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  • Obstetrics and Gynecology Expert’s Opinion on Amniotic Fluid Embolism Admitted

    Obstetrics and Gynecology Expert’s Opinion on Amniotic Fluid Embolism Admitted

    Mikaznaaz Saiyed tragically passed away after giving birth at Swedish Covenant Hospital. She became unconscious during labor, and the delivery team had to perform an emergency C-section. Before long, she went into cardiac arrest, and the medical team rushed her to the intensive care unit. She passed away a few days later from a rare, life-threatening condition that sometimes occurs in pregnant women.

    Her husband, Ahzar Saiyed, brought medical negligence claims against three Swedish Covenant entities, plus two members of the medical team. The United States later joined the case in place of the doctor and the midwife, because they worked for federally funded clinics.

    Saiyed retained an expert, Dr. Martin Gubernick, to explain what went wrong in the delivery room. He issued a 24-page report that summarized how things unfolded in the hospital that day, including the medical care that Mrs. Saiyed received.

    Gubernick addressed the cause of her injuries. He opined that the improper use of medications caused Saiyed to have uterine tachysystole, meaning excessive contractions. Gubernick believed that “her uterus was not given sufficient time to relax.” He also opined that the excessive contractions likely caused Saiyed to experience amniotic fluid embolism. 

    As Defendants see things, Saiyed cannot prove what caused the amniotic fluid embolism. They believe that the testimony of Gubernick is inadmissible under Daubert. And without his testimony, Saiyed cannot carry his burden of proof.

    Obstetrics and Gynecology Expert Witness

    Dr. Martin Gubernick is a board-certified obstetrician gynecologist with over forty years of experience in obstetrics and gynecology. Gubernick attended medical school at Northwestern University, and he did his residency at New York Hospital – Weill Cornell Medical Center in obstetrics and gynecology.

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

    Discussion by the Court

    A. Qualifications

    Defendants argued that Gubernick is unqualified to testify about amniotic fluid embolism. They basically identified a bunch of omissions in his CV. As Defendants pointed out, Gubernick has never published any medical literature on amniotic fluid embolism, and has never lectured on the topic. He has not researched that condition in particular. And he has never managed a labor and delivery involving a mother with amniotic fluid embolism.

    However, Gubernick has loads of practical experience in delivery rooms. He has given drugs to induce labor, and is familiar with Cytotec and Pitocin, the two drugs at issue in this case. He has performed C-sections, monitored patients, and “overseen massive transfusions of blood products for conditions like amniotic fluid embolism.”

    Gubernick has knowledge about amniotic fluid embolism, too. He is “familiar with amniotic fluid embolism including but limited to its pathophysiology, causes, treatments, and outcomes.” Gubernick is a physician trained in the area of pregnancy and childbirth. He has extensive experience with related drugs, procedures, and conditions. That experience gives him sufficient qualifications to take the witness stand.

    Based on his report, Gubernick intended to explain to the jury what amniotic fluid embolism is, and how it happens. “Amniotic fluid embolism is a condition in which amniotic fluid (likely with fetal hairs, cells, and other material, etc.) enter the mother’s blood stream triggering what is akin to an allergic reaction. The amniotic fluid can leak into the mother’s blood stream, prompting mom’s body to ‘reject’, or ‘fight off’ what it senses is an attacker.”

    Overall, Gubernick may not be an expert in amniotic fluid embolism per se. But he has substantial expertise in the area of pregnancy and childbirth. He has sufficient background and expertise to explain amniotic fluid embolism to the jury.

    B. Methodology

    Defendants believed that Gubernick lacked a basis to opine about what caused Saiyed to suffer an amniotic fluid embolism.

    At bottom, Gubernick offered an opinion with two links in the causal change. He opined that Cytotec likely caused Saiyed’s uterine tachysystole (again, the excessive contractions). And he opined that the uterine tachysystole likely caused her amniotic fluid embolism.

    Basically, the medication caused her uterus to go into overdrive, which led to a rupture. And the rupture caused a mixing of the fluid between the mother and the child.

    Defendants took issue with both steps in the causal chain. A chain is only as strong as its weakest link. But here, each of the links is strong enough to get to a jury.

    The first link is the connection between the medication and the medical condition. Gubernick opined that it is “well recognized” that Cytotec can lead to uterine tachysystole.” The Court found that Gubernick had a sufficiently reliable basis for reaching that conclusion. After all, the package insert itself warns physicians that a “major adverse effect of the obstetrical use of Cytotec is uterine tachysystole.”

    A package insert doesn’t come out of nowhere. A package insert needs to receive the blessing of both the FDA and the drug manufacturer. And that approval comes after rigorous review and testing. Medical professionals kick the tires on anything said in a package insert because it affects how physicians use the medication with patients.

    Gubernick based his opinion on the package insert, and the package insert reflected the understanding of the medical community. The whole point of a package insert is its reliability. It’s a go-to source for reliable information about how to use a drug, and what side effects might follow. Maybe a package insert is over-inclusive. But it doesn’t have to provide definitive gospel truth for an expert to rely on it.

    The second link is the connection between the two medical conditions. Gubernick opined that the excessive contractions likely caused the amniotic fluid embolism. The Court held that Gubernick relied on the FDA-approved package insert, and he offered an explanation of how excessive contractions can lead to a rupture. That’s a sufficiently reliable basis to get in front of a jury. Any problems with his theory are best left for cross examination.

    Held

    Overall, the Court found that the opinions of Dr. Martin Gubernick pass muster under Daubert and Rule 702. Gubernick has the qualifications to give his opinions, and the opinions have sufficient indicia of reliability to get to a jury. Beyond that, the jury will have to figure it out.

    Key Takeaway

    An expert does not have to foreclose other possibilities when it comes to causation. And a Plaintiff doesn’t have to prove that negligence is the only explanation. Instead, an expert simply needs to offer an opinion that is sufficiently reliable to put before the jury. Basically, district courts stand guard and protect juries from unreliable experts. But once an expert offers a sufficiently reliable opinion, it is up to the adversary process to find the truth. 

    Case Details:

    Case Caption: Saiyed V. Swedish Convenant Hospital
    Docket Number: 1:20cv5524
    Court Name: United States District Court, Illinois Northern
    Order Date: March 24, 2026
  • Environmental Engineering Experts’ Source-Identification Conclusion Excluded

    Environmental Engineering Experts’ Source-Identification Conclusion Excluded

    In this water contamination case, Defendants Dow Chemical Company and Vibrantz Corporation (collectively, “Defendants”) challenge the proof which Plaintiff Suffolk County Water Authority (“Suffolk”) proffers through its expert witnesses that dioxane-stabilized TCA is the source of the contaminant 1,4-dioxane in what it calls the TCA Claim Wells.

    Defendants did so through the opinions of their own expert witnesses John A. Connor and David T. Adamson. Suffolk did not challenge the bulk of the Connor/Adamson opinions, which are rebuttals to Suffolk’s experts. Rather, Suffolk filed a motion to exclude one subset of those opinions, namely, those opinions which affirmatively assert well-by-well conclusions as to source identification of the 1,4-dioxane in the wells.

    Environmental Engineering Expert Witnesses

    John A. Connor has over forty years of experience in environmental engineering, including specialization in “environmental site investigation, human health and ecological risk assessment, corrective action design, water resource development and remediation, and design and permitting of treatment facilities.” 

    He received an M.S. in Civil Engineering from Stanford University and is a registered Professional Engineer, a licensed Professional Geoscientist, and a Diplomate in the American Academy of Environmental Engineering.

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

    David T. Adamson received his Ph.D. in Civil and Environmental Engineering from the University of Iowa and has over twenty-two years of research and environmental consulting experience. He has conducted research and authored technical articles on a wide range of topics related to subsurface contamination, including serving as Principal or co-Principal Investigator on research projects sponsored by the U.S. Department of Defense on topics such as 1,4-dioxane fate, transport, and treatment. Adamson has also consulted on a broad range of topics, including “chemical fate and transport, site investigation, remedy screening, risk assessment, remedial design, drinking water distribution, and litigation matters.”

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

    Discussion by the Court

    II. The Connor/Adamson Report

    Connor and Adamson opined that TCA is the source of the 1,4-dioxane in only a small fraction of the TCA Claim Wells. Rather, they asserted, that the predominant source is septic system and wastewater releases. This conclusion appears in Section 3.3 of their Report, which consisted of pages 70-76 out of 160 pages, plus a mass of appended charts. Connor and Adamson opined that they identified ten relevant “lines of evidence” and that they used a “weight-of-evidence” methodology to assess the likely source of 1,4-dioxane in each of the TCA Claim Wells.

    The lines of evidence include, for example, TCA detections in each well, and land use within the capture zone. Section 3.3 contains an explanation of the lines of evidence as well as the experts’ ultimate conclusions that the weight of the evidence is consistent with a septic system and wastewater source of 1,4-dioxane in the vast majority of well fields containing TCA Claim Wells.

    Upon review of the Connor/Adamson Report and the appended charts, the Court found that there was in fact no well-by-well analysis in the report or in the charts.

    In the Report, Connor and Adamson did not assign numeric weight to the various lines of evidence or follow a decision tree to reach an ultimate conclusion.

    Analysis

    Defendants acknowledged that Section 3.3 contains only (1) a discussion of the ten lines of evidence and (2) Connor and Adamson’s ultimate conclusions as to the likely source of 1,4-dioxane in each of the TCA Claim Wells.

    Indeed, review of these appendices reveals a complete absence of analysis as to how the experts reached those final conclusions. Put another way, it is impossible to glean what the experts’ thought processes were in considering the cumulative effect of the thousands of data points that make up the purported “full form” well-by-well analysis.

    The Court rejected Defendants’ argument that the detailed narratives through which the experts intended to present their testimony, which they estimate could take up to three hours per well, can be discerned merely by looking at the charts. On the contrary, it is clear that Defendants intended to use the trial testimony to supply the missing explanations as to how each line of evidence factored into the ultimate conclusion as to each well.

    Indeed, if the charts themselves were a sufficient basis for understanding the experts’ reasoning in reaching their ultimate source identification conclusions, as the Defendants contended, then—after the experts’ general testimony applicable to all wells—the Defendants would need only to present the charts to the jury. 

    There is no way for the Court to evaluate whether the methods the experts used or the judgment they applied was reliable or not. As an example of why this is important, consider the undisputed fact that, with respect to some wells, the experts’ lines of evidence point to inconsistent or conflicting results as to the source of the 1,4 dioxane. Nowhere did the experts provide any analysis of how they resolved—or can resolve—such inconsistencies or conflicts. Rather, it is clear that their application of judgment is separate for each well, yet no effort has been made in the Report to set forth how those individual judgments were made.

    Finally, Defendants’ suggestion that they can have their experts describe in narrative form how they reached their source identification conclusions well-by-well for the first time at the trial, without having provided their analyses pre-trial, violated fundamental principles of pre-trial expert discovery.

    Held

    The Court granted Suffolk’s motion to exclude John Connor and David Adamson’s well-by-well assessment of dioxane sources.

    Key Takeaway

    The question is not simply whether Connor and Adamson may consider various lines of evidence together in reaching a conclusion. Rather, as explained above, the problem is that their Report does not present any analysis of how the various lines of evidence led them to their ultimate conclusions. In these circumstances, the Court is unable to determine the reasoned bases for Connor and Adamson’s analysis and whether it is truly reliable “at every step.”

    Case Details:

    Case Caption: Suffolk County Water Authority V. The Dow Chemical Company
    Docket Number: 2:17cv6980
    Court Name: United States District Court, New York Eastern
    Order Date: March 23, 2026
  • Economics Expert’s Earning Capacity Analysis Admitted

    Economics Expert’s Earning Capacity Analysis Admitted

    This case involves a workplace accident that occurred on July 13, 2023, while Plaintiff Jason Flores (“Plaintiff”) was working at ACS Manufacturing, Inc. (“ACS”) with a press brake machine (“Subject Press Brake”) manufactured by Accurpress.

    Plaintiff’s left hand was severely injured when the ram on the Subject Press Brake came down on his hand after he reached into the machine’s point of operation to retrieve a piece of debris.

    Plaintiff has brought a strict product liability claim alleging a marketing defect and a negligence claim alleging that Accurpress failed to exercise reasonable care in warning operators.

    Accurpress America, Inc. raised several arguments for excluding the opinions of Plaintiff’s economist, Lisa McGuff and prosthetics expert, Chris Lake.

    Economics Expert Witness

    Lisa McGuff has over 20 years of experience in economics and decision analysis. McGuff specializes in litigation and policy support for individuals, government, and the private sector. Her experience includes valuation and damages analysis, pricing, forecasting, royalties, and statistical analysis across a range of industries including energy, employment, real estate, and franchises.

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

    Prosthetics Expert Witness

    Chris Lake, L/CPO, FAAOP(D) is a Licensed and Certified Prosthetist Orthotist. Lake is a Fellow with Distinction of the American Academy of Orthotics and Prosthetics.

    Lake graduated from the University of Texas Southwestern Medical Center Prosthetics and Orthotics program in 1995. He completed a Prosthetic Residency (1996) at Southern Illinois University and an Orthotic Residency (1997) at the University of Oklahoma.

    Lake has specialized in upper-limb prosthetics since 1997.

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

    Discussion by the Court

    1. McGuff Daubert

    First, Accurpress argued that McGuff’s earning capacity analysis should be excluded under Daubert because she allegedly failed to calculate damages as a measure of Plaintiff’s future earning potential subtracted from his past potential. Second, Accurpress complained that these same capacity opinions are improper because McGuff assumed he would be employed as a “steel worker” until the age of sixty-seven, a job in which he had his highest earnings, and which he left before the time of his accident. Third, Accurpress argued that McGuff’s analysis of household labor should be excluded because she allegedly does not account for Plaintiff’s post-injury capability to perform household labor. Fourth, Accurpress argued that McGuff’s earning capacity and household labor analyses should be excluded under Rule 403 because such analyses will be “confusing and misleading” without comparison to Plaintiff’s post-injury abilities.

    As the Court explained during the hearing, loss of earning capacity is different from lost wages, and, while it is helpful to compare after-injury earnings, that is not required here. Plaintiff counsel also persuasively raised during the hearing that there will be evidence that his current position is as a sheltered employee, which could end prematurely and may not properly reflect his future earnings. Moreover, McGuff’s calculations represented familiar calculations within the purview of an economist based on actuarial data that is typical in a tort case such as this one.

    Therefore, the Court found that McGuff’s earning capacity and household labor opinions are sufficiently relevant and reliable to survive Daubert.

    2. Lake Daubert

    First, Accurpress argued that Lake’s opinion that Plaintiff needed prosthetics is unreliable because he did not consult “treating physicians” or conduct “functional capacity exams.” Second, Accurpress complained that Lake’s opinions on the maintenance costs (ranging from 10-20% of the cost of the prosthesis) of the three he recommends are based solely on his experience and are inconsistent with alleged normative industry data (reflecting 3%). During the hearing, Accurpress’ counsel raised an additional argument that Lake’s opinions on the prosthesis are unreliable because Plaintiff has not had an amputation yet in the two-and-a-half years since his accident, which is a prerequisite to fitting a prosthesis.

    While Accurpress raised a slew of additional arguments, it provided no basis for such arguments grounded in Lake’s opinions or the facts. As a result, the Court found that Lake’s prosthetics opinions are sufficiently reliable.

    Held

    The Court denied Accurpress’ motions to exclude the opinions of Lisa McGuff and Chris Lake.

    Key Takeaway

    For expert testimony on topics that lack exactness, courts should consider factors such as the expert’s professional experience. Rule 702 does not prohibit an expert from reaching an opinion based on the expert’s experience and a witness’ experience can provide a reliable basis.

    Case Details:

    Case Caption: Flores V. Capital Machine Technologies, Inc.
    Docket Number: 2:24cv81
    Court Name: United States District Court, Texas Eastern
    Order Date: March 16, 2026
  • Biology Expert Was Not Allowed to Opine on Religious Philosophy

    Biology Expert Was Not Allowed to Opine on Religious Philosophy

    This lawsuit arises from the COVID-19 pandemic, and the City of Ann Arbor’s denial of religious exemptions to Plaintiffs, former City employees, from its mandatory COVID-19 vaccination policy. As the lawsuit currently stands, Plaintiffs Jennifer Alexa, Jeff Malone, and Tim Rugg alleged that the City of Ann Arbor (“City”) failed to accommodate their religious beliefs in violation of Title VII of the Civil Rights Act of 1964 (“Title VII”) and Michigan’s Elliott-Larsen Civil Rights Act.

    The City sought to disqualify the expert report and testimony of Kyle C. McKenna, Ph.D., a biology professor and ocular immunologist, who Plaintiffs retained to discuss the development of the different COVID-19 vaccines, the role of fetal cells in the vaccines’ development and in other pharmaceutical research, and any ties between fetal cells and five over-the-counter (“OTC”) medication.

    Biology Expert Witness

    Kyle Christopher McKenna, Ph.D. is a professor of biology at the Franciscan University of Steubenville, with over twenty-five years of research experience in immunology, the study of the immune response.

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

    Discussion by the Court

    McKenna intended to address the belief that COVID-19 vaccines were developed in the same fashion as these OTC medications with respect to the utilization of fetal cells. He then intended to discuss the reliance on an employee’s use of these OTC medications to assess whether the employee has a sincerely-held religious belief justifying the refusal to receive a COVID-19 vaccine.

    The City, however, maintained that McKenna’s opinions exceeded his area of expertise and extended to theology, as he addresses religious beliefs concerning vaccination and OTC medications.

    Analysis

    Contrary to the City’s assertion, many of the opinions offered by McKenna did not exceed his knowledge, skill, experience, training, or education, by crossing over into theology. His explanation of how COVID-19 vaccines and OTC medications were developed, and his comparison of their development in connection with fetal cells, will be helpful to the jury in assessing whether Plaintiffs’ claimed religious beliefs precluded them from being vaccinated. However, McKenna goes further in his opinions when he discusses religious philosophy with regard to whether the use of fetal cells in the development of vaccines and OTC medications is sufficiently remote to permit an individual to be vaccinated or use those OTC medications.

    McKenna is not trained in religious theory, and he expressly acknowledged that he is not a religious scholar. Aside from being able to share his own beliefs as a Catholic—which are irrelevant to this lawsuit, particularly as no Plaintiff is Catholic— McKenna lacked the qualifications to provide expert testimony on how Plaintiffs’ specific religious beliefs impact their view of the use of fetal cell lines in drug development. Even if McKenna professed to be a religious scholar, he did not interview Plaintiffs to gain an understanding of their specific religious views with respect to the issue. Moreover, he expressly acknowledged that different people have different religious approaches to the problem.

    The Court held that McKenna may provide testimony regarding the development of vaccines and OTC medication, particularly the role of fetal cell lines in their development. However, he is precluded from testifying on how, from a religious perspective, that development impacts an individual’s willingness to be vaccinated or use the OTC medications.

    Held

    The Court granted in part and denied in part the City’s motion to disqualify Dr. Kyle McKenna.

    Key Takeaway

    The Court’s task in assessing reliability is not to decide whether the expert’s opinion is correct, but whether it rests upon a reliable foundation, as opposed to, say, unsupported speculation. Further, rejection of expert testimony is the exception, rather than the rule.

    Case Details:

    Case Caption: Alexa V. City of Ann Arbor
    Docket Number: 2:22cv13073
    Court Name: United States District Court, Michigan Eastern
    Order Date: March 18, 2026

  • Emergency Medical Services Expert Was Allowed to Opine on Scene Safety

    Emergency Medical Services Expert Was Allowed to Opine on Scene Safety

    This litigation stems from the death of Charles Lamar Vanlandingham in September of 2019. Plaintiff alleged that Vanlandingham suffered a medical episode with seizure activity in the early morning hours of September 15, 2019, and Vanlandingham’s girlfriend called 911. According to Plaintiff, Vanlandingham started to improve in the time it took EMS to arrive. Following the seizure activity, Vanlandingham had apparently transitioned to a “postictal state” that can cause confusion.

    Although Vanlandingham was initially compliant with EMS upon their arrival, Plaintiff alleged that “EMS providers tried to force Vanlandingham onto their medical cot,” and when Vanlandingham did not comply, “[EMT] Tuttle ultimately tackled Vanlandingham onto the medical cot.”

    Once members of the Oklahoma City Fire Department arrived, Plaintiff alleged that the Firefighters used their body weight to pin Vanlandingham in the prone position for approximately three minutes before Oklahoma City Police Officer Brandon Lee arrived. Officer Lee then put handcuffs on Vanlandingham—still in the prone position—and placed his knee across Vanlandingham’s back.

    Plaintiff alleged that Vanlandingham was in this position, handcuffed, for approximately four minutes, during which time “no one checked Vanlandingham’s vitals or advocated for a position change despite Vanlandingham’s clear signs of respiratory distress.” “Without knowing Mr. Vanlandingham’s vitals and without performing any kind of medical assessment,” EMT Tuttle then administered midazolam (a sedative), and Vanlandingham went limp. CPR efforts were unsuccessful, and Vanlandingham died at the scene.

    Plaintiff’s claims are against Defendants City of Oklahoma City, Officer Brandon Lee, and American Medical Response Ambulance Service, Inc. (AMRAS).

    During discovery, AMRAS disclosed an expert report prepared by Jim Morrisey, EMT-Paramedic, M.A. Plaintiff contended that Morrissey’s opinions are not reliable as he has failed to provide a basis for his opinions.

    Emergency Medical Services Expert Witness

    Jim Morrisey, EMT-Paramedic, M.A is a certified and licensed paramedic in the state of California and former police officer. He holds both undergraduate and graduate degrees. His entire career has been focused on the field of emergency medicine and education including as a college level adjunct professor in emergency medicine.

    Over the last 35 years he has been involved in emergency medicine as a field practitioner, critical care paramedic, flight paramedic, backcountry wilderness paramedic and as an imbedded tactical paramedic with the San Francisco FBI SWAT team.

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

    Discussion by the Court

    I. Morrissey’s supplemental report is timely

    Morrissey supplemented his expert report on May 28, 2025. In it, Morrissey expands on four of his opinions listed in his initial report but predominately provides supplemental explanations for the purported basis of his opinions. Plaintiff contended that Morrissey’s supplemental report is untimely under Rule 26.

    Here, the parties’ deadline for final witness and exhibit lists and discovery expired before Morrissey issued his supplemental report. However, Rule 26(a)(3) also refers to the deadline to file deposition designations, which has yet to expire. Accordingly, the Court found that Morrissey’s supplemental report is timely under Rule 26(e)(2).

    II. Daubert Motion

    Plaintiff argued that Morrissey should not be permitted to testify regarding his opinions because he did not identify how his experience in the emergency medicine services field led to his specific opinions or what he relied upon in reaching his opinions. Plaintiff asserted that Morrissey’s explanation of the purported basis of his opinions is insufficient, as they are too generalized to test Morrissey’s conclusions for their reliability.

    Upon review of Morrissey’s supplemental report, the Court found that he, at times, failed to adequately identify the basis of his opinions or explain how certain standards or his experience led to his conclusions. Morrissey’s experience in emergency medical services, standing alone, is not sufficient to support his opinions.

    By referring to the protocols and textbook as a basis for his opinion, Morrissey narrowly answers the question of what standards, customs, or practices he is applying to support his opinion.

    To the extent Plaintiff takes issue with a perceived lack of information or the conclusions Morrissey derived therefrom, Plaintiff may thoroughly cross-examine him at trial.

    However, Morrissey not only references the protocols and textbooks that he relies upon to support his opinions, but also his experience in emergency medical services when dealing with “situations where scene safety or patient presentation was quickly evolving.” Therefore, Morrissey’s opinion that “changes in patient status were promptly identified, assessed, and appropriately addressed” is sufficiently supported. So too is Morrissey’s opinion that “the Code was appropriately called after 35 minutes, when the emergency crews were unable to gain return of spontaneous circulation, and only after consulting with the hospital-based emergency physician.”

    Held

    The Court granted in part and denied in part Plaintiff’s motion to exclude the opinions of Jim Morrisey.

    Key Takeaway

    Morrissey’s opinions are based on his extensive knowledge and experience in the field of emergency medical services and the data, documents, and information he was provided regarding the Vanlandingham incident. However, the Plaintiff was left with little or no way to test Morrissey’s conclusions against any of the guidelines or factors involved in a Daubert analysis or to otherwise determine their reliability.

    Case Details:

    Case Caption: Vanlandingham V. City of Oklahoma City
    Docket Number: 5:22cv209
    Court Name: United States District Court, Oklahoma Western
    Order Date: March 18, 2026
  • Ophthalmology Expert’s Future Treatment Opinion Admitted

    Ophthalmology Expert’s Future Treatment Opinion Admitted

    This case arises from a trip and fall Plaintiff, Vivian Conerly, experienced on June 27, 2022 in the Hobby Lobby store in Hattiesburg, Mississippi. As she entered the store’s vestibule and rounded a display table, her shin struck a metal cart, and she fell face first onto the store’s concrete floor.

    Plaintiffs designated Dr. Jaime Jiménez as an expert. Jiménez is expected to testify that Conerly’s fall at Hobby Lobby caused the tributary branch retinal vein occlusion (“BRVO”) in her left eye and that she will require retinal injections as future treatment for this condition.

    However, Hobby Lobby sought to exclude his causation opinion on the grounds that it is unreliable because his opinion is based on facts he did not ask, examine, or otherwise determine from his treatment of Conerly.

    Ophthalmology Expert Witness

    Dr. Jaime Jiménez-Agosto is a board-certified ophthalmic surgeon. He is also fellowship-trained in vitreoretinal surgery. He has performed over fifteen thousand vitrectomies and more than fifty thousand retinal procedures.

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

    Discussion by the Court

    A. Causation Opinion

    Hobby Lobby asserted that Jiménez’s opinion is unreliable because Jiménez admitted that he does not know whether Conerly performed a Valsalva maneuver and instead relies on the assumption that she did because he personally holds his breath when he falls.

    Having reviewed the record evidence, the Court found that Jiménez’s opinion that the fall caused Conerly’s tributary BRVO is not based on assumptions or ipse dixit. Instead, Jiménez reviewed Conerly’s history; he reviewed her deposition and noted that after the fall she immediately complained of pain in her eye and exhibited symptoms consistent with a tributary BRVO; he personally examined her and ran tests that showed the retinal swelling had gotten worse; and, most importantly, he watched the video that showed her falling rapidly and hitting the ground with the left side of her face, which arguably could be better evidence than Conerly’s own recollection. These are the types of records, documents and materials commonly relied on by medical experts.

    Hobby Lobby is asking the Court to assign significance to Jiménez’s “lack of factual knowledge” based on unestablished supposition of what is required for a tributary BRVO to occur. The record is not clear—could hitting one’s eye with significant force be enough? Would only compressing the abdominal area be enough? Without knowing exactly what is required, it is further unclear whether Conerly performing a “Valsalva maneuver” is even necessary. Similarly, as for Jiménez’s not knowing what delta-v force occurred presupposes that there must be a specific delta-v force experienced before a tributary BRVO can occur. Given the state of the record, the Court found that these are issues to be addressed on cross-examination.

    B. Future Treatment Opinion

    Moreover, Hobby Lobby sought to exclude any opinion regarding future treatment on the grounds that it is too speculative.

    Jiménez is one of Conerly’s treating physicians. He has testified about the healing process of a tributary BRVO—that it must be monitored and that treatment for swelling is provided when needed. With BRVO treatment, “you stretch it out as much as you can, but it’s very frequent to have relapses.”

    He treated Conerly on a regular basis throughout 2025. Basically, his ongoing evaluations provided him with additional clinical observations and data to refine his opinions.

    Therefore, the Court found that Jiménez’s opinion as a treating physician regarding future medical treatment was admissible.

    Held

    The Court denied Defendant’s motion to exclude or limit the testimony of Dr. Jaime Jiménez.

    Key Takeaway

    An expert may base an opinion on facts or data in the case that the expert has been made aware of or personally observed. As a general rule, questions relating to the bases and sources of an expert’s opinion affect the weight to be assigned to that opinion rather than its admissibility and should be left for the jury’s consideration.

    Case Details:

    Case Caption: Conerly V. Hobby Lobby Stores, Inc.
    Docket Number: 2:24cv118
    Court Name: United States District Court, Mississippi Southern
    Order Date: March 20, 2026
  • Emergency Medicine Expert Was Not Allowed to Opine on Sedation

    Emergency Medicine Expert Was Not Allowed to Opine on Sedation

    This litigation stems from the death of Charles Lamar Vanlandingham in September of 2019. Plaintiff alleged that Vanlandingham suffered a medical episode with seizure activity in the early morning hours of September 15, 2019, and Vanlandingham’s girlfriend called 911. According to Plaintiff, Vanlandingham started to improve in the time it took EMS to arrive. Following the seizure activity, Vanlandingham had apparently transitioned to a “postictal state” that can cause confusion.

    Although Vanlandingham was initially compliant with EMS upon their arrival, Plaintiff alleged that “EMS providers tried to force Vanlandingham onto their medical cot,” and when Vanlandingham did not comply, “[EMT] Tuttle ultimately tackled Vanlandingham onto the medical cot.”

    Once members of the Oklahoma City Fire Department arrived, Plaintiff alleged that the Firefighters used their body weight to pin Vanlandingham in the prone position for approximately three minutes before Oklahoma City Police Officer Brandon Lee arrived. Officer Lee then put handcuffs on Vanlandingham—still in the prone position—and placed his knee across Vanlandingham’s back.

    Plaintiff alleged that Vanlandingham was in this position, handcuffed, for approximately four minutes, during which time “no one checked Vanlandingham’s vitals or advocated for a position change despite Vanlandingham’s clear signs of respiratory distress.” “Without knowing Mr. Vanlandingham’s vitals and without performing any kind of medical assessment,” EMT Tuttle then administered midazolam (a sedative), and Vanlandingham went limp. CPR efforts were unsuccessful, and Vanlandingham died at the scene.

    Plaintiff’s claims are against Defendants City of Oklahoma City, Officer Brandon Lee, and American Medical Response Ambulance Service, Inc. (AMRAS). During discovery, AMRAS disclosed an expert report prepared by Molly A. Furin, M.D., M.S., who is board certified in both Emergency Medicine and Emergency Medical Services.

    In the present motion, Plaintiff contended that Furin’s offered opinions should be excluded under Fed. R. Evid. 702.

    Emergency Medicine Expert Witness

    Molly Ann Furin is board-certified in both Emergency Medicine and Emergency Medical Services (EMS) and has obtained a Master of Science in Disaster Medicine and Management.

    She has worked at a level 1 trauma center for the past 17 years as well as community Emergency Departments.

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

    Discussion by the Court

    I. Timeliness of Furin’s Supplement

    Furin supplemented her expert report on May 20, 2025. In it, Furin did not expand the opinions listed in her initial report, but she did provide supplemental explanation of her education and experience in the emergency medicine field. Plaintiff contended that Furin’s supplement is untimely under Fed. R. Civ. P. 26(e)(2).

    Furin issued her supplemental report. However, Rule 26(a)(3) also refers to the deadline to file deposition designations, which has yet to expire. Accordingly, the Court found that Furin’s supplement of May 20, 2025, is timely under Rule 26(e)(2).

    II. Daubert Motion

    • Paramedic Tuttle and EMT Barnes performed an appropriate rapid assessment of Vanlandingham upon arrival, including checking blood glucose, and could not proceed with further evaluation and treatment because it became unsafe to do so. Evaluating for scene safety is one of the first skills taught in Emergency Medical Services, and the crew appropriately called for additional resources in a timely manner. Physical restraint of Vanlandingham was necessary at the time in order to prevent harm or injury to himself or crew members.
    • Upon the arrival of OCFD personnel, including Paramedic Morton, care was correctly transitioned to Paramedic Morton.
    • Paramedic Tuttle assisted the OCFD by drawing up and administering midazolam IM as requested. Sedation was paramount in order to further evaluate and treat Vanlandingham. Midazolam is a benzodiazepine, utilized for both sedation and treatment of seizures, and when administered intramuscularly takes a minimum of several minutes to take effect. Given the very brief time interval after administration, the midazolam had no causative role in Vanlandingham’s subsequent cardiac arrest.
    • When Vanlandingham sustained cardiac arrest, he was efficiently treated with high quality [Advanced Cardiovascular Life Support] care.

    Analysis

    First, the Court found that Furin’s initial report failed to clearly identify the basis for her opinions or explain how certain standards or her experience lead to the conclusions reached. Furin did not identify how her experience in the emergency medicine field led to her specific opinions.

    Next, Furin’s supplemental expert report did little to expand on the basis for her four opinions. Rather, Furin focuses on her qualifications to issue opinions regarding emergency medicine.

    Furin has largely failed—even after supplementing her report—to provide a basis for her opinions. Furin’s experience in emergency medicine, standing alone, is not sufficient to support her opinion that EMS “could not proceed with further evaluation because it became unsafe to do so.” Apart from explaining her experience in emergency medicine and providing examples of transitions of care, Furin’s supplemental report does not sufficiently explain how her experience (or knowledge of the industry standard) led her to opine that the transition of care in this case was “correct.”

    Next, Furin’s supplement did not provide a basis for her opinion that “sedation was paramount in order to further evaluate and treat Vanlandingham.”

    Although Furin stated that she “reviewed the patient care reports and documents provided to me, and is qualified to opine as to the quality of care provided when Vanlandingham sustained cardiac arrest,” Furin failed to provide any basis or reasoning for her opinion that the care provided to Vanlandingham was efficient and high quality.

    A portion of Furin’s third opinion was admissible under Rule 702 and Daubert because Furin has provided a sufficient basis for it. Furin can opine that—given her firsthand knowledge and experience with the administration and onset of midazolam—the midazolam could not have taken effect before Vanlandingham’s cardiac arrest.

    Held

    The Court granted in part and denied in part Plaintiff’s motion to exclude the opinions of Dr. Molly Furin.

    Key Takeaway

    It is fundamental that, if the basis for an expert’s opinions is to be tested for reliability, that basis must be identified in some fashion. Absent some identification of the basis for the expert opinion, there is little or no way to test it against any of the guidelines or factors involved in a Daubert analysis or to otherwise determine its reliability.

    Case Details:

    Case Caption: Vanlandingham V. City of Oklahoma City
    Docket Number: 5:22cv209
    Court Name: United States District Court, Oklahoma Western
    Order Date: March 18, 2026
  • Nursing Expert’s Infection Preventionist Testimony Excluded

    Nursing Expert’s Infection Preventionist Testimony Excluded

    Plaintiffs Elizabeth Combs, Thomas Johnston, Kimberly Herechberger and Michelle Boltz brought religious discrimination claims against their former employer PeaceHealth for failure to accommodate their religious beliefs in opposition to COVID-19 vaccination.

    In addition to bringing a religious discrimination claim, Boltz brought a disability discrimination claim against PeaceHealth for failure to accommodate her disability under the ADA and Oregon law.

    Defendant filed a motion to strike the testimony of Plaintiffs’ expert witness, Rose Walker Patterson, because she is “unqualified to render the opinions in her reports” and because her opinions are unreliable and irrelevant.

    Nursing Expert Witness

    Rose Walker Patterson is a Registered Nurse with a master’s degree in nursing administration—not epidemiology, virology, or infectious disease—who earned a certificate in infection control and prevention from the Certification Board of Infection Control and Epidemiology.

    From April 2017 through October 2022, Patterson worked as the Infection Preventionist and Employee Health nurse for Sky Lakes Medical Center (“SLMC”), a small, rural hospital in Klamath Falls, Oregon. Patterson was part of a committee that developed a “playbook planning for the pandemic” with which she was “heavily involved.” 

    Want to know more about the challenges Rose Walker-Patterson has faced? Get the full details with our Challenge Study report.

    Discussion by the Court

    A. Patterson is Qualified to Offer Infection Preventionist Testimony

    PeaceHealth contended that Patterson is not qualified to offer expert testimony because she lacked relevant education, training, and experience.

    Patterson is not a medical doctor and has no advanced education or training in epidemiology or in infectious diseases or any other medical field. Further, she has no research experience or publications related to COVID-19. And she has never taught at a college or university.

    Patterson, however, testified that in her role as nurse infection preventionist, she helped develop the weekly testing program at SLMC for employees with approved accommodations.

    Accordingly, the Court concluded that although Patterson is not qualified to offer scientific or medical opinion, she is qualified to offer expert testimony based on her knowledge and experience as a nurse infection preventionist at SLMC during the pandemic.

    B. Patterson’s Opinions are not Reliable

    First, Patterson’s opinions are not based on sufficient facts or data because (1) she based her opinions on an incorrect understanding of the Oregon Health Authority (“OHA”) Rule requiring all Oregon healthcare providers and staff to either be fully vaccinated against COVID-19 by September 30, 2021, absent medical or religious exception, or to “undergo COVID-19 testing at least weekly” and (2) she provided no documentation or data to support the work she claims to have done at SLMC.

    Patterson also provided no documentation for the program she claimed to have developed or implemented, and she provided no data about the clinical variables or outcomes of that program.

    The Court concluded that Patterson’s testimony is not based on sufficient facts and data because Patterson’s opinions rely on her misunderstanding of the OHA Rule and because Patterson failed to provide any underlying documentation or data to support her testimony.

    Second, Patterson’s opinions are not reliable because, in addition to failing to provide documentation and data, she also did not use reliable principles and methods to produce her opinions. In fact, Patterson did not produce her opinions at all.

    The Court concluded that Patterson did not conduct her own research, she did not undertake an independent analysis of the facts and data, and she did not author significant parts of her own Reports. Patterson’s opinions not only lacked factual basis; they also are not the product of reliable principles and methods.

    2. Patterson’s Opinions are not Relevant

    Even if Patterson’s testimony were reliable, it is not relevant. Patterson lacked the relevant facts and data to compare SLMC to PeaceHealth. Patterson testified generally about the differences between the two healthcare employers.

    She also testified that she lacked the relevant facts and data to compare PeaceHealth to SLMC. Importantly, the undue hardship standard at issue requires that an employer, when making an accommodation decision, consider the facts before them at the time the decision is made.

    Held

    The Court granted the Defendant’s motion to strike the testimony of Rose Walker-Patterson.

    Key Takeaway

    Recalling facts, data, and policy from memory without underlying documentation or data is insufficient to support expert testimony. Basically, Patterson’s testimony is neither reliable nor relevant. Patterson’s testimony is not based on sufficient facts or data, is not the product of reliable principles and methods, and failed to reflect a reliable application of the principles and methods to the facts of the case.

    Case Details:

    Case Caption: Combs V. Peacehealth
    Docket Number: 6:23cv1486
    Court Name: United States District Court for the District of Oregon
    Order Date: March 17, 2026
  • Fire Investigation Expert’s Specific Ignition-Source Opinion Excluded

    Fire Investigation Expert’s Specific Ignition-Source Opinion Excluded

    This subrogation action arises from a fire that occurred on April 10, 2022, involving a dump truck owned by Boggs Transport, Inc. (“Boggs”) and insured by Plaintiff Amerisure Insurance Company (“Amerisure”).

    The fire began in a parked dump truck identified as Truck No. 863 at Boggs’s facility in Pageland, South Carolina, and spread to four adjacent trucks, resulting in damage to five vehicles. At the time of the fire, Truck No. 863 had been upfitted with a tarping system manufactured and installed by Defendant and Third-Party Plaintiff Ox Bodies, Inc. (“Ox Bodies”). Amerisure, as subrogee of Boggs, initiated this action asserting claims against Ox Bodies arising from the alleged origin and cause of the fire. Ox Bodies denied liability and disputed both the location of the fire’s origin and the mechanism by which the fire ignited.

    In support of its claims, Amerisure designated two expert witnesses. Kenny A. McClure, P.E., M.S.M.E., CFEI, is offered as an expert in fire origin. McClure opined that the fire originated along the driver’s side of Truck No. 863, in the area of the battery compartment and associated electrical components mounted along the frame rail. Kevin R. Davis, P.E., is offered as an expert in fire causation. Davis opined that the fire was caused by an electrical failure associated with components of the tarping system, including a relay or controller installed as part of the Ox Bodies upfit.

    Ox Bodies filed a motion to exclude the testimony of both of Amerisure’s experts pursuant to Federal Rule of Evidence 702.

    Fire Investigation Expert Witnesses

    Kenny A. McClure, P.E., M.S.M.E., CFEI holds an Associate of Applied Science in mechanical engineering technology, a Bachelor of Science in engineering technology, a Master of Science in mechanical engineering, and designations as a licensed professional engineer, a certified fire explosion investigator, a certified fire vehicle investigator, and a certified fire and explosion investigator.

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

    Kevin Ray Davis, P.E. holds a Bachelor of Science in Electrical Engineering, is a licensed professional engineer, and maintains professional certifications in fire and explosion investigation and vehicle fire investigation. He has also worked for more than fifteen years as a consulting engineer investigating fires and electrical failures.

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

    Discussion by the Court

    A. Kenny McClure

    1. Reliability of the Origin Opinion

    Defendant primarily argued that McClure’s testimony is unreliable because his defined origin area is allegedly inconsistent with Defendant’s expert’s electrical arcing theory.

    Defendant framed the issue as a logical dilemma: if McClure’s origin area excluded the arcing location identified by Defendant’s expert, then McClure allegedly failed to consider an obvious alternative ignition source. Conversely, Defendant argued that if McClure’s origin area included that location, the opinion is unnecessary because both parties’ experts would be describing the same origin area. The Court did not find this argument persuasive because it conflates the geographic scope of an origin determination with the identification of a specific ignition source.

    To begin with, McClure is offered as an origin expert, not a causation expert. His opinions concerned the location of the fire’s origin within Truck No. 863, not the specific mechanism of ignition. That distinction frames the Court’s Rule 702 analysis.

    Fire investigators commonly identify an area of origin rather than a single ignition point when the available physical evidence does not permit greater precision. McClure applied this methodology here, concluding that the fire originated “along the driver’s side of Truck 863 in the area where the battery compartment, conductors, and electrical components are mounted along the frame rail.” That conclusion was based on his examination of burn patterns, fire dynamics, and electrical artifacts observed during the investigation. The record reflected that McClure employed the systematic fire-investigation methodology described in NFPA 921. Ox Bodies did not challenge the reliability of that methodology itself. Accordingly, the Court concluded that McClure’s origin analysis rests on a reliable investigative methodology consistent with Rule 702.

    2. Defendant’s Relay-Knowledge Argument

    Ox Bodies also argued that McClure’s opinion is speculative because he did not account for the post-fire location or condition of certain tarping-system relays.

    The Court concluded that this argument improperly conflates origin analysis with ignition-source or causation analysis.

    Under NFPA 921’s scientific method, investigators commonly determine the fire’s area of origin before identifying the specific ignition source. An investigator’s inability to determine the precise ignition mechanism does not invalidate the origin determination so long as the origin analysis is based on observed fire patterns, electrical artifacts, and other physical evidence.

    Here, McClure’s testimony concerns the area where the fire began, not the precise electrical component that initiated it. Defendant’s criticisms regarding relay locations, therefore, go to the weight of the testimony rather than its admissibility.

    3. Helpfulness to the Jury

    Ox Bodies also contended that McClure’s origin opinion is so broad that it amounts to common knowledge and is unhelpful to the jury. The Court disagreed. Although the identified origin area is not confined to a single component, the opinion rests on specialized interpretation of burn patterns, electrical artifacts, and fire dynamics beyond the experience of lay jurors. Interpreting burn patterns, electrical damage, arc mapping artifacts, and other indicators of fire progression requires specialized training and experience. Jurors lack the technical background to interpret such evidence reliably without expert assistance.

    Accordingly, the Court found that McClure’s origin opinions are grounded in accepted fire-investigation principles and satisfy Rule 702.

    Kevin Davis

    1. Reliability of Davis’ Methodology

    Ox Bodies first argued that Davis’ opinions violated accepted fire-investigation methodology because he did not determine ignition temperature, quantify the duration of any electrical fault, or conduct testing to replicate the proposed ignition mechanism.

    The Court agreed that portions of Davis’ analysis lack sufficient methodological support. Davis did not perform testing to confirm that the specific relay installed on Truck No. 863 could produce sufficient heat to ignite surrounding materials. Nor did he quantify the ignition temperature or duration necessary to produce ignition under the conditions present in the vehicle. Davis also relied in part on exemplar relay testing and recall information involving different relay configurations and applications.

    Here, the record does not contain sufficient evidence connecting the exemplar relay testing or recall materials to the specific relay installed in Truck No. 863. Without testing, analysis, or other evidence showing that the relay in question was capable of generating sufficient heat to ignite the surrounding materials under the conditions present in the truck, the Court concluded that the methodology supporting Davis’ specific ignition-source opinion is insufficient under Rule 702.

    2. Application of the Methodology to the Facts

    The Court nevertheless found that Davis’ testimony is not wholly inadmissible. Davis’s report also included engineering analysis concerning the truck’s electrical system, including the condition of the wiring harness, the lack of circuit protection in portions of the tarp-system wiring, and the potential for energized conductors to create ignition sources within the electrical system.

    These opinions are grounded in Davis’s inspection of the physical evidence and his application of electrical engineering principles to it. Such testimony may assist the jury in understanding the electrical mechanisms that could have produced a fire in the relevant portion of the vehicle.

    Accordingly, Davis may testify regarding electrical fire mechanisms, wiring damage, circuit protection, and the potential for energized conductors to act as ignition sources within the electrical system of Truck No. 863. However, Davis may not opine that a specific relay or tarping-system component installed on Truck No. 863 was the ignition source of the fire.

    This limited exclusion reflects the Court’s obligation under Rule 702 to ensure that expert testimony rests on a reliable foundation while permitting otherwise admissible technical testimony that may assist the trier of fact.

    To the extent Davis discussed the circuit breaker during his deposition testimony, the Court found that those statements elaborate on the electrical-fault theory disclosed in his report and are not a new expert opinion requiring exclusion under Rule 26.

    Held

    • The Court denied Defendant and Third-Party Plaintiff Ox Bodies, Inc.’s motion to exclude the testimony of Kenny A. McClure, P.E., M.S.M.E., CFEI.
    • The Court granted in part and denied in part Defendant and Third-Party Plaintiff Ox Bodies, Inc.’s motion to exclude the testimony of K.R. Davis, P.E. 

    Key Takeaway

    Even assuming McClure’s origin area overlaps with the location proposed by Defendant’s expert, the testimony remains relevant and helpful because McClure explains the fire patterns, burn damage, and electrical artifacts that confine the fire’s origin to a particular structural portion of the vehicle. Such analysis assists the jury in understanding the physical evidence and does not become inadmissible simply because the parties’ experts may partially overlap in their conclusions.

    Case Details:

    Case Caption: American Insurance Company V. Ox Bodies, Inc
    Docket Number: 4:23cv2445
    Court Name: United States District Court, South Carolina
    Order Date: March 17, 2026
  • Marketing Expert Was Allowed to Opine on Trademark Dilution

    Marketing Expert Was Allowed to Opine on Trademark Dilution

    Plaintiffs Hyundai Motor Company and Hyundai Motor America, Inc. (collectively “Hyundai Motor” or “Plaintiffs”) are one of the largest automobile manufacturers worldwide, with vehicle sales in over 150 countries.

    Defendant Hyundai Technology is a manufacturer and seller of consumer electronics products including tablets, laptop computers/notebooks, desktop computers, monitors, digital storage, cell phones, and accessories.

    The Plaintiffs filed a trademark infringement suit against the Defendants for “using” the Hyundai name to sell their technology products.

    Defendants offered Mark Keegan‘s testimony to refute Plaintiffs’ allegations that Defendants’ conduct dilutes Plaintiffs’ HYUNDAI Mark. Plaintiffs filed a motion in limine to exclude the testimony of Keegan.

    Marketing Expert Witness

    Mark Thomas Keegan has over 23 years of experience conducting consumer research, including being deposed and testifying at trial. Keegan earned his juris doctorate degree from Brooklyn Law School, has certifications in marketing knowledge and principles, and has completed post-graduate programs addressing market research processes.

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

    Discussion by the Court

    Keegan concluded that Plaintiffs’ allegations of dilution by tarnishment with respect to Defendant Hyundai Technology’s product user reviews do not “materially impact relevant consumer perceptions of Hyundai Motor, and as such, do not substantively impact the marketplace in which Hyundai Motor operates.” Keegan’s opinion relied on a study he conducted involving 850 participants identified as “likely purchasers of the Defendants’ products” based on their prior technology purchases.

    Keegan stated that he designed his survey in accordance with a combination of guiding principles, including survey research conducted for litigation purposes, relevant treatises in the field, including those from the American Bar Association, and industry leaders in market research.

    Plaintiffs argued that Keegan’s survey failed to employ well-established or reliable methodologies and did not rely on a representative sample because, among other things, 41.8% of respondents were age 61 or older.

    The Court, however, found that Keegan’s opinions are relevant as they address “consumer impressions of the Hyundai Motor brand,” which is a central issue to the underlying case. The arguments made by Plaintiffs are all issues to be decided by the jury based on credibility and weight.

    Held

    The Court denied Plaintiffs’ motion in limine to exclude the testimony of Mark Keegan.

    Key Takeaway

    Expert opinion testimony is relevant if the knowledge underlying it has a valid connection to the pertinent inquiry. And it is reliable if the knowledge underlying it has a reliable basis in the knowledge and experience of the relevant discipline.

    Case Details:

    Case Caption: Hyundai Motor Company V. Hyundai Technology Group, Inc.
    Docket Number: 8:23cv1709
    Court Name: United States District Court, California Central
    Order Date: March 06, 2026