store Expert Witness

    John R. Shepherd has worked 40 years in the retail store industry, with 20 years at Walmart and 21 years at Delchamps grocery stores. 

    Throughout his experience in the retail store industry, he was directly involved in developing and implementing policies and procedures relating to floor safety, customer safety and injury prevention.

    Discover more cases with John Shepherd as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Discussion by the Court

    Ian Noy

    Plaintiff retained Noy “to opine on the human factors contributions” to her injuries. Noy opined that the tile was a hazard “because it violated the industry best practice standard set forth in ASTM F-1637.” Noy’s opinion is tied to that standard. The standard mandates walkways be maintained as “flush and even to the extent possible.”

    Noy acknowledged that if a walkway is “as flush and even as possible,” the standard allows for up to a one quarter inch (1/4″) change in elevation. It is undisputed the subject walkway had no variation in elevation greater than a 1/4″. However, Noy contended the subject tile nevertheless violated the standard because the 1/4″ allowance applies only if the walkway is as “flush and even to the extent possible.” Noy opines the subject tile was not as “flush and even to the extent possible,” and therefore should have been “repaired.”

    Noy acknowledged that “flush and even to the extent possible” is a structural determination. He testified, “if it’s physically possible to make the floor flush and even, it should be done. If there was any structural or functional reason why there needs to be a change in elevation, then it has to be as small as possible.” However, Noy is not proffered as a structural expert. Furthermore, he never visited the Hobby Lobby store where Plaintiff fell. He has no knowledge of the construction of the floor or its substrate. He does not know what caused the depression in the subject tile, or when or how it developed. His opinion, though, that the floor should have been “repaired” and that the 1/4″ depression allowance is inapplicable is based on his belief that the floor was not “flush and even to the extent possible.” This belief is mere unsupported “ipse dixit.”

    The Court held that Noy is unqualified to opine that the floor was not “flush and even to the extent possible.” Therefore, he cannot opine the standard 1/4″ depression allowance is inapplicable. Noy’s opinion that “the depressed surface was a foreseeable hazard because it violated the industry best practice standard set forth in ASTM F-1637” is not permissible.

    John Shepherd

    Plaintiff also offered an affidavit of John Shepherd as evidence that the tile constituted a hazardous condition. Defendants argued that Shepherd’s affidavit is “conclusory” and cannot defeat summary judgment. The Court agreed, and found that Shepherd’s opinion suffered the same fatal defects as Noy’s. Shepherd would opine that the “uneven surface in the floor constitutes a fall hazard,” and that “not only should the tile be replaced but underneath the tile should have been replaced.”

    Like Noy, Shepherd is not proffered as a structural expert. He has experience relating to “floor safety, customer safety, and injury prevention.” However, he has no construction or structural expertise or experience. Neither did the record indicate he ever visited the Hobby Lobby store where Plaintiff fell. He had no knowledge of the construction of the floor or its “underneath” substrate, or whether or how it might be “replaced.” He has no knowledge of what caused the depression, or when or how it developed.

    The Court concluded that Shepherd is unqualified to opine the subject tile or its “underneath” should have been replaced. That, and his opinion the “uneven surface in the floor . . . constitutes a fall hazard” are mere conclusory statements that cannot satisfy Plaintiff’s burden to produce sufficient evidence of an “unreasonably” dangerous condition or hazard under Alabama law. His conclusory opinion is not based on any methodology.

    Held

    The Court granted Defendants’ motions to exclude the testimony of Dr. Ian Noy and John Shepherd.

    Key Takeaway

    Nothing in either Daubert or the Federal Rules of Evidence requires a district court to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert.

    Case Details:

    Case Caption: Bell V. Hobby Lobby Stores, Inc.
    Docket Number: 1:24cv422
    Court Name: United States District Court, Alabama Southern
    Order Date: April 17, 2026
  • Human Factors Expert Not Allowed to Opine on Warning Cues

    Human Factors Expert Not Allowed to Opine on Warning Cues

    This dispute arises from the death of 88-year-old Ronald Fronckowiak (the “Decedent”) by carbon monoxide toxicity. Specifically, on the evening of February 22, 2022, Rebecca Jaeger, age 72, drove the Decedent in his 2017 Kia Sorento from the hospital-where he was being treated for a dislocated shoulder and confusion-to the couple’s rental home in Spring Hill, Florida.

    Jaeger exited the vehicle, assisted the Decedent out of the vehicle, and they both proceeded inside with the key fob, which was ultimately left on the kitchen table. Tragically, they left the car running in the enclosed single-car garage.

    The next morning, officers from the Hernando County Sheriff’s Office performed a wellness check on the couple after the Decedent’s family had not made contact with him. Decedent was found deceased in the room next to the garage, and it was later determined that he died from carbon monoxide toxicity.

    The 2017 Kia Sorento is designed with keyless ignition technology, but does not include an automatic shutoff feature. More broadly, 83% of 2017 model year vehicles were found to not offer an automatic shutoff feature, and 91% did not include this as a standard feature.

    Defendant Kia America, Inc. filed a motion to exclude the testimony of Plaintiffs’ expert witnesses Peter A. Hancock and David J. Bizzak.

    Human Factors Expert Witness 

    Peter Adrian Hancock has served as a past president of the Human Factors and Ergonomics Society and other professional organizations. His work includes decades of research, publication, and application of HF/E principles to real-world systems, including transportation systems and human interaction with vehicle technologies.

    Get the full story on challenges to Peter Hancock’s expert opinions and testimony with an in-depth Challenge Study.

    Mechanical Engineering Expert Witness

    David John Bizzak is a Professional Engineer (P.E.) and holds a Ph.D. in Mechanical Engineering. Furthermore, he is also a Certified Fire and Explosion Investigator (C.F.E.I.) and Certified Vehicle Fire Investigator (C.V.F.I.). Bizzak has decades of experience investigating and analyzing automotive systems and other product designs for safety hazards, defects, and failure modes.

    Want to know more about the challenges David Bizzak has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    Peter Hancock

    According to Hancock, the vehicle appeared to have provided insufficient cues as to its continuing, activated status. However, the Court held that such opinions are not directly relevant to the design defect analysis at hand.

    Hancock also opined that there was an “absence of effective, explicitly designed status warning cues.” This opinion, however, is conclusory and unsupported by any articulable methodology.

    David Bizzak

    Similarly, although Bizzak provided more relevant opinions in his report, these do not necessarily signify that the vehicle failed to perform as safely as expected or was unreasonably dangerous.

    According to Bizzak, the subject Kia Sorento was defective by virtue of the fact that it was not equipped with features necessary to guard against carbon monoxide poisoning resulting from an operator inadvertently failing to turn off the ignition before exiting the vehicle.

    However, the Court concluded that the key opinion provided in Bizzak’s report that addressed the alleged design defect was conclusory, as no discernable methodology was provided.

    Held

    Accordingly, the Court granted-in-part Defendant Kia’s motion to exclude the testimony of Peter A. Hancock and David J. Bizzak.

    Key Takeaway

    Importantly, neither Daubert nor Federal Rule of Evidence 702 requires a trial judge to admit opinion evidence that is connected to existing data only by the ipse dixit of the expert. Instead, the judge is free to conclude that there is simply too great an analytical gap between the data and the opinion proffered.

    Case Details:

    Case Caption: Fronckowiak V. Kia America, Inc.
    Docket Number: 8:24cv863
    Court Name: United States District Court, Florida Middle
    Order Date: April 15, 2026
  • Accident Reconstruction Expert’s Testimony on Design Defects Excluded

    Accident Reconstruction Expert’s Testimony on Design Defects Excluded

    This case arises from a single, momentary sideswipe on Interstate 95 in which the rightfront tire of the U-Haul truck driven by Corey Hayes-Goode contacted the left-rear corner of Rigoberto Lagunas-Antunez’s GMC van.

     U-Haul filed certain motions challenging the testimony of Plaintiffs’ experts, Ruston Hunt, Daniel Wolfe, Steven Kean and Brooks Rugemer.

    The Court dismissed Plaintiffs’ claims against U-Haul that were brought under a design defect theory (the “design defect claims”), but denied the motion as to Plaintiffs’ claims against U-Haul under a failure-to-warn theory, as well as to the Estate of Rigoberto’s wrongful death claim against U-Haul. All of Plaintiffs’ claims against Defendant Hayes-Goode remained.

    Human Factors Expert Witness

    Ruston M. Hunt holds a B.S. and M.S. in Industrial Engineering and a Ph.D. in Mechanical Engineering from the University of Illinois, where he also taught and conducted applied research on human error and electro-mechanical systems. With over 40 years of experience in human factors engineering, he has led extensive research and development projects for major government
    agencies and Fortune 500 companies, focusing on operator support systems and human-system interfaces. Hunt has served as a faculty member and administrator at leading institutions, where he taught and developed programs in human factors and systems engineering.

    Fortify your strategy by reviewing a Challenge Study detailing grounds for excluding Ruston Hunt’s expert testimony.

    Accident Reconstruction Expert Witnesses

    Daniel M. Wolfe has a Bachelor of Science Degree in Engineering and a Doctor of Philosophy degree in Electrical and Electrical and Computer Engineering.

    He is a member of the Society of Automotive Engineers, the National Association of Accident Reconstruction Experts, and the Optical Society of America. He is certified by the Society of Automotive Engineers to access and interpret Heavy Vehicle Event Data Recorders in commercial vehicles and is certified as a BOSCH Crash Data Retrieval technician.

    Discover more cases with Daniel Wolfe as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Steven T. Kean has over 25 years of experience in traffic crash investigation and reconstruction, including more than 1,000 crash investigations. He has served as an Accident Reconstruction Team member since 2001 and as Team Leader since 2008, and he holds full accreditation as a Traffic Accident Reconstructionist from ACTAR.

    Kean’s extensive specialized training—spanning advanced crash reconstruction, event data recorder analysis, heavy vehicle investigations, and human factors—demonstrates his comprehensive expertise in evaluating vehicle dynamics and driver behavior. He has been qualified and testified as an expert in multiple state courts, taught advanced crash reconstruction courses to law enforcement and legal professionals, and is an active member of leading professional organizations, including the National Association of Professional Accident Reconstruction Specialists and the Society of Automotive Engineers.

    Get the full story on challenges to Steven Kean’s expert opinions and testimony with an in-depth Challenge Study.

    Trucking Expert Witness

    Brooks Rugemer has over 30 years of experience in trucking safety, driver training, risk management, and accident investigation, including 12 years as a tractor-trailer operator with 1.4 million accident-free miles. He has hired and trained over 5,000 CDL drivers and is intimately familiar with FMCSRs, OSHA regulations, and accepted transportation safety practices.

    Want to know more about the challenges Brooks Rugemer has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    A. Motion to Exclude Expert Ruston Hunt

    U-Haul provided that Hunt opined as to the location of the van relative to the Subject Truck at the time of the accident, that the Subject Truck was defective and unreasonably dangerous due to lacking certain technologies, and that U-Haul allegedly failed to provide adequate warnings and training to inexperienced renters.

    On review of Hunt’s voluminous report, these opinions primarily involve (1) the Subject Truck being unreasonably dangerous and defective because “insufficient warnings and instructions were provided to renters” and because “it lacked a blind spot detection and warning system,” (2) the dangers of failing to “explicitly train” renters on the proper adjustment of the Subject Truck’s side view mirrors; and (3) the accident-prevention effect that blind-spot detection technologies “likely” would have had in this case, had they been installed on the Subject Truck.

    Because Plaintiffs’ design defect claims are no longer viable, Hunt’s opinions that the Subject Truck was defective and unreasonably dangerous due to an alleged design defect are not relevant.

    B. Motion to Exclude Expert Daniel Wolfe

    Wolfe testified as to the Subject Truck’s alleged design defects and alternative technologies that allegedly could have prevented the instant accident.

    As the proposed design-engineering expert, Wolfe’s testimony is relevant only with regard to the now-dismissed design defect claims. Therefore, pursuant to Federal Rule of Evidence 401, the Court granted U-Haul’s motion to exclude the testimony of expert Wolfe.

    C. Motion to Exclude Expert Steven Kean

    U-Haul took issue with two specific opinions proffered by Kean in his deposition: Plaintiffs’ van was in the Subject Truck’s blind spot prior to the accident, and the van was traveling faster than the Subject Truck at impact.

    According to Plaintiffs, Kean’s testimony will “offer critical insight that will help the jury understand the sequence of events and the physical evidence underlying this collision.”

    Because the Court can foresee the potential relevance of an accident reconstructionist’s testimony to Plaintiffs’ remaining claims, the Court denied without prejudice U-Haul’s motion to exclude the testimony of expert Steven Kean at this juncture, subject to a Daubert hearing at the appropriate time in the proceedings to ascertain the reliability of his proffered testimony.

    D. Motion to Exclude Expert Brooks Rugemer

    U-Haul provided that Rugemer’s testimony concerned the countermeasures that U-Haul should have taken in order to prevent the instant accident, such as giving additional training and safety information to inexperienced drivers of rental trucks.

    According to Plaintiffs, Rugemer will “explain to the jury how commercial transportation companies manage blind spot and mirror adjustment risks, what reasonable industry practices exist to mitigate foreseeable lane-change collisions, and how U-Haul’s rental procedures fell short of those well-established standards.”

    Because the Court can foresee the potential relevance of a commercial safety expert’s testimony to Plaintiffs’ remaining claims, the Court denied without prejudice U-Haul’s motion to exclude the testimony of expert Brooks Rugemer at this juncture, subject to a Daubert hearing at the appropriate time in the proceedings to ascertain the reliability of his proffered testimony.

    Held

    • The Court granted U-Haul’s motions to exclude the testimony of Ruston Hunt and Daniel Wolfe.
    • The Court denied without prejudice U-Haul’s motions to exclude the testimony of Steven Kean and Brooks Rugemer.

    Key Takeaway

    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.

    Case Details:

    Case Caption: Lagunas-Antunez V. Hayes-Goode
    Docket Number: 2:24cv416
    Court Name: United States District Court, Virginia Eastern
    Order Date: February 26, 2026
  • Engineering Expert Barred From Opining on the Sidewalk Condition 

    Engineering Expert Barred From Opining on the Sidewalk Condition 

    In this facially simple premises liability lawsuit, Plaintiff Stephanie Lewis sought to recover damages incurred when she tripped and fell on the front walkway of Samuel B. Heggie, Jr.’s home while she was delivering a pizza in February 2020. Samuel Heggie having died during the pendency of this lawsuit, the Plaintiff now proceeds against the Estate of Samuel B. Heggie, Jr., represented by Patrick Heggie as the Administrator ad Litem.

    Plaintiff filed a motion in limine to exclude the testimony of Defendant’s liability expert, Brian Grieser, while the Defendant filed a motion in limine to exclude the testimony of Plaintiff’s expert, David Johnson.

    Engineering Expert Witness

    David Patrick Johnson P.E., CSP is a Licensed Professional Engineer in the State of Tennessee and a Certified Safety Professional. He has over 32 years of experience in safety engineering, including work involving walkway safety and sidewalks.

    Want to know more about the challenges David Johnson has faced? Get the full details with our Challenge Study report.

    Human Factors Expert Witness

    Brian C. Grieser P.E., C.P.S.M., CSP, CPE has extensive experience in conducting evaluations in a wide range of product, occupational, and premises projects involving litigation as well as proactive consulting. His assessments have included walkway slip resistance; recreational boat design; watercraft occupant safety; towed watersports safety; time and motion studies; work sampling; human vibration and acceleration exposure; sound measurement and analysis; and human movement, climbing, and stability analysis.

    Grieser is a member of several professional societies including the Human Factors and Ergonomics Society, ASTM International, the Society of Naval Architects and Marine Engineers, the American Boat and Yacht Council, and USA Water Ski & Wake Sports.

    Discover more cases with Brian Grieser as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Discussion by the Court

    It is undisputed that the Plaintiff tripped on a vertical displacement—i.e., a raised lip—of approximately 0.8 inches in the front walkway leading from Heggie’s driveway to the front door of Heggie’s house. It is also undisputed that Heggie was aware of the condition of the front walkway. The parties dispute whether the defect in the walkway (or sidewalk, as the parties refer to it) created an unreasonably dangerous condition.

    David Johnson

    A. The Parties’ Arguments

    Johnson opined that the pedestrian falls on sidewalks are often the result of the failure of the property owner or other responsible person to maintain the sidewalk in a reasonably safe condition. According to Johnson, if cracks in sidewalks are greater than 1/4 inch, this can create a trip hazard because it is unexpected; if such variances are found, repairs should be made.

    Johnson concluded that the walkway would be considered substandard and hazardous by ANSI and ASTM standards.

    The Defendant characterized Johnson’s opinions as largely concerning matters of common sense dressed up with technical language, or “common experience gilded by the expert’s credentials.” As for reliability, the Defendant contended that (1) many of Johnson’s opinions consisted of verbatim quotations from insurance company websites that Johnson found doing a Google internet search that Johnson himself characterized as “doing some research on some different aspects of trip-and-fall cases” and (2) Johnson’s references to various “safety standards” and “codes” are unreliable, insofar as he admits that none of the standards he cites apply to single-family residences, and none has been adopted by any Tennessee court or Sumner County authority.

    In response, the Plaintiff argued that Tennessee courts have held that whether a sidewalk is unsafe can be established by expert testimony.

    B. Discussion

    1. Relevance

    Several of Johnson’s opinions are based on the failure of the walkway to meet various international standards and codes, including (1) the International Residential Code (“IRC”), which incorporates by reference the International Property Maintenance Code and had been adopted by Sumner County at the time of the incident; (2) the American Standards for Testing and Materials (ASTM) F 1637-2013 Standard Practice for Safe Walking; (3) the American National Standard Institute (“ANSI”) standard 1264.2-2006; (4) standards promulgated by the National Institute of Occupational Safety and Health (“NIOSH”); and (5) the International Code Council (ICC)/ANSI A117.1-2017-American National Standard for Accessible and Usable Buildings and Facilities.

    In his deposition, Johnson conceded that the ANSI and NIOSH standards apply to workplaces, not residences. The ICC/ANSI standards to which he refers pertain to accommodations for persons with disabilities. These standards are irrelevant in this case, which involves a private residence, and Johnson’s reliance on them is misplaced and, moreover, will not assist the jury in determining whether the Defendant was negligent.

    The Plaintiff contended that the IRC code has been adopted by Sumner County and so is clearly applicable. However, the standard contains nothing outside what the common law negligence standard of care establishes. An expert is not required to establish the common law negligence standard.

    Finally, regarding the ASTM F 1637-2013 Standard Practice for Safe Walking, the plaintiff argues that the question of whether this standard has been adopted by Sumner County is irrelevant, because it is a national standard and provides a relevant guide for determining the reasonableness of the Defendant’s conduct in failing to repair the walkway. However, this is not a negligence per se case. The Court finds that this standard, too, is irrelevant to the question of whether the Defendant in this case exercised reasonable care.

    2. Reliability

    The Court found that Johnson’s opinions as a whole will not assist the jury in determining any fact at issue in this case. Moreover, insofar as he appears to have derived many of his opinions directly from insurance company websites, from which he quotes verbatim, and from a manual drafted by a lawyer and intended as litigation support in premises liability cases, those opinions did not rest on a reliable foundation.

    The Plaintiff simply has not established that Johnson’s proposed opinions are the “product of reliable principles and methods” or that they “reflect a reliable application of the principles and methods to the facts of the case.”

    Brian Grieser

    The Defendant sought to offer the expert opinions of Brian Grieser, a consultant with Applied Safety + Ergonomics, a Rimkus Company, to rebut the testimony of the Plaintiff’s expert. He sought to offer the following opinions:

    • As Lewis approached the area of her fall, the subject condition would have been in her field of view and available to be seen.
    • Because of the contrast in color, texture, and depth related to the section of the concrete sidewalk that had settled, the subject condition would have been conspicuous and detectable against the neighboring unsettled concrete.
    • From a human factors perspective, it is reasonable to expect that a pedestrian will encounter pavement conditions that will need to be attended to during normal everyday walking.
    • Immediately prior to the incident, Lewis did not give sufficient attention to where she was walking, which contributed to her incident.
    • Had Lewis paid sufficient attention to the area where she was walking as she approached the settled pavement, she could have changed her gait or path to avoid tripping and falling on the subject condition.
    • Given that the subject condition would have been conspicuous and was a common condition, no additional warning was needed to inform Lewis of its presence.
    • Johnson’s opinions conflict with published research related to pedestrians successfully navigating sidewalks outdoors with elevation changes substantially greater than 1/4-inch.
    • Johnson cited several standards in his report that were not applicable to the subject property and were unlikely to have been known by a homeowner such as Heggie.
    • Johnson did not provide a basis in his report to indicate that the subject condition was a recognized hazard to a typical homeowner.

    Analysis

    Having already found that Johnson’s opinions will not assist the trier of fact, the Court found that Grieser’s first six opinions are excludable for the same reason. 

    These opinions offer nothing that a reasonable jury could not determine on its own without the assistance of expert testimony. The rest of the opinions, the sole purpose of which is to rebut Johnson’s testimony, are unnecessary, as the Court has determined that Johnson will not be permitted to testify.

    Held

    The Court excluded the testimony of both the Plaintiff’s proposed expert, David Johnson, and the Defendant’s proposed expert, Brian Grieser.

    Key Takeaway

    As set forth above, under Daubert, courts assess the reliability of scientific testimony by considering such factors as (1) whether the [expert’s] theory or methodology has been or can be tested; (2) whether it has been subjected to peer review; (3) whether it has a known or potential rate of error; and (4) whether it has been generally accepted in the scientific community. None of these showings has been made here.

    Case Details:

    Case Caption: Lewis V. Heggie, Jr.
    Docket Number: 3:24cv501
    Court Name: United States District Court, Tennessee Middle
    Order Date: December 30, 2025
  • Human Factors Expert’s Testimony on Shopping Cart Maintenance Admitted

    Human Factors Expert’s Testimony on Shopping Cart Maintenance Admitted

    This case arises from the injuries sustained by Plaintiff, Jessica Loseke, and her husband while they were shopping at Menards in Omaha, Nebraska. They were loading a “refurbished cart” with bags of water softener when the cart broke and injured Loseke’s knee.

    Loseke filed a motion in limine to preclude the testimony of Defendant’s expert witness, Alex J. Balian, from being admitted at trial. Defendant, Menard, Inc., a Wisconsin Corporation (“Menards”), filed a motion in limine to exclude the testimony of Plaintiff’s expert William N. Nelson, BSME, MS, MBA, and any other evidence of and/or reference to Nelson’s opinions.

    Retail Store Expert Witness

    Alex J. Balian has been in the retail industry as an owner, operator, and consultant for more than 65 years.

    He has testified as a safety and operations expert in all areas of retail
    store operations and public facilities involving supermarkets, commercial buildings, restaurants, warehouse facilities, home improvement stores and specialty stores for more than thirty years.

    He has qualified as a retail safety expert and given expert testimony in state and federal courts in matters pertaining to retail operations throughout the United States.

    Want to know more about the challenges Alex Balian has faced? Get the full details with our Challenge Study report.

    Human Factors Expert Witness

    William N. Nelson has over 20 years of experience in the application of Biomechanics, Ergonomics, Human Factors and Product Development. His consulting experience is very broad: from industrial to sports; from federal government to private enterprise; from medical institutions to aerospace.

    Nelson’s past work has involved customized training for injury prevention; ergonomic job analysis resulting in a rotation schedule which utilized biomechanical, physiological and skill level data; human factors analysis of Cumulative Trauma Disorder in production processes; development of workstation set up and design.

    Get the full story on challenges to William Nelson’s expert opinions and testimony with an in-depth Challenge Study.

    Discussion by the Court

    Opinions of Alex Balian

    Plaintiff argued that Balian’s proffered testimony is not reliable. Plaintiff stated that “Balian’s opinions are primarily based on his personal experience in the retail industry, rather than on any scientific or technical methodology. His report lacks any empirical data or testing to support his conclusions regarding the safety of Menards’ shopping cart inspection procedures.”

    Opinions of William Nelson

    Defendant argued that “Nelson’s opinions are unreliable. He believed that Menards should have some sort of “preventative maintenance” program, and that Menards should hire employees who are trained in welding to inspect carts. These opinions are not based on any retail-industry specific standards but rather drawn based on his own belief.”

    Analysis

    The Court has carefully reviewed the argument of the parties as well as the briefs, the evidence presented, and in particular, the opinions of both Nelson and Balian.

    Nelson is an engineer who has a working knowledge of welding requirements, and Nelson applied engineering principles from his educational background, studies, and work experience. With regard to Balian, the Court likewise found his testimony relevant and of assistance to the trier of fact in this case. Balian has served as a consultant for retail store operations, where he has advised, trained, and executed policies and procedures in supermarkets and other public facilities.

    Held

    • The Court denied Plaintiff’s motion in limine to preclude the testimony of Alex Balian.
    • The Court denied Defendant’s motion in limine to exclude the testimony of William Nelson.

    Key Takeaway:

    Both experts appeared to have the educational knowledge, training and experience to testify in this case. Their testimony appeared to be such as would assist the trier of fact without invading the province of the jury.

    Case Details:

    Case Caption: Loseke V. Menard, Inc.
    Docket Number: 8:23cv537
    Court Name: United States District Court, Nebraska
    Order Date: November 19, 2025
  • Mechanical Engineering Expert Barred From Testifying for Not Testing Alternative Design

    Mechanical Engineering Expert Barred From Testifying for Not Testing Alternative Design

    Plaintiff Paul Johnson sustained severe injuries while operating a RIDGID K-6200 drain cleaning machine (“subject machine”) at his workplace. He sued the machine manufacturer, Defendant Ridge Tool Company (incorrectly identified as Ridge Tool Manufacturing Company, Inc.), asserting claims for negligence, product liability, and failure to warn.

    Plaintiff brought this lawsuit contending that Defendant manufactured an unreasonably dangerous and defective machine without an appropriate fixed guard that would have prevented Plaintiff from having to hold a rotating cable in his hand that could suddenly twist and kink and pull him. Plaintiff also challenged the adequacy of Defendant’s warnings and argued that personal protective equipment (PPE) was insufficient to protect users from the known hazards associated with this type of drain cleaning machine.

    In support of his claims, Plaintiff relied on two experts, Chad E. Jones, a mechanical engineer, and Cynthia M. Rando, a certified human factors professional. Following the completion of discovery, Defendant filed motions to exclude the testimony of both experts.

    Mechanical Engineering Expert Witness

    Chad E. Jones is a certified machine safety expert who is licensed in seven states and has worked as an engineer since 1996. He has a Bachelor of Science in Mechanical Engineering from Clemson University. Jones has participated in and led industrial accident investigations and participated in in-depth process safety audits. This work has included equipment design, machine safeguarding, cost estimating and safety compliance. He has designed HVAC and plumbing systems for commercial, industrial, and private clients.

    Want to know more about the challenges Chad Jones has faced? Get the full details with our Challenge Study report. 

    Human Factors Expert Witness 

    Cynthia M. Rando is a certified human factors professional who has worked in the human factors field for approximately twenty years. She is Vice President of the Board of Certification in Professional Ergonomics (Human Factors). Rando received her B.S. and M.S. in Human Factors Engineering from Clemson University and an MBA from Northeastern University. She has also served as an associate professor at University of Houston Clearlake providing instruction in Human Factors, Safety and Ergonomics course material.

    Fortify your strategy by reviewing a Challenge Study detailing grounds for excluding Cynthia Rando’s expert testimony. 

    Discussion by the Court

    Chad Jones

    i. Qualifications

    Defendant argued that Jones was not qualified because, despite being a mechanical engineer, he did not have any experience with the machine at issue or with drum-style drain cleaning machines generally. Defendant also contended that Jones’ purported experience with guarding mechanisms as they relate to industrial machine presses bore no relation to this case, as a machine press was entirely different from a drum-style cleaning machine.

    While Jones’ personal experience with drain cleaners is limited, and he is not familiar with the subject machine, the Court held that his professional experiences qualify him to opine here. Jones is certified as a machinery safety expert and has worked in the area of machine safeguarding since March 2019. True, he may not have actual experience with the particular machine in this case, but he need not be the best expert in the field in order to be qualified.

    ii. Reliability

    Defendant argued that even if Jones’ qualifications pass muster, his opinions are nonetheless unreliable because he failed to perform any testing of his purported reasonable alternative design. Jones opined that Defendant was required to include a fixed guard over the rotating cable to prevent injury. It is undisputed that Jones did not engage in any physical testing of the proposed alternative nor did he conduct any mathematical calculations or models.

    Indeed, Jones conceded that he has not spoken to any users of the equipment or industry professionals nor did he design or test his own fixed guard or physical prototype, use a computer program to design or simulate a fixed guard, perform calculations or drawings to demonstrate how an alternative guard would fit onto the machine, take an exemplar guard and try to apply it to the machine, or perform calculations, modeling, or other analysis to assess if an alternative guard would impact the speed or ability of the cable’s rotation. 

    Plaintiff’s contention that Jones need not test his alternative design is premised upon his assumption that the fixed guard is an “industry standard.” On this point, Plaintiff claimed that three of Defendant’s competitors use a fixed guard and thus the Court should presume this is what the industry requires. But that is too great of a leap in logic.

    Jones did not conduct any type of analysis that would make up for his lack of testing of the proposed alternative design. While Plaintiff contended that Jones included detailed designs, an economic study, preliminary drawings, and his own risk-utility testing, the Court does not find that information on the cited references or anywhere else in the report.

    Cynthia Rando

    After reviewing certain materials and taking Plaintiff’s hand measurements, Rando opined as follows:

    ➢ The primary root cause of the incident involving Plaintiff and the K-6200 Drain Cleaning machine was failure to effectively address hazards created by the design and operation of the K-6200 Drain Cleaning machine through standard design controls.

    ➢ Defendant demonstrated negligence through their failure to effectively assess and control risk and the violation of accepted standards of practice pertaining to risk management and the design for human safety.

    ➢ Additionally, the failure to provide the correct personal protective equipment (PPE), including unsafe recommendations made by Defendant to utilize a “one size” glove that allowed for a loose fit for individuals representing a smaller anthropometric hand size range, introduced unacceptable added risk and significant potential for injury.

    ➢ The reliance on the user manual to provide the necessary information regarding safe operation of the device by Defendant and the expectation that the manual was the hazard control method was negligent. This approach passed the responsibility of safety to the end user despite the awareness of the potential for significant injury based on the design of the equipment and recommended method of operation.

    ➢ The user manual was not written in an easy-to-understand manner, including conflicting safety instructions and recommendations for postures that would create increased risk of injury to the operators.

    ➢ The manual violated ANSI Z535 standards and recommended unsafe operations to the end users but advertised them to be “safe.”

    ➢ These issues represent the root cause and contributing factors to the injury incurred by Plaintiff on August 17, 2019.

    i. Reliability

    Defendant argued that Rando’s opinions on the user manual are irrelevant to the causation analysis and unreliable because she failed to either offer or test any reasonable alternative warnings.

    After reviewing Rando’s expert report, the Court concluded that Rando did not offer a specific opinion about the adequacy of the warning label. Indeed, her opinions as to “Caution and Warnings” are couched in the context of analyzing the user manual which, as noted, Plaintiff did not read.

    Rando never addressed whether the warning label affixed to the machine was inadequate or failed to capture Plaintiff’s attention. Because her opinion focused solely on the user manual Plaintiff never read, the Court held that it is not relevant.

    Even if the Court did interpret Rando’s opinion as encompassing the warning label, her failure to draft or test any proposed alternative warnings still rendered any such opinion unreliable.

    Last, Plaintiff pointed to Rando’s opinion on personal protective equipment (PPE) that Defendant’s standard one size fits all glove—which Plaintiff admittedly did not use here—was unsafe, but that has no bearing on his failure to warn claim. In the end, these “unsafe recommendations” were included in the user manual, which, as already discussed, Plaintiff never read. Therefore, the Court held that her opinion on PPE is similarly irrelevant.

    Held

    The Court granted the  Defendant’s motions to bar the testimony of Plaintiff’s expert witnesses, Chad Jones and Cynthia Rando.

    Key Takeaway:

    An expert can overcome the lack of testing by adhering to the standards of intellectual rigor demanded in their professional work. However, Jones did not conduct any type of analysis that would make up for his lack of testing of the proposed alternative design. 

    Case Details:

    Case Caption: Johnson V. Ridge Tool Manufacturing Company, Inc.
    Docket Number: 1:21cv1939
    Court Name: United States District Court, Illinois Northern
    Order Date: August 22, 2025
  • Human Factors Expert’s Testimony on Dark Patterns Excluded

    Human Factors Expert’s Testimony on Dark Patterns Excluded

    The Federal Trade Commission contended that Amazon tricked, coerced, and manipulated consumers into subscribing to Amazon Prime. According to the FTC, this was accomplished by failing to disclose the material terms of the subscription clearly and conspicuously and by failing to obtain the consumers’ informed consent before enrolling them. The FTC also alleged that Amazon did not provide simple mechanisms for subscribers to cancel their Prime memberships. The FTC sued Amazon.com, Inc. and three of the company’s executives, Neil Lindsay, Russell Grandinetti, and Jamil Ghani.

    Defendants’ expert Craig Rosenberg‘s opening report addresses the FTC’s allegation that Amazon used deceptive practices known as “dark patterns” in user interface design to drive unintended Prime membership.

    Rosenberg’s opening report makes several findings. He stated that there is ambiguity in the definition of the term “dark patterns,” it is difficult to measure clarity in user experience design and subjective evaluations are insufficient to measure this clarity, Amazon’s initiatives to enhance clarity demonstrate a commitment to data-driven user experience refinement, Amazon uses empirical evidence to inform design decisions, there are alternative (non-user experience design) explanations for declines in Prime membership subscriptions following clarity-centered changes, and the absence of objective standards for clarity risks penalizing legitimate business practices. 

    The FTC filed a motion to exclude Rosenberg’s testimony on three grounds. First, it said that his methods are unexplained and unreliable. Second, it said that he is not qualified to testify on the subject of his opinions. And third, it said that his testimony is irrelevant and confusing.

    Human Factors Expert Witness

    Craig S. Rosenberg, Ph.D., is a consultant who provides advanced engineering services for a wide array of companies. He has a Master of Science and Ph.D. from the University of Washington in Human Factors, a multidisciplinary field that studies how people interact with machines, technology, and their environment. 

    Want to know more about the challenges Craig Rosenberg has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    Rosenberg’s opening report, rebuttal report, and deposition testimony all indicate the primary source of his expert opinions is his experience, training, and education as a human factors engineer. However, Rosenberg’s inability to articulate how his education, training, and experience have led him to his conclusions shows that these conclusions are not the product of a reliable method; therefore, the Court held that his testimony is inadmissible.

    Amazon said Rosenberg’s “references to the ‘totality’ of his experiences are not evasions, but acknowledgments that his expert conclusions stem from integrated professional judgment based on decades of interface design.” Even so, Rosenberg must explain how his decades of experience inform his expert conclusions. By his own admission, he cannot do so.

    Held

    The Court granted Plaintiff FTC’s Rule 702 motion to exclude the testimony of Defendants’ expert Craig Rosenberg.

    Key Takeaway:

    Liberally construing Rule 702 in favor of admissibility, Rosenberg’s opinion does not show how his experience informs his conclusions. He draws no methodological nexus between his conclusions and his experience, education, and training, other than to say his conclusions are based on his experience, education, and training. This circular reasoning is insufficiently reliable.

    Please refer to the blog previously published about this case:

    Marketing Expert Employed Techniques Widely Accepted in Market Research Community

    Case Details:

    Case Caption: Federal Trade Commission V. Amazon.Com, Inc., Et Al.
    Docket Number: 2:23cv932
    Court Name: United States District Court, Washington Western
    Order Date: August 11, 2025