Expert Witness Profiler

Tag: Defect

  • Economics Expert Allowed to Opine on Historic Losses

    Economics Expert Allowed to Opine on Historic Losses

    Plaintiff Sergio Romero was hired by Defendant Tribune Media Company (“Tribune”), a national media company that owns and operates various news outlets and television stations, as an Account Executive.

    On or around June 21, 2023, Plaintiff was diagnosed with gastric adenocarcinoma, also known as stomach cancer. To accommodate Plaintiff’s cancer diagnosis, Defendant authorized a medical leave of absence for Plaintiff on October 23, 2023. By February 28, 2024, Plaintiff’s approved FMLA/CFRA leave had been fully exhausted.

    After accommodating Plaintiff’s absence since October 2023, Defendant notified Plaintiff by letter on June 14, 2024 that his employment would be terminated on July 1, 2024 for failure to return from exhausted leave, resulting in Plaintiff filing a wrongful termination suit.

    Defendant filed a motion to exclude the testimony of Plaintiff’s expert witness George A. Jouganatos, Ph.D. while Plaintiff filed a motion to strike or exclude the testimony of Defendant’s expert June Hagen, Ph.D. 

    Economics Expert Witness

    George A. Jouganatos, Ph.D. has been a college lecturer for more than 35 years. He has taught economics, finance, management, ethics, and quantitative analysis at University of California, Davis, University of California,
    Santa Cruz, California State University, Sacramento, and University of San Francisco.

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

    Vocational Rehabilitation Expert Witness

    June Hagen is a vocational expert and Certified Disability Management Specialist with decades of experience in vocational assessments, labor market research, and disability evaluations. Hagen holds a Ph.D. in Clinical Psychology from the California Graduate Institute, an M.A. in Community/Clinical Psychology from Pepperdine University, and a B.A. in Psychology from Pepperdine University. She is certified by the American Board of Vocational Experts and has extensive experience in vocational rehabilitation and disability management.

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

    Discussion by the Court

    A. Defendant’s Motion to Exclude Plaintiff’s Expert

    Defendant argued that Jouganatos failed to submit a detailed and complete written expert report as required by Federal Rule of Civil Procedure 26 as his report failed to contain the facts or data considered by Jouganatos in forming his opinions.

    To begin with, Jouganatos submitted a declaration in which he described his background and qualifications. In relevant part, he stated that his “assignment was to analyze the historic (‘back pay’) economic loss and the present value of future (‘front pay’) economic loss for Sergio Romero.” Moreover, he stated that he “employed a standard forensic economic methodology consisting of: (1) establishing a baseline earnings stream, (2) projecting earnings over worklife expectancy, (3) accounting for benefits, (4) applying wage growth, and (5) discounting to present value using a risk-free rate.”

    The following relevant documents were among those reviewed: Complaint, Romero’s employment record at Tribune, pay advices 2020-2024, resume, and responses to economist’s questionnaire and follow-up questions. Jouganatos calculated back pay as extending from July 1, 2024 to June 1, 2026, and front pay from June 1, 2026 going forward 3.58 years, the remainder of Plaintiff’s projected “worklife.”

    Having reviewed Jouganatos’s report, the Court found it sufficient for the purposes of Fed. R. Civ. P. 26(a)(2)(B)(ii). The report did not reproduce the questionnaire or responses and follow-up questions upon which the expert expressly relied. However, the scope of what Jouganatos testified to is limited and is adequately supported by documents in Defendants’ possession or that were obtainable by Defendant.

    B. Plaintiff’s Motion to Exclude Defendant’s Expert

    Plaintiff moved to exclude the statement of Defendant’s expert witness, vocational rehabilitation expert June Hagen, Ph.D., that Plaintiff could have found work within 23 weeks of his termination. Plaintiff asserted that this testimony should not be permitted because Hagen’s expert witness report failed to identify any substantially comparable positions that were available in December 2024; (2) Hagen’s reliance on Bureau of Labor Statistics to determine Plaintiff could have found comparable employment within 23 weeks from his termination is not based on any facts or evidence of substantially comparable positions in the Sacramento area; and (3) none of the open positions identified in Hagen’s expert witness report met the standard for “substantially similar employment.”

    Hagan’s report identified the documents she reviewed, which included deposition transcripts, court filings, and discovery responses. The report included a summary of Plaintiff’s personal, medical, educational, and work history, as well as his employment skills and history of compensation. The report included a timeline of Romero’s job search, which Hagen stated that she sourced from Plaintiff’s deposition.

    As a result, Plaintiff did not identify any procedural defect in the disclosure of Hagen under Rule 26.

    Held

    • The Court denied Plaintiff’s motion to exclude the testimony of Defendant’s expert, June Hagen, without prejudice to a motion in limine to be scheduled at the Final Pre-Trial Conference.
    • The Court denied Defendant’s motion to exclude the testimony of Plaintiff’s expert, George Jouganatos, without prejudice to a motion in limine to be scheduled at the Final Pre-Trial Conference.

    Key Takeaway

    The expert report must be complete such that opposing counsel is not forced to depose an expert in order to avoid ambush at trial; and moreover the report must be sufficiently complete so as to shorten or decrease the need for expert depositions and thus to conserve resources.

    Case Details:

    Case Caption: Romero V. Tribune Media Co.
    Docket Number: 2:24cv3143
    Court Name: United States District Court, California Eastern
    Order Date: April 23, 2026
  • Materials Science Expert Witness Barred From Opining on the Ladder’s Failure

    Materials Science Expert Witness Barred From Opining on the Ladder’s Failure

    On October 1, 2021, Tate Parker purchased a Tricam Industries, Inc. Gorilla articulated extension ladder (Model GLMPXA-14) from Home Depot in Opelika, Alabama. On February 14, 2022, Parker was injured while using his Tricam ladder to access a residential roof for an insurance-related inspection. At the time of the accident at issue, his job duties included inspecting residential roofs that had endured storm damage.

    Parker filed suit against Tricam on January 22, 2024, claiming the ladder was defectively manufactured and designed.

    Parker identified an expert witness, Barton C. Prorok, Ph.D., to speak to the issue of the cause of the ladder collapse. Prorok opined that the ladder collapsed because one of the upper side rails was twisted, which allowed a rail lock rod to slip out of the locking hole and the ladder to retract with Parker on it.

    Tricam filed a motion to exclude the expert testimony of Prorok, attacking his qualifications given his lack of experience in the ladder industry and attacking his methodology which Tricam argued was unreliable, unscientific, and unhelpful.

    Materials Science Expert Witness

    Barton C. Prorok, Ph.D., is a materials engineer, metallurgist, and chair of the
    materials science and engineering department at Auburn University.

    He holds a Ph.D. in Materials Science and Engineering from the University of Illinois at Chicago. At Auburn University, he also serves as Director of the Analytical Microscopy Cost Center.

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

    Discussion by the Court

    Prorok’s opinions stem, first, from his observation that one of the rails on the subject ladder was twisted upon post-accident inspection. From there, he posits there was a defect in the manufacturing process that caused an upper rail to twist and become distorted. He also believes there is a design defect in the length of the rail lock rods that allowed the rail lock rods to disengage because of the single twisted rail. The combination of the two defects, according to Prorok, caused both upper rails to slip, the upper ladder portion to retract, and the ladder to collapse and fall to the ground.

    To begin with, Prorok visually inspected the subject ladder, took measurements, purchased an exemplar ladder for comparison, inspected the site of the accident, and considered eye-witness accounts from Parker and the son of the homeowner.

    Analysis

    The Court held that Prorok provided no evidence that ladder manufacturers rely on visual inspections or caliper measurements to assess ladder defects. He did not explain how his measurements led to a scientifically reliable methodology. He never conducted tests to determine whether those measurements constituted a defect or unreasonable danger, or caused the ladder collapse. Further, Prorok provided no insight or information supporting his opinion that there was a manufacturing defect that caused the collapse.

    Moreocer, he provided no information or opinions about why that twisting could not have occurred for other common sense reasons such as during the ladder’s transit from China to the United States before sale, or during Parker’s storage, and use of the ladder for months on over 100 occasions, or because of the accident itself.

    And as to the design defect, Prorok opined that the length of the rail lock rods “is a design flaw that reduces load-carrying capacity, especially when manufacturing variations or normal wear and tear occur.” However, he did not explain what those “manufacturing variations” may be, or what impacts to the ladder there may be from “normal wear and tear.”

    As for Prorok’s opinions that the twisting was caused during the metal deformation stage of the manufacturing process, the Court found no evidence about the metal deformation process.

    Nor is there any evidence explaining how the upper part of the ladder, post-accident, was observed to be in the fully extended position while the bottom portion was fully retracted if the accident occurred in the manner that Prorok claims it did.

    Held

    The Court granted Tricam’s motion to exclude the expert testimony of Barton Prorok.

    Key Takeaway:

    Prorok did not produce any literature, reports, or other documentation to support his contention that the accident occurred in the manner that he claims it did. And he tested none of his opinions. Indeed, he performed no testing to duplicate the conditions or manner in which he claims the collapse occurred.

    Case Details:

    Case Caption: Parker Et Al V. Tricam Industries, Inc.
    Docket Number: 3:24cv79
    Court Name: United States District Court, Alabama Middle
    Order Date: May 1, 2025
  • Appliances Expert Witness’ Testimony Fails to Establish the Manufacturing Defect Claim

    Appliances Expert Witness’ Testimony Fails to Establish the Manufacturing Defect Claim

    Roger and Reuki Schutt (the “Schutts”) are the owners of a house located at Canton, Massachusetts. On April 24, 2019, the house sustained water damage resulting in the payment of insurance benefits by Safety to the Schutts. The water damage was determined to have originated from a leak in a water filter system manufactured and sold by EcoWater under the tradename Northstar.

    On October 23, 2019, the filter system was examined at a joint inspection by experts for both EcoWater and Safety. The sump was observed to have a “throughwall crack extending the entire length of the housing,” as well as “additional cracks.” EcoWater did not use annealing in the production process for its clear sumps. Post-mold annealing is the process of cooling a mold-injected polymer after manufacture.

    On April 4, 2022, Plaintiff Safety Insurance Company (“Safety”) filed suit in Massachusetts Superior Court against Defendant EcoWater Systems, LLC (“EcoWater”), asserting its right of subrogation arising from water damage to the property of Roger and Reuki Schutt. 

     Safety disclosed two experts in support of its case: (1) “appliance failure inspector” expert Thomas Zarek and (2) materials science expert Timothy Kenney. 

    Zarek opined that the product failed prematurely at the loss location and caused the water damage while Kenney concluded that it was common practice to post-mold anneal these thick wall parts to reduce these residual stresses and improve the performance of the part.

    EcoWater filed motions in limine to exclude the opinions and testimony of Thomas Zarek and Timothy Kenney under Rule 702.

    Appliances Expert Witness

    Thomas Zarek has been employed as an appliance failure inspector since 1997. Regarding his areas of expertise, Zarek holds himself out as a warnings expert, a certified fire and explosion investigator, a certified vehicle fire investigator, and a licensed oil heating inspector and installer. Also, he has taken “a number of courses on appliance failure analysis and on HVAC systems installation,” covering a variety of appliances and materials, including polymers and metals.

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

    Materials Science Expert Witness

    Timothy Kenney’s qualifications and experience include a degree in geology, undergraduate engineering courses in materials science, graduate courses in metallurgy, ceramics, and selection of steels, and various publications. Besides, he serves as the Laboratory Director of New Hampshire Materials Laboratory.

    NHML provides consulting and technical services in chemical, materials, mechanical design, and industrial processing.

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

    Discussion by the Court

    Thomas Zarek

    To begin with, Safety’s complaint claimed negligence and breach of warranty based solely on defective manufacture of the filter system. Therefore, the Court held that Zarek’s opinions as they relate to other theories of negligence, such as failure to reasonably warn or defective design, are irrelevant since any expert testimony must therefore be limited to establishing the manufacturing defect claim.

    Zarek testified that his conclusions regarding the filter system’s allegedly premature failure are based, at least in part, on his review of EcoWater’s Test ID 4499, which tested canisters similar to the subject sump through a cycle test and hydrostatic test. Yet, the Court found that Zarek himself admitted that he has never performed a cycle test himself for any kind of product and that he does not know what cycle testing is intended to evaluate. As for the hydrostatic testing, Zarek likewise testified that he has never conducted a hydrostatic test on a polymer product or on the styrene acrylonitrile (“SAN”) material used in the subject product, and that the purpose of a hydrostatic test is not to test to failure.

    The Court held that Zarek’s lack of relevant experience and knowledge pertaining to the claims alleged makes clear that he is not qualified to offer expert testimony here.

    Second, the Court held that Zarek’s opinions reflected little to no expert analysis or review done by Zarek. Several of his proffered opinions merely repeated Kenney’s conclusions, without adding anything more. He stated that he personally did no analysis of the data from the testing performed by Kenney.

    Timothy Kenney

    In opining that post-mold annealing is a “general industry practice,” Kenney exclusively relied on the ASM International Volume 2 of the Engineered Materials Handbook. The Court held that Kenney himself undermined the relevance of this guidance where he testified that there is a difference between thick-section and heavy wall parts, that the subject sump is a thick-section part, and that the ASM handbook only recommends post-mold annealing for heavy-wall parts and not thick-section parts.

    Also, he conceded that he did not conduct any testing to evaluate the effects of post-mold annealing on the product and whether such annealing would have alleviated residual stress, nor has he seen any studies or test reports to that effect.

    Moreover, EcoWater also filed a motion for summary judgment seeking to dismiss the case entirely. The Court held that where Safety has no expert support for its claims—which, again, arise exclusively from allegations of negligent manufacture—Safety’s claims cannot survive summary judgment.

    Held

    To sum it up, the Court granted EcoWater’s motions in limine to exclude Plaintiff’s experts, Thomas Zarek and Timothy Kenney as well as his motion for summary judgment.

    Key Takeaway:

    In conclusion, the Court held that many of Zarek’s opinions reflected little to no expert analysis or review done by Zarek. While Zarek’s opinions were irrelevant to Safety’s claims regarding negligent manufacture of the filter system, Kenney had no basis to opine as to whether post-mold annealing would have prevented the subject product from failing here, after fourteen years of use.

    Case Details:

    Case Caption: Safety Insurance Company Et Al V. Ecowater Systems, Llc
    Docket Number: 1:22cv10887
    Court: United States District Court, Massachusetts
    Order Date: May 17, 2024
  • Firearms & Ballistics Expert Witness Testimony Rejected for not being based on Empirical Evidence

    Firearms & Ballistics Expert Witness Testimony Rejected for not being based on Empirical Evidence

    In January 2021, Timothy Davis experienced an unexpected discharge of his Sig Sauer P320 XCarry pistol while exiting his vehicle, resulting in a severe leg injury from a 9mm hollow-point bullet. The circumstances surrounding the incident were unclear, with conflicting accounts in Davis’ deposition. He stated that, while sitting in his vehicle, he holstered the P320, and as he extended his leg, the pistol discharged. Davis insisted that the P320 was fully holstered and secured on his left hip.

    However, a police report and an EMT report provided a different version, indicating that Davis was attempting to holster the P320 when the discharge occurred. Regardless, Davis claimed the P320 discharged without a trigger pull, a contention disputed by Sig Sauer.

    In January 2021, Plaintiff Timothy Davis claimed that his Sig Sauer P320 XCarry pistol discharged unexpectedly, injuring his leg with a 9mm hollow-point bullet. Davis provided conflicting accounts of the incident: one stating he holstered the gun before exiting the vehicle, and another suggesting he was attempting to holster it when the discharge occurred.

    Davis filed a product liability and negligence lawsuit against Sig Sauer, alleging that the P320 lacked external safeties, making it unreasonably dangerous. Gunsmith James Tertin and human factors engineer William Vigilante, serving as expert witnesses, argued that the absence of a manual safety rendered the pistol defective, increasing the risk of accidental discharge. They contended that this defect was the proximate cause of Davis’ injury.

    Sig Sauer moved to exclude Tertin and Vigilante’s opinions and sought summary judgment, claiming that without the expert testimony, there was no genuine dispute of material fact, and Davis failed to establish causation.

    Firearms & Ballistics Expert Witness

    James Tertin is currently the director of research and development for Magnum Research, a firearms manufacturer based in Pillager, Minnesota. In that role, he is responsible for designing and developing new firearms for the company.

    He has been a professional gunsmith since graduating in 1972 from the Gunsmithing School at Trinidad State College in Colorado; the oldest gunsmithing school in the United States. Over the past fifty years, he has been awarded seven firearm design patents.

    Human Factors Engineering Expert Witness

    William Vigilante graduated with a Doctoral of Philosophy and a Master’s of Science in Ergonomics (Human Factors) Psychology and a Bachelor of Science degree in Psychology (Cognitive track). He is also a Certified Professional Ergonomist by the Board of Certification in Professional Ergonomics (#2019). He has more than 25 years of experience in psychological and human factors research with a focus on human-machine interaction, control-display design, product design, hazard identification and mitigation, risk perception, situational awareness, perception-reaction time, and the design and testing of warning systems.

    Discussion by the Court

    Federal Rule of Evidence 702 governs the admissibility of expert witness testimony. It permits an expert to testify about scientific knowledge if “(a) the expert’s scientific, technical, or other specialized knowledge will help the trier of fact to understand the evidence or determine a fact in issue; (b) the testimony is based on sufficient facts or data; (c) the testimony is the product of reliable principles and methods; and (d) the expert has reliably applied the principles and methods to the facts of the case.”

    Sig Sauer had challenged the testimony of Tertin and Vigilante on various grounds, asserting that their causation opinions were speculative and lacked reliable foundations. Additionally, Sig Sauer questioned Vigilante’s qualifications to opine on firearm design. Sig Sauer’s primary objective was to exclude Tertin and Vigilante from expressing the view that Davis’ accident might have been prevented with a thumb safety or tabbed trigger safety on the P320.

    The Court concurred with Sig Sauer’s argument, finding that neither Tertin nor Vigilante had a reliable factual basis for their causation opinions. Tertin’s opinion, which stated that any single-action firearm without a manual thumb safety is defective, lacked empirical evidence. Tertin suggested that a tabbed trigger “probably would have prevented the accident,” but he admitted to having no information about what caused Davis’ trigger to depress. Tertin performed no analysis on the circumstances of the accident, providing no basis for his conclusion on the lack of a manual safety being the proximate cause. The Court deemed Tertin’s opinion as pure speculation, lacking any factual foundation or empirical evidence, and therefore inadmissible for proving causation.

    Vigilante’s opinion faced a similar challenge. He contended that the P320’s lack of an external manual safety made it defective and unreasonably dangerous, attributing it to the unintentional discharge in Davis’ case. According to Vigilante, triggers could move through inertia, foreign object contact, or contact with a body part, but he lacked an opinion on how Davis’ trigger became engaged.

    Vigilante admitted to not inspecting Davis’ pistol or holster, relying solely on Davis’ deposition and a sheriff’s report for his understanding of the accident. He did not speak with Davis or review the first responders’ testimony, and no testing or analysis of physical evidence was conducted to validate Davis’ version of the accident. Vigilante’s causation opinion appeared detached from the specific circumstances of Davis’ case, relying on a general conclusion about the P320’s safety without factual support.

    Even Vigilante’s generalized conclusions were based on shaky grounds, using anecdotal data from YouTube videos and a memorandum by the United States Immigration and Customs Enforcement Agency. This lack of empirical evidence failed to meet the standards set by Rule 702 for expert testimony. Even if one assumed the absence of a manual safety was a design defect, Vigilante provided no factual basis for concluding that a manual safety would have prevented Davis’ specific accident. Without a thorough investigation into the accident’s circumstances, Vigilante’s causation opinion was deemed too speculative and lacking reliability. Therefore, his expert testimony was precluded.

    The Court briefly addressed another argument asserted by Davis in support of admitting the expert testimony of Tertin and Vigilante. Davis compared two recent Orders from other district courts that considered similar motions filed by Sig Sauer. In the Northern District of Georgia, Sig Sauer’s motions were partially denied, while in the Western District of Oklahoma, Sig Sauer’s motions were granted. Davis urged the Court to distinguish the Western District of Oklahoma case, Herman V. Sig Sauer, asserting that the facts in the present case were distinct.

    After reviewing both Orders and their supporting records, the Court concluded that Herman was not distinguishable, particularly concerning the reasoning supporting the exclusion of expert testimony by Tertin and Vigilante. Despite the Northern District of Georgia recognizing that the opinions of Tertin and Vigilante were based on the specifics of the incident in that case, the Court found no similar evidence in the present case. Similar to the Herman Court, the Court noted broad conclusions about an alleged defect in Sig Sauer’s P320 applied generally to the case’s facts. Tertin and Vigilante both admitted that the specific circumstances of Davis’ incident weren’t crucial to their opinions. Therefore, as explained above, neither expert could be relied upon to provide an accurate and helpful opinion on what may have caused the injury in Davis’ particular case. Consequently, both experts were precluded from testifying.

    With the exclusion of Tertin and Vigilante, Davis found himself without any expert witness to testify regarding the alleged defect and causation. This absence meant that Davis could not demonstrate the existence of a defect and its role in causing his injury. Consequently, his claims lacked an essential element and failed under Kentucky law. As a result, the Court granted Sig Sauer’s motion for summary judgment.

    Held

    The Case was decided in Defendant, Sig Sauer’s favor after the testimony of both experts, James Tertin and William Vigilante were excluded and Sig Sauer’s motion for summary judgment was granted.

    Key Takeaways:

    The admissibility of expert witness testimony is governed by Federal Rule of Evidence 702, which sets criteria requiring the expert’s knowledge to assist the trier of fact, be based on sufficient facts and data, use reliable principles and methods, and be reliably applied to the case’s facts. In the case against Sig Sauer, challenges were raised against the expert testimony of Tertin and Vigilante, asserting that their causation opinions were speculative and lacked reliable foundations. Additionally, Vigilante’s qualifications to opine on firearm design were questioned. The Court, agreeing with Sig Sauer’s arguments, found that neither expert had a reliable factual basis for their causation opinions, rendering them inadmissible under Rule 702 due to a lack of empirical evidence and factual support. Both experts were criticized for offering broad conclusions about an alleged defect in Sig Sauer’s P320, which were then applied generally to the case’s facts, leading the Court to deem their opinions speculative and lacking a specific connection to the incident in question. Vigilante’s reliance on anecdotal data and Tertin’s admission of no empirical evidence were cited as failures to meet the standards set by Rule 702, which requires a reliable basis for expert opinions. Attempts by the Plaintiff to distinguish the present case from others with varying outcomes were rejected by the Court, emphasizing the lack of similar evidence showing the experts’ opinions were based on the specific circumstances of the incident. With the exclusion of expert testimony, the Plaintiff was unable to demonstrate the existence of a defect and causation, resulting in the failure of claims under Kentucky law. As a consequence, the Court granted Sig Sauer’s motion for summary judgment, underscoring the critical role that expert testimony can play in product liability cases.

    Case Details:

    Case Caption Davis v. Sig Sauer, Inc.
    Docket Number 3:22cv10
    Court United States District Court for the Eastern District of Kentucky, Central Division
    Citation 2024 U.S. Dist. LEXIS 1796
    Order Date January 4, 2024