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  • Fine Arts Expert’s Testimony on Fair Market Value Limited

    Fine Arts Expert’s Testimony on Fair Market Value Limited

    In 2018, John Hock completed a 53-foot steel sculpture, Prometheus III. The work was displayed in Franconia Sculpture Park, an institution Hock co-founded and his then-employer. In 2019, Franconia terminated Hock, and he agreed to remove Prometheus III from the park. By late 2023, he had not done so, and Franconia, believing the sculpture was abandoned, disassembled it and sold it for scrap. Hock sued for violations of the Visual Artists Rights Act, a federal statute that protects artists’ “moral rights,” including the right not to have certain artworks destroyed. He also raised several state-law claims.

    Hock’s expert witness is Rachael Blackburn Cozad. Franconia filed a motion to exclude Cozad’s testimony.

    Fine Arts Expert Witness

    Rachael Blackburn Cozad has over thirty years’ experience in the fine arts field. She has a Bachelor of Arts degree in art history from Texas Christian University, a Master of Arts degree in art history from California State University, Los Angeles, and Uniform Standards of Professional Appraisal Practice (“USPAP”) certification.

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

    Discussion by the Court

    Cozad examined Prometheus III’s fair market value with two methods. The first method was the sales comparison approach, which sets the value by analyzing sales of the artist’s similar artworks. Cozad found only one comparable piece, the Prometheus III maquette, which sold for $12,00 in 2001.

    The second method was the cost approach, which estimates the price to recreate or replace an artwork. Cozad received information about Prometheus III’s “materials, dimensions, labor etc.” from Hock and then consulted two “fabricators and foundries” for estimates.

    Ultimately, she concluded that Prometheus III’s fair market value was $1,300,000, which was a number in the middle of the two fabricators’ estimates, increased by 30% to account for Hock’s time and expertise.
    Cozad included an “Accompanying Budget Note,” which identified the market value of two large public sculptures to show that a valuation around $1,000,000 was “not unusual.” Lastly, Cozad opined that Prometheus III “qualifies as a work of ‘stature’” under VARA.

    Analysis

    1. Sales Comparison Approach

    Cozad did not rely on the sales comparison approach to generate the sculpture’s fair market value. The report described a “combined approach,” but it determined the final value with reference to the cost approach alone. As a result, the sales comparison portions was excluded because they will not help the jury understand the evidence or determine a fact in issue.

    Because she did not use the sales comparison approach in calculating market value and testified to its deficiencies in this circumstance, testimony about that method would not help the trier of fact understand the evidence or determine material facts.

    Cozad testified that scaling was “a very common practice . . . especially . . . when artists make things that are similar but in different sizes,” and that it is “generally an acceptable approach for appraisers to use when there’s a shortage of good comparable sales data.” The Court found this statement insufficient to show reliable principles and methods. To start, there is the commonsense objection that an artwork’s value is unlikely to increase in proportion to its size.

    Cozad cited no case or other authority where an appraiser used the scaling approach. Cozad explained why she judged Prometheus III against only one work: Large sculptures like this one tend to be site-specific, so they are rarely publicly traded; they are costly to relocate; and they can suffer damage during disassembly as part of the moving process. She considered Hock’s other sales but concluded they were poor comparators.

    2. Cost Approach Valuation

    Franconia sought to exclude the cost approach valuation portion for two reasons. First, it argued that replacement cost will often not reasonably approximate fair market value. However, the cost approach is an approved
    method under USPAP guidelines. Cozad testified cogently about why she adopted it—namely, the other approved methods were less applicable.

    Second, Franconia argued that Cozad inappropriately relied on and repeated hearsay from other experts, the individual fabricators who estimated the cost to replace Prometheus III. She testified that certified professional art appraisers “commonly communicate with art fabricators as part of their appraisals” and “reasonably rely on information obtained from art fabricators in forming their appraisal opinions,” especially when applying the cost approach to large steel sculptures. The problem is not reasonable reliance but that her opinion is not truly independent of the fabricators’ conclusions. For these reasons, Cozad’s cost approach valuation was not admissible and therefore excluded by the Court.

    3. Accompanying Budget Note

    Franconia sought to exclude the “Accompanying Budget Note,” which provided the commission and appraisal prices of two other large public sculptures. The Court agreed. The fact that other sculptures are worth a million dollars is material to Prometheus III’s value only if those pieces are sufficiently similar to Prometheus III.

    4. Work of Stature

    Franconia sought to exclude Cozad’s opinion that Prometheus III qualifies as having “stature” under VARA. Other courts have explained that an artist’s general reputation, past works, and community recognition are relevant to the subject artwork’s stature. As a result, the Court refused to exclude this portion.

    Held

    The Court granted in part and denied in part Franconia’s motion to exclude certain testimony of Plaintiff’s expert Rachael Blackburn Cozad.

    Key Takeaway

    Even if Rule 703 were no barrier to admissibility, Cozad’s opinion would run afoul of Rule 403, because the probative value of her contribution—the arithmetic—would be substantially outweighed by a danger of prejudice from considering the fabricators’ hearsay valuations.

    Case Details:

    Case Caption: Hock V. Franconia Sculpture Park 
    Docket Number: 0:24cv3546
    Court Name: United States District Court, Minnesota
    Order Date: June 02, 2026
  • Mechanical Engineering Expert Not Allowed to Opine on Blender Warnings

    Mechanical Engineering Expert Not Allowed to Opine on Blender Warnings

    SharkNinja manufactured the Ninja Professional Plus Blender, model BL610. Cody Ford received the blender as a gift at her bridal shower in February 2023. The blender was in a box and after opening the box, Ford removed the “top pulp tray” which, according to the design, rests on top of the wrapped pitcher that contains the blade assembly. Thinking she was going to grab the pitcher, Ford then reached into the box where she grabbed the blade assembly instead and “severely lacerated her left pinky finger.”

    As a result, Ford sued SharkNinja. In support of her claims, Ford
    hired an engineering expert, Mingxi Zheng. SharkNinja filed a motion to exclude Zheng.

    Mechanical Engineering Expert Witness

    Mingxi Zheng is a licensed professional mechanical engineer in California with a specialty in “metallurgy, fracture mechanics, and failure analysis.”

    She received degrees in materials science and engineering and has worked as a materials scientist and mechanical engineer at various reputable institutions.

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

    Discussion by the Court

    According to Zheng, the blender was defectively designed because it lacked protective covers on a new blade assembly and the warnings included with the blender were insufficient and did not comply with the proper standard for product safety signs and labels.

    SharkNinja contended that Zheng’s design defect opinion should be
    excluded. The Court agreed.

    Zheng concluded that blade guards could have been included without, for example, identifying consumers’ expectations for the packaging of such products, considering the cost of the guards themselves, or accounting for the effects of increasing the time or manpower needed to manufacture and package blenders with blade guards. At most, she offered a cursory comparison to a product that has little in common with the product here beyond that both feature, in substantially different forms, a sharp edge. Zheng did not explain how the scientific method, failure analysis, or root cause analysis methodology helped reach this conclusion.

    SharkNinja also contended that Zheng is not qualified to offer expert testimony regarding the adequacy of the warnings. Ford failed to meet her burden to establish Zheng’s qualifications regarding this opinion because Zheng has no expertise in human factors or product warnings.

    Held

    The Court grant SharkNinja’s motion to exclude Ford’s expert, Mingxi Zheng.

    Key Takeaway

    Courts often require experience or expertise in “human factors engineering” or product warnings to opine on the adequacy of warnings. Zheng has no expertise in human factors or product warnings.

    Case Details:

    Case Caption: Ford V. Sharkninja Operating LLC
    Docket Number: 8:25cv245
    Court Name: United States District Court for the Middle District of Florida, Tampa Division
    Order Date: June 01, 2026
  • Product Safety Expert’s State-of-Mind Testimony Excluded

    Product Safety Expert’s State-of-Mind Testimony Excluded

    On November 10, 2022, Kenneth and Phyllis Zerr perished in a house fire. Plaintiffs—the Zerrs’ children and Kenneth Zerr’s estate—alleged that the fire was caused by a defective dehumidifier produced by Gree.

    In support of their defense, Defendants planned to use expert witnesses. On the origin of the fire, Defendants offered Todd Soong. On the potential electrical causes of the fire, Defendants offered Arash Hajjim. Lastly, on fire dynamics, patterns, and potential causes of the fire, Defendants offered Carlos Fernandez-Pello. Together, the experts purport to establish that the cause of the fire remains undeterminable. Plaintiffs sought the exclusion of three defense experts.

    Plaintiffs have also produced Roy Deppa as an expert on the topic of Consumer Product Safety Commission (CPSC) regulations and procedures for the purpose of establishing that Defendants failed to timely report dangerous defects in their dehumidifiers. Defendants sought the exclusion of Deppa.

    Fire Investigation Expert Witness

    James Todd Soong is a certified fire investigator (CFI) by the International Association of Arson Investigators (IAAI) and a certified fire and explosion investigator (CFEI) by the National Association of Fire Investigators (NAFI). He has in excess of 10 years of experience.

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

    Electrical Engineering Expert Witness

    Arash Hajjam is a forensic electrical engineer and has in excess of 15 years of experience.

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

    Thermodynamics Expert Witness

    Dr. Carlos A. Fernandez-Pello is a Distinguished Professor of the Graduate School in Mechanical Engineering, at the University of California, Berkeley, USA. His work involves applying fire thermodynamics and combustion principles to analyze various aspects of fire and combustion processes, ranging from laboratory-scale solid fuel combustion to wildland fire dynamics.

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

    Product Safety Expert Witness

    Roy W. Deppa has over 40 years of experience in product safety, including 27 years in various positions at the Consumer Product Safety Commission. This experience gave him extensive knowledge of the agency’s regulations, processes, and procedures, as well as industry standards.

    He is a registered Professional Engineer licensed in the State of Maryland.

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

    Discussion by the Court

    I. Todd Soong

    Defendants retained Soong to determine the origin of the fire and its potential causes. Plaintiffs argued that Soong’s opinions must be excluded because they are based on incomplete and inaccurate information and they are not the product of reliable principles and methods.

    A. Soong’s opinions on the origin and cause of the fire are admissible

    Soong followed the methods prescribed by NFPA 921 in determining that the fire originated in the home’s utility room and that the cause of the fire could not be definitively determined. He performed an inspection of the building, observing fire damage levels and patterns.

    Plaintiffs argued that Soong’s opinions are unreliable because he did not conduct his own testing; he uses “ambiguous words such as ‘possible,’ ‘may,’ and ‘can’”; and he developed his opinions with cherry-picked facts and confirmation bias.

    However, the Court found that Soong’s method of determining the origin and potential causes of the fire—relying on observations of physical evidence, scientific principles, experience, and the opinions of Defendants’ other expert witnesses—is consistent with NFPA 921 and sufficient to satisfy Rule 702.

    NFPA 921 advises that investigators should seek assistance when they “lack expertise to properly attribute meaning to a piece of data” and should utilize the “special talents or training” of other individuals in the fields of “electrical, heating and air conditioning, and other engineering fields” when needed. And NFPA 921 specifically instructs investigators to utilize words like “probable” and “possible” to denote the appropriate level of certainty.

    B. Soong’s opinion relating to spoliation is inadmissible

    Plaintiffs also argued that “Soong improperly claimed spoliation of evidence” under NFPA 921, which defines spoliation as “loss, destruction, or material alteration of an object or document that is evidence or potential evidence in a legal proceeding by one who has the responsibility for its preservation.”

    The Court found that Soong is not qualified to opine on whether anything he observed was a result of “spoliation” or some other cause. 

    II. Arash Hajjam

    Plaintiffs argued that Hajjam’s opinions must be excluded because he failed to follow the methodology outlined in NFPA 921.

    However, Hajjam followed NFPA 921’s prescribed method for fire cause determination. His report relied on two joint site examinations, two lab inspections, the expert reports of the other fire investigation experts proffered in this case, and several other photographs and documents, including NFPA 921.  

    Based on his observations of the scene and analysis of the artifacts, Hajjam identified three potential causes of the fire—the dehumidifier, the branch circuit wiring in the ceiling, and a nearby light fixture—and examined each in a laboratory. Hajjam then evaluated each potential cause and ultimately concluded that “given the extensive damage and the presence of missing artifacts, multiple potential ignition sources remain, preventing a definitive conclusion regarding the exact ignition source of the fire.” The Court found that Plaintiffs’ arguments regarding the sufficiency of Hajjam’s testing and his alleged consideration of improper evidence are insufficient, in this case, to undermine the admissibility of his testimony.

    III. Carlos Fernandez-Pello

    Defendants offered Fernandez-Pello to discuss “potential causes and contributing factors to the fire and the possibility of the subject Dehumidifier and other potential ignition sources causing the fire.” Specifically, he was expected to provide testimony that the cause of the fire is indeterminate as per NFPA 921.

    Fernandez-Pello’s opinions followed NFPA 921’s prescribed method for fire cause determination. Moreover, Fernandez-Pello discussed the fire patterns surrounding the dehumidifier, the results of the dehumidifier tests, and generated computer simulations.

    Plaintiffs argued that Fernandez-Pello’s opinions should be excluded because (1) he failed to consider the presence of additional fuel loads in the vicinity of the dehumidifier; and (2) he failed to conduct testing regarding internal arcing in the dehumidifier. Those arguments fail. Although Fernandez-Pello initially testified that he was not aware of several plastic buckets near the dehumidifier, he later submitted errata indicating that he had reviewed photographs of the buckets, “concluded that the buckets didn’t burn, only melted,” and “thus, there was no need to investigate the issue anymore.”

    Such inconsistency in Fernandez-Pello’s testimony on different occasions may be relevant to his credibility as a witness, but it does not undermine its admissibility altogether. And given Fernandez-Pello’s position that the dehumidifier could not have been the cause of the fire, regardless of how it ignited, the fact that he did not do additional testing to determine whether there was internal arcing did not undermine the credibility of his opinion.

    IV. Roy Deppa

    Defendants argued that Deppa’s testimony should be excluded because (1) Deppa is unqualified, as a professional engineer, to opine on the interpretation of federal regulations or Defendants’ state of mind; (2) his opinions concerning the process by which companies issue recalls and Defendants’ state of mind lack scientific methodology; (3) his opinions improperly relate only to punitive damages; and (4) his opinions, even if admissible, are barred under Federal Rule of Evidence 403, as his “interpretation of federal regulations and Defendants’ obligations under them would run the risk of creating a danger of overriding the Court’s jury instructions on the same” and his opinions concerning the severity of Defendants’ failure to recall risked interfering with the jury’s duty to evaluate liability.

    Analysis

    As an initial matter, the Court found that Deppa’s proposed testimony relating to Defendants’ state of mind is improper. Moreover, Deppa may not offer his opinion about whether Defendants’ conduct violated applicable regulations because the the law is clear that expert witnesses may not opine as to whether a party violated a given regulation.

    The Court also shared Defendants’ concern that Deppa’s report included qualitative characterizations of Defendants’ conduct unconnected to any specific industry standard, and that such characterizations invade the province of the jury, who will be tasked with determining if Defendants’ conduct “showed complete indifference to or conscious disregard for the safety of others.”

    In spite of that, the Court concluded that Deppa, based on his professional experience, is qualified and permitted to testify about (1) the industry standards relating to CPSC recalls, including references to relevant regulations, so long as he does not opine on whether Defendants’ conduct actually violated any regulations; and (2) Defendants’ conduct in response to the product defect that Plaintiffs allege is at the heart of this case, including the effects of those actions on the availability of the defective product.

    Held

    • The Court denied Plaintiffs’ motions to exclude the testimony of Arash Hajjam and Carlos Fernandez-Pello.
    • The Court granted in part Plaintiffs’ motion to exclude the testimony of Todd Song.
    • The Court granted in part Defendants’ motion to exclude the testimony of Roy Deppa.

    Key Takeaway

    Expert testimony on “the intent, motives, or states of mind of corporations, regulatory agencies and others have no basis in any relevant body of knowledge or expertise.” Thus, Deppa may not opine on what Defendants, or individuals employed by Defendants, thought or about their motivations. 

    Please refer to the blogs previously published about this case:

    Fire Investigation Expert Was Allowed to Opine on UL Listing

    Insurance Expert Not Allowed to Opine on the Actual Cash Value of the Home

    Case Details:

    Case Caption: Hillman V. Gree USA, Inc.
    Docket Number: 4:23cv830
    Court Name: United States District Court, Missouri Eastern
    Order Date: May 23, 2026
  • Psychology Expert’s Testimony on Trauma Victims Limited

    Psychology Expert’s Testimony on Trauma Victims Limited

    Plaintiff Colleen Nix alleged that Kevin Keiner, a New Mexico State Police Officer, sexually assaulted her while she was intoxicated and asleep.

    Nix sought to introduce the testimony of both Elizabeth Thomson and Andrea Taylor. New Mexico Department of Public Safety and New Mexico State Police requested the Court to bar Thomson and Taylor from testifying.

    Law Enforcement Expert Witness

    Elizabeth Thomson is a retired law enforcement professional with more than two decades of experience. From 1999 to 2017, Thomson served as an officer with the Albuquerque Police Department (“APD”), retiring at the rank of sergeant. She held a variety of investigative and supervisory roles at APD.

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

    Psychology Expert Witness

    Andrea Brooke Taylor is a licensed clinician and retired law enforcement captain with over 20 years of experience in trauma-focused mental-health counseling. She has a Masters Degree in Clinical Mental Health Counseling and a Masters Degree in Forensic Psychology. She specializes in Post Traumatic Stress Disorder (“PTSD”), Complex Post-Traumatic Stress Disorder (“CPTSD”), trauma assessment, and the psychological impact of sexual violence.

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

    Discussion by the Court

    Elizabeth Thomson

    Thomson is qualified based on her twenty years of law enforcement experience and extensive training. For instance, she may testify regarding patterns in sexual assault cases due to her training, field experience, and six years of specialized service on a crisis intervention team. She may testify regarding police procedures based on her service as a homicide sergeant, where she developed and updated departmental policies and standard operating procedures.

    Defendants sought to limit Thomson’s testimony. First, they challenged her opinions regarding Nix’s and Keiner’s credibility as usurping the jury’s role. Specifically, they sought to preclude Thomson from testifying that Nix was truthful while Keiner was not, or from characterizing the parties’ statements as “consistent” or “inconsistent.”

    Nix contended that Thomson did not make credibility determinations but instead applied her investigative expertise to identify “consistencies and inconsistencies” in the parties’ statements. The Court is not persuaded. Even when framed in these terms, such testimony effectively invites the jury to conclude that accounts deemed “consistent” are credible, while those labeled “inconsistent” are not.

    Next, Defendants sought to preclude Thomson from testifying that the evidence is consistent with a nonconsensual sexual encounter. The Court declined to limit such testimony. Expert testimony offering “general and conditional opinions” about whether behavior aligns with patterns observed in sexual abuse cases is permissible.

    Finally, Defendants moved to preclude Thomson from testifying that Keiner was acting under “color of law” because such testimony would usurp the role of the jury. In this case, the Court found that Thomson’s proposed testimony—that Keiner was acting under “color of law” when he encountered Nix—did not usurp the jury’s fact-finding role. Jurors are unlikely to understand how police officers are trained to recognize whether they are acting under “color of law.”

    Andrea Taylor

    A. Taylor’s methodology is reliable under 702

    First, Keiner argued that Taylor’s methodology is unreliable under Rule 702. Taylor’s opinions are the product of a reliable methodology. She employed a multi-method approach to screen Nix for PTSD and CPTSD by administering seven diagnostic questionnaires and conducting two clinical interviews.

    The Court found Keiner’s arguments to the contrary unpersuasive. First, he argued that Taylor’s opinions are unreliable because she failed to use a Clinician-Administered PTSD Scale (“CAPS-5”) to diagnose Nix with PTSD “despite acknowledging CAPS-5 as the gold standard.” As discussed above, Taylor’s methodology is reliable because it is grounded in her professional experience. 

    Next, Keiner challenged Taylor’s conclusion that Nix has Complex PTSD because “Complex PTSD is not a distinct diagnosis under the DSM-5.” Taylor sufficiently explained each step of her analysis and the basis for her conclusions. The Court’s inquiry ends there.

    Keiner also argued that Taylor’s opinions are unreliable because she failed to perform any differential etiology or rule out alternative causes of Plaintiff’s PTSD symptoms. The Court disagreed. Differential etiology is simply one method of assessing causation in the medical context. Keiner’s assertion that Rule 702 “requires an expert to engage in a reasoned differential etiology” is unsupported.  Regardless, Taylor accounts for alternative causes of Nix’s symptoms and distinguishes between Nix’s baseline functioning and her post-incident decline. Taylor acknowledged Nix’s pre-existing anxiety and extensive trauma history, including childhood abuse and prior violence.

    B. Taylor’s methodology is based on sufficient facts and data under 702

    Keiner next argued that Taylor’s opinions are not based on sufficient facts or data under Rule 702.

    Taylor relied on sufficient facts and data here. She concluded, “to a reasonable degree of psychological certainty,” that the alleged sexual assault caused Nix’s PTSD and CPTSD symptoms. Taylor based that opinion on Nix’s “test results, symptom presentation, personal narrative, and trauma chronology,” and testified that her methodology was “standard” and grounded in her professional experience. The Court is satisfied that Taylor did not selectively “cherry pick” favorable facts but relied on the type of information reasonably considered by mental-health professionals conducting trauma assessments.

    Keiner claimed that Taylor improperly relied on Nix’s self-report without “independently verifying” the information through medical or therapy records, the Sexual Assault Nurse Examiner (“SANE”) exam, or other “objective” evidence. But the Court does not “require every expert to undertake an independent evaluation of the entire record to determine what he or she did or did not need to consider.” Taylor testified that it is “standard” to rely on self-reported symptoms to form diagnostic opinions—that is all the Court requires under 702.

    C. Portions of Taylor’s testimony are unhelpful under 702

    Finally, Keiner argued that portions of Taylor’s proposed testimony are not “helpful” under Rule 702. Specifically, Keiner challenged Taylor’s assertions that Nix was truthful in reporting the alleged assault; trauma victims “have no gain” in being untruthful; and gaps in Nix’s deposition testimony can be explained by dissociation or freezing.

    Taylor may not vouch for Nix’s truthfulness at trial. Taylor may not testify, for example, that Nix was truthful in reporting the incident or that inconsistencies in Nix’s account resulted from a trauma response. Those determinations remain within the exclusive province of the jury.  The Court also barred Taylor from opining that trauma victims “have no gain” in being untruthful—such testimony crosses the line into improper bolstering by suggesting that the jury should accept Nix’s account.

    This limitation did not preclude Taylor from testifying about the experiences and behaviors of trauma victims generally.

    Held

    • The Court granted in part and denied in part Defendants’ motion to exclude Elizabeth Thomson.
    • The Court granted in part and denied in part Defendants’ motion to exclude Andrea Taylor.

    Key Takeaway

    Expert testimony offering “general and conditional opinions” regarding patterns commonly observed in sexual-abuse victims is admissible. Taylor may testify, for example, that sexual-assault victims may experience memory lapses, dissociation, and freezing responses. Such testimony assists jury members in evaluating Nix’s testimony without telling them what to believe—an important distinction under 702.

    Case Details:

    Case Caption: Nix V. New Mexico Department Of Public Safety
    Docket Number: 1:24cv691
    Court Name: United States District Court, New Mexico
    Order Date: May 27, 2026
  • Mechanical Engineering Expert Was Allowed to Opine on the Effects of Air Bubbles

    Mechanical Engineering Expert Was Allowed to Opine on the Effects of Air Bubbles

    Plaintiff Darin Edwin Pape brought this products liability action against Defendant Bodum USA, Inc. (“Bodum”), alleging that defects in Bodum’s coffee press caused him injury when the press’ glass shattered and hot water spilled onto his body.

    Plaintiff’s expert Mingxi Zheng opined that a combination of (i) a manufacturing defect that allowed air bubbles to form within the French Press’s glass carafe, (ii) a design defect that allowed for direct contact between a protruding steel wire in the plunger and the French Press’ glass carafe, and (iii) thermal and mechanical stress from normal use of the French Press led the product to “ultimately fail.” Bodum filed a motion to exclude Zheng’s expert testimony.

    Mechanical Engineering Expert Witness

    Mingxi Zheng is a licensed professional mechanical engineer in California with a specialty in “metallurgy, fracture mechanics, and failure analysis.”

    She received degrees in materials science and engineering and has worked as a materials scientist and mechanical engineer at various reputable institutions.

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

    Discussion by the Court

    Bodum primarily contended that Zheng’s conclusions are speculative because she has not tested her hypotheses or provided adequate support from the record.

    a. Zheng’s Expert Testimony Is Reliable

    First, Bodum claimed that Zheng provided no support for her conclusion that thermal stress contributed to the fracture. While Bodum may disagree with the strength or even the accuracy of Zheng’s conclusion about thermal stress, the Court determined that her opinion is based on factual evidence observed in the subject carafe as well as her own scientific expertise and research. Zheng’s opinion about thermal stress as a contributing factor is supported by actual observations that she has made of the French Press combined with research on common signs of thermal stress in glass. 

    Second, Bodum contested Zheng’s air bubble theory, once again arguing that it was not rooted in adequate testing or fact. The Court is sympathetic to Bodum’s criticisms of the gaps in Zheng’s air bubble theory, but it ultimately found that her opinion is not so “speculative or conjectural or based on assumptions that are so unrealistic and contradictory as to suggest bad faith or to be in essence an apples and oranges comparison.”

    Third, Bodum took issue with Zheng’s expert opinion about the plunger, namely that the mechanical stress from the plunger as well as the protruding metal coil in the plunger contributed to the fracture. 

    Although the Court found Zheng’s plunger conclusions to be especially weak, it once again is constrained to conclude that they meet the relatively low bar for admissibility.

    Although the Court found Zheng’s plunger conclusions especially weak, it was once again required to conclude that they met the relatively low bar for admissibility.

    Finally, the Court declined to exclude Zheng’s expert testimony because of her apparent “failure to rule out obvious alternative causes of the fracture.” An expert need not rule out every alternative cause in forming an opinion.

    c. Zheng’s Expert Testimony Will Assist the Jury

    Given the complexities of glass fractography, Zheng’s expert testimony about the effects of thermal stress, air bubbles, and mechanical stress can help explain “how and why the French Press was defective” and caused Pape’s injury.

    As to the matters of defect and causation, this Court is satisfied that her opinions “will assist the trier of fact” in making a decision in this case.

    Held

    The Court denied Bodum’s motion to exclude the testimony of Mingxi Zheng.

    Key Takeaway

    The Court excused Zheng’s lack of testing in this case because she examined the French Press; observed crack patterns, crack lines, and air bubbles that could conceivably support her conclusion about the combined effects of thermal and mechanical stress on defective glass; and cited scientific research to demonstrate that her theories are not so novel and unprecedented that real-world testing is required. 

    Case Details:

    Case Caption: Pape V. Bodum USA, Inc.
    Docket Number: 1:23cv8401
    Court Name: United States District Court, New York Southern
    Order Date: March 27, 2026
  • Accounting Expert Not Allowed to Opine on Transition Period

    Accounting Expert Not Allowed to Opine on Transition Period

    Robert Webster allegedly owed fiduciary duties, including duties of loyalty and honesty, to his employer, CellMark. He was also subject to contractual obligations restricting him from competing with CellMark or soliciting its customers or employees on behalf of himself or others. According to CellMark, Webster began breaching these duties in 2023 after deciding to leave the company and allegedly taking steps to move certain customers away from CellMark.

    CellMark claimed that, before Webster’s departure in June 2024, he had either diverted or prepared to divert several customers to CellMark’s competitors. The company further alleged that Göran Sohl, Fortex Americas, LLC, and DRC Industries, Inc., a supplier that later became a competitor, assisted or encouraged Webster’s conduct because they stood to benefit from the resulting business opportunities. CellMark also alleged that these entities were aware of Webster’s fiduciary and contractual obligations but proceeded despite those obligations.

    Based on these allegations, CellMark brought several claims, including breach of fiduciary duty, breach of restrictive covenants, violations of the Kentucky Uniform Trade Secrets Act and the Defend Trade Secrets Act, and civil conspiracy.

    CellMark retained Jay R. Cunningham to offer expert testimony on its damages. Defendant Rob Webster and the Fortex Defendants (Fortex Americas, LLC, Dinah Bowman, and Göran Sohl) filed respective motions to exclude the testimony of testimony of Cunningham.

    Accounting Expert Witness

    Jay Ryan Cunningham has more than 20 years of accounting and finance experience as a consultant in litigation, investigative and other business dispute matters.

    He has managed or assisted on engagements providing advisory services to clients in a wide variety of disputes and performing a variety of damage analyses. He has also managed or assisted in special investigations related to accounting restatements, fraud, and other inappropriate business practices.

    Cunningham is a graduate of Murray State University, Kentucky, with a B.S.B. degree in accounting and an M.P.Acc. degree.

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

    Discussion by the Court

    A. Cunningham’s disgorgement analysis must be excluded because it is unhelpful

    CellMark believed it was entitled to disgorgement as a remedy for Webster’s alleged misconduct. To quantify this remedy, CellMark had Cunningham analyze the amount Webster should allegedly disgorge. To do so, Cunningham added up figures from a CellMark payroll spreadsheet.

    Webster argued that Cunningham’s disgorgement analysis was merely “basic math” and should be excluded because it was not beyond the ken of common knowledge.

    The parties agreed that Cunningham performed basic math to analyze the amount of disgorgement allegedly available. The Court therefore concluded that Cunningham’s opinions on disgorgement “should be excluded on such grounds.”

    B. Cunningham’s overall lost-profits methodology is not fatally flawed

    Webster contended that Cunningham failed to follow “a reliable methodology” because Cunningham “did not consider the other factors that could have caused CellMark’s losses, making his opinion unreliable and inadmissible.” The Fortex Defendants primarily contended that Cunningham’s methodology relied too much on CellMark’s “management’s belief, not on an analysis of CellMark’s” financial data, and also failed to consider “whether industry trends or market conditions could have impacted sales.”

    While these may be reasons to criticize Cunningham’s analysis, they are not valid grounds for excluding all of Cunningham’s lost-profits testimony.

    It is also true that Cunningham adopted a particularly rosy view of how things would have supposedly turned out for CellMark had the alleged misconduct not occurred—and did so based primarily on information provided to him by CellMark. But Cunningham is entitled to that optimistic perspective so long as it is based on evidence and not clearly contradicted by the evidence.

    The Court cannot say that Cunningham’s entire lost-profits analysis is so “clearly contradicted” by the evidence in this case that it must be excluded merely because he believed that CellMark’s historical performance would have continued undisturbed but for the alleged conduct of Webster and the Fortex Defendants.

    In sum, Cunningham’s overall methodology is not so defective or unreliable as to render all of his testimony about lost profits completely excludable.

    C. Cunningham’s invention of an unsupported seven-month “transition period” is improper and should be excluded

    While Cunningham’s overall methodology is not fatally flawed, one element of his analysis is. Webster and the Fortex Defendants asserted that when Cunningham tacked on a seven-month “transition period” to the damages period for each CellMark customer, he impermissibly relied on baseless speculation.

    When Cunningham’s report discussed the time period he used to analyze lost profits, he noted that he “included an additional seven-month transition period” for every customer because he believed Webster’s year-long non-compete period would, in turn, cause an additional “reasonable delay” before Webster could successfully solicit customers. Cunningham’s choice of a seven-month period, he asserted, was “based upon an estimated average time to solicit and onboard customers, as well as order and receive associated product.”

    But Cunningham cited no evidence in support of this “estimated average”—he did not, for example, consult industry data to establish a range for how long it might reasonably take a player in the market to develop a relationship with a customer currently being serviced by another supplier or how long it would generally take to build up an inventory to service such clients.

    Cunningham’s seven-month transition period is the product of bare speculation. Cunningham himself tacitly acknowledged this: When questioned at his deposition about his basis for the transition period, Cunningham testified that the “seven-month period is an assumption,” that he did not “have data that suggests . . . how long does it take to get that customer,” and that there was no other data point that he could point to that would back up his choice to assume a seven-month transition period—or any other quantified time period, for that matter.

    D. The Court will not exclude Cunningham’s opinions on lost profits related to Camelot / Integrity

    Webster and the Fortex Defendants next argued that Cunningham’s analysis of lost profits relating to Camelot / Integrity is fatally defective because it is likewise too speculative.

    CellMark responded by citing documentary evidence indicating that CellMark sold products to Camelot before its bankruptcy and sold products to Integrity in 2024 through a former Camelot representative that Integrity retained after Camelot was acquired by Integrity, thereby laying a foundation for Cunningham’s assumption of CellMark’s continued sales.

    This is a close call. On the one hand, it seems tenuous to assume a company that acquired a CellMark customer after its bankruptcy would continue to purchase products from CellMark as though nothing had changed. Indeed, the document Cunningham cites for the proposition that CellMark expected future business with Integrity via Webster plainly did not reflect any firm purchasing commitment from Integrity. On the other hand, there is evidence that Integrity continued to purchase products from CellMark via the relationship Webster fostered with Camelot’s representative (whom Integrity kept on board) after Integrity acquired Camelot and that there was an ongoing relationship with CellMark. And there is evidence that Fortex made large volumes of sales shortly thereafter. Bearing in mind that there is thumb on the scale in favor of admitting expert testimony, the Court is reluctant to exclude Cunningham’s testimony about lost profits relating to Camelot / Integrity.

    Therefore, the Court will not exclude Cunningham’s testimony relating to Camelot / Integrity.

    E. No other theories that would justify partial exclusion

    Webster and the Fortex Defendants raised a series of additional arguments for partial exclusion of Cunningham’s opinions.

    First, the Defendants took issue with Cunningham’s unique damages period for Multi-Color Corporation. There is a factual dispute about whether CellMark would, in fact, have renewed its exclusivity agreement with Asia Pulp and Paper and continued on as an exclusive supplier for Multi-Color Corporation’s needs for months after Webster’s departure. Cunningham is therefore allowed to assume that CellMark would have done so. But the Defendants are equally allowed to contest the veracity of the facts underlying his assumption and to vigorously cross-examine Cunningham to determine the effect on his analysis if the jury does not credit CellMark’s evidence.

    Second, Webster raised the issue of inflation, suggesting that Cunningham’s assumption of a 3.5% yearly price increase benefitting CellMark was unsupportable in light of “market data showing an industry in decline.” The Court concluded that the issue of whether Cunningham’s assumptions about inflation and market conditions were too optimistic is better addressed through cross-examination than outright exclusion.

    Third, Webster contended that “Cunningham attributes customer sales declines to Webster” even though “CellMark’s corporate representative admitted there is no evidence implicating Webster.” Of course, this entire dispute is about whether Webster diverted business away from CellMark. Arguments rooted in factual disputes over what the evidence does and does not show and the related effects on an expert’s output are properly resolved through cross-examination—not wholesale exclusion.

    Finally, Webster contended that Cunningham went beyond the scope of his expertise by offering certain statements about “industry customs and standards” in the paper industry. The Court did not find this argument convincing.

    The Court concluded that Cunningham should be allowed to testify about what he understands are paper industry norms and how they inform his analysis of CellMark’s lost profits.

    Held

    • The Court granted in part and denied in part Webster’s motion to exclude the testimony of Jay Cunningham.
    • The Court granted in part and denied in part the Fortex Defendants’ motion to exclude the testimony of Jay Cunningham.

    Key Takeaway

    Expert testimony “should be excluded if it is based on ‘unrealistic assumptions’” or “unsupported speculation.” Cunningham’s arbitrary seven-month “transition period” relied on both. This is a prime example of the sort of baseless testimony that courts may properly exclude. Cunningham may not testify at trial as to any “transition period” following the term of Webster’s non-compete period.

    Please refer to the blog previously published about this case:

    Accounting Experts’ Testimony on Exclusivity Agreement Limited

    Case Details:

    Case Caption: Cellmark, Inc. V. Webster
    Docket Number: 2:24cv181
    Court Name: United States District Court, Kentucky Eastern
    Order Date: May 29, 2026
  • Anesthesiology Expert Allowed to Opine on Effects of Hypoxia

    Anesthesiology Expert Allowed to Opine on Effects of Hypoxia

    In this method of execution case, Plaintiff Jeffery Lee challenged the
    Alabama Department of Corrections’ nitrogen hypoxia protocol. Execution by forced inhalation of nitrogen gas deprives an inmate of oxygen until he suffocates to death.

    Lee filed a motion to exclude the testimony of State’s expert, Dr. Joseph F. Antognini.

    Anesthesiology Expert Witness

    Dr. Joseph F. Antognini is a medical doctor and board-certified anesthesiologist with significant clinical experience. His subspecialty is in “neuroanesthesia,” which he described as “the practice of anesthesia applied to patients who are having neurological surgery of some sort.” He has published extensively, and his research centers “on anesthetic mechanisms, specifically related to where anesthetics produce unconsciousness, amnesia, and immobility.” He has also held multiple teaching positions over the course of his career and was a tenured professor of both anesthesiology and pain medicine as well as neurobiology, physiology, and behavior at the University of California, Davis.

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

    Discussion by the Court

    Qualification

    Lee argued that this case, which “concerns respiratory physiology” and “the effects on the body of forced inhalation of nitrogen gas,” fell outside Antognini’s expertise because he is an anesthesiologist and conceded in his deposition that the case does not involve the administration of anesthesia agents and that nitrogen is not an anesthetic gas.

    Antognini is not a pulmonologist, but he is an anesthesiologist, and he testified at length about the diverse areas of medicine that specialization requires knowledge of, including respiratory physiology. The breadth of his training is demonstrated by the fact that Antognini has more than a decade’s experience as a professor not just of anesthesiology, but also of pain medicine, neurobiology, and physiology.

    Accordingly, the Court disagreed with Lee’s position that there is a fundamental mismatch between Antognini’s training and the effects of nitrogen hypoxia generally.

    So even if Antognini’s opinions regarding the effects of oxygen deprivation were limited to his general experience as an anesthesiologist, that alone would not furnish a basis for excluding him. To the extent there is a gap between Antognini’s area of expertise and the subject matter at issue here, that gap goes to the weight of his testimony, not its admissibility.

    Reliability

    Lee also argued that Antognini’s opinions are not reliable because the data he relied on “differ in significant respects from the execution context.”

    Lee took issue with several of the studies on which Antognini relied: (1) the reports of workplace accidents, because they do not indicate whether the workers who perished “suffered in any way”; (2) the case reports of inert gas suicides, as many of the suicides had “severe underlying medical problems,” which Antognini conceded at deposition could produce “a different physiological response to hypoxia”; (3) the high-altitude “pilot studies,” since Antognini admitted that the difference in barometric pressure is material; (4) the Ernsting study, as the participants in that study, unlike condemned inmates, “were instructed to fully exhale and then hyperventilate nitrogen gas”; and (5) a fifty-year-old study on the euthanasia of dogs with nitrogen gas because it is outdated and the American Veterinary Medical Association now “recommends against the use of nitrogen as a method to euthanize dogs.”

    The Court held that these purported issues do not render Antognini’s opinions wholly unreliable. To take the industrial-accident reports as an example, although it is unclear from those reports whether the workers who succumbed to nitrogen gas suffered, the reports do represent some of the very limited data that exist regarding involuntary inert gas asphyxiations.

    To be sure, the studies on which Antognini relied are not perfect matches. However, the same is true of many of the studies on which Lee’s experts rely, which are generally taken from the clinical setting. Ultimately, the issues that Lee identified with Antognini’s studies go to the persuasiveness of his opinions, not their admissibility.

    Held

    The Court denied Lee’s motion to exclude the testimony of Dr. Joseph Antognini.

    Key Takeaway

    Expertise is not exclusively conferred by degrees or specializations in particular specialties or subspecialties. Experts may be qualified in various ways. While scientific training or education may provide possible means to qualify, experience in a field may offer another path to expert status.

    Case Details:

    Case Caption: Lee V. Lovelace
    Docket Number: 2:25cv680
    Court Name: United States District Court, Alabama Middle
    Order Date: May 28, 2026

  • Trucking Expert Not Allowed to Opine on the Trailer Door

    Trucking Expert Not Allowed to Opine on the Trailer Door

    This dispute arises from an incident that occurred on February 6, 2021, in which Plaintiff Lee James Barley was injured when he fell while loading his belongings into a trailer.

    Defendants ArcBest II, Inc. and Old Dominion Freight Line, Inc. filed motions to exclude the opinions of Mark Respass, Jeffrey Marksthaler, and Michael Freeman.

    Trucking Expert Witness

    Mark Respass has 40 years of training and experience in the commercial trucking industry, including fleet safety management, risk management, driver recruiting and training, accident investigation.

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

    Engineering Expert Witness

    Jeffrey R. Marksthaler is a licensed Professional Engineer with 35 years of experience in heavy manufacturing facilities and production management, manufacturing process and quality control, mechanical and chemical testing, accreditation, failure analysis and risk assessment for processes, materials, components, consumer products, food product, and consumer goods.

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

    Forensic Medicine Expert Witness

    Michael David Freeman is credentialed as a Fellow of the Royal College of Pathologists (UK), Fellow of the Faculty of Forensic and Legal Medicine (FFLM) of the Royal College of Physicians (UK) and member of the British Association in Forensic Medicine.

    He has also taught courses in forensic medicine, forensic epidemiology, and injury epidemiology at the Oregon Health and Science University School of Medicine and Maastricht University.

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

    Discussion by the Court

    I. Motion to Exclude Expert Opinions of Mark Respass

    To begin with, Defendants sought to exclude the opinions of Respass on the grounds that he lacked the requisite qualifications, expertise, or experience to render expert opinions regarding Old Dominion’s scheduled inspections and maintenance of the trailer door and strap or the applicable Federal Motor Carrier Safety Regulations (“FMCRs”) regarding annual inspections and maintenance.

    Respass made several findings including that the strap at issue was “badly worn and weakened” when the trailer was delivered to Plaintiff, the Old Dominion driver who delivered the trailer failed to notice that the strap was badly worn and weakened, and Old Dominion fell below a reasonable standard of care for a motor carrier by not maintaining the roll-up door’s mechanical components and the pull strap.

    However, Respass conceded that he did not have “expertise in pull straps” or in “determining what causes them to fail” or any expertise “in what fibers or materials were involved in this particular strap.” He also stated that he based his finding that the strap was “badly worn and weakened” when the trailer was delivered to Plaintiff on “common sense, that this is an old strap.” When asked to “put aside common sense” and to provide what “expertise he has in determining why this particular strap failed,” Respass stated that he “would not have any scientific expertise as to why it failed.”

    Accordingly, the Court concluded that Plaintiff has not established by a preponderance of the evidence that Respass’ opinions are based on adequate facts or data or on a reliable methodology. Plaintiff also has not established that Respass is qualified as an expert by his “knowledge, skills, experience, training, or education” or that his technical or other specialized knowledge will help the trier of fact.

    II. Motion to Exclude Expert Opinions of Jeffrey Marksthaler

    A. Marksthaler’s Initial Expert Report

    Defendants sought to exclude the opinions of Marksthaler contained in his initial expert report on the grounds that he lacked the requisite education, training, experience, and expertise to qualify as an expert in the testing and analysis of the door strap or operation, maintenance, repair, or inspection of commercial trailer doors, and he failed to apply reliable scientific principles and methodology to his analysis and instead relied on speculation and intuition.

    Marksthaler testified that he is a metallurgical engineer and his only education on woven materials involved a “very small amount” of a one-semester general materials undergraduate course. Marksthaler admitted that he “had no experience in what might cause fraying polyester or similar fibers or materials, such as a strap.”

    When asked for the source of Marksthaler’s information and opinion that fibers fray more easily when they are dirty, he responded that it was a video on YouTube regarding climbing rope rather than a scientific article or similar.

    B. Marksthaler’s Rebuttal Report

    In his rebuttal report Marksthaler opined that “immediately before failure, only a small section of the strap width remained.” At deposition, however, Marksthaler conceded that “he would have to think of a way” to scientifically determine when various sections of the strap failed.

    Marksthaler agreed at deposition that the idea of shock loading “occurred to [him]” before his first expert report, but he did not make any mention of shock loading in his initial report. He also agreed that none of the defense experts mentioned or discussed shock loading.

    Marksthaler conceded that he had the information to opine about shock loading before he produced his first report and the record reflects that defendants’ experts did not mention or discuss shock loading. Accordingly, the Court concludes that Marksthaler’s opinion regarding shock loading in his rebuttal report is precluded by Rule 26.

    The Court concluded that Plaintiff has not established by a preponderance of the evidence that Marksthaler’s opinions are based on adequate facts or data or on a reliable methodology.

    C. Motion to Strike Marksthaler’s Declaration

    Defendants filed a motion to strike Marksthaler’s declaration, which was submitted in support of Plaintiff’s response to Defendants’ motion to exclude, on the grounds that most of the declaration contradicted his deposition testimony, contained hearsay, and was not supported by the evidence.

    The Court granted Defendants’ motion to strike to the extent that it would disregard the portions of the declaration that contradicted Marksthaler’s deposition testimony, were not supported by the evidence, and/or did not contain admissible evidence.

    III. Motion to Exclude Expert Opinions of Michael Freeman, Ph.D.

    A. Freeman’s Qualifications

    Freeman acknowledged at deposition that he is an epidemiologist “with a focus on traffic crash related injuries,” not an engineer or a biomechanical engineer and he does not have a degree in engineering, biomechanical engineering, biomechanics, kinematics, or kinetics.

    Plaintiff also cited several cases in which courts have admitted Freeman as an expert, but these cases involved traffic accident reconstructions, a topic in which Freeman is well-versed.

    B. Reliable Principles and Methods

    On September 9, 2024, Adanty completed a report in which he opined that Plaintiff’s injuries are not consistent with him falling directly on to his elbows and that if the strap broke as Plaintiff reported, “he would not have fallen in a movement pattern that would result in his body landing on the left side of the ramp.”

    In his rebuttal report Freeman, however, stated that “absent video footage of the fall, there is no way to determine the dynamics of the fall, beyond the basic description” provided by Plaintiff at deposition where he stated that he fell backwards.

    When asked what biomechanical principles supported Freeman’s view that Plaintiff fell backwards off the ramp, Freeman responded that “it’s Plaintiff’s recollection. I don’t have a video to say what he says isn’t true.”

    The Court concluded that Plaintiff has not established by a preponderance of the evidence that Freeman is qualified to offer a rebuttal opinion on the biomechanical aspects of the incident at issue or that Freeman applied reliable principles and methods under Rule 702 or Daubert.

    C. Freeman’s Declaration

    Defendants also filed a motion to strike Freeman’s Declaration on the basis that it is contradicted by this deposition testimony, reports, and curriculum vitae. The Court granted Defendants’ motion to strike to the extent that it will disregard the portions of Freeman’s declaration that are contradicted by his deposition testimony, are not supported by the evidence, and/or do not contain admissible evidence.

    Held

    The Court granted Defendants’ motions to exclude the opinions of Mark Respass, Jeffrey Marksthaler, and Michael Freeman.

    Key Takeaway

    An expert may submit a rebuttal report if the evidence is intended solely to contradict or rebut evidence on the same subject matter identified by another party. Using a rebuttal report as a backdoor to introduce analysis that could have been included in the opening report is squarely foreclosed by Rule 26.

    Case Details:

    Case Caption: Barley, II V. Arcbest II, Inc.
    Docket Number: 3:22cv1921
    Court Name: United States District Court, Oregon
    Order Date: March 11, 2026
  • Accounting Experts’ Testimony on Exclusivity Agreement Limited

    Accounting Experts’ Testimony on Exclusivity Agreement Limited

    CellMark brought several claims against Dinah Bowman, Göran Sohl, and
    Fortex Americas, LLC (collectively the “Fortex Defendants”), as well as Rob Webster arising out of the unamicable end of Webster’s employment at CellMark in 2024.

    Plaintiff CellMark, Inc. retained an expert, Jay Cunningham, to show that it
    suffered various economic damages arising from its claims in this case.

    Webster retained Joshua Shilts to rebut Cunningham’s opinions, and the Fortex Defendants retained Robert Kester for the same purpose.

    CellMark filed a motion to exclude certain testimony from the Defendants’ rebuttal experts.

    Accounting Expert Witnesses

    Joshua James Shilts CPA,ASA, CFF/CGMA/ABV, CFE, has held roles with public accounting firms ranging in size from the “Big Four” to smaller regional and local firms, as well as large public organizations throughout Florida and New York.

    Shilts has provided expert testimony in commercial and family matters involving business valuation, economic damages, fraud, and other disciplines related to economics and accounting issues.

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

    Robert Breece Kester, CPA/ABV/CFF, specializes in the assessment of economic damages, business valuation, and accounting matters. He has provided consulting services related to businesses across a cross-section of industries, including but not limited to financial services, manufacturing, restaurants, retail, distribution, transportation, logistics, construction, professional services, and many other specialized industries.

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

    Discussion by the Court

    A. Shilts and Kester may not testify about any legal opinions.

    CellMark argued that Shilts’ and Kester’s reports are littered with legal opinions and that they must be prohibited from testifying as to those points at trial.

    Both Shilts’ report and Kester’s report contain conclusion sections that summarize their criticisms of Cunningham’s report.

    The conclusion sections of the Defendants’ reports veer into the realm of legal opinion by calling Cunningham’s opinion speculative, unreliable, and unsupported by sufficient data. Thus, the Court granted CellMark’s motion to exclude testimony from Shilts and Kester that invaded the province of the Court by stating legal opinions and invaded the province of the jury by telling it how it should weigh the evidence.

    B. Shilts and Kester may critique Cunningham’s reliance on assumptions regarding the exclusivity agreement, but they may not opine as to the ultimate truth of those assumptions.

    Next, CellMark argued that Shilts and Kester may not testify about whether Cunningham correctly assumed for his damages model that CellMark would have renewed an exclusivity agreement.

    Shilts and Kester both criticized Cunningham’s report for assuming that CellMark would have renewed its exclusivity agreement with Asia Pulp and Paper but for Webster’s failure to renew the agreement.

    While Shilts and Kester may critique Cunningham’s assumptions regarding the exclusivity agreement, they must avoid testifying about whether the agreement should have been renewed or whether it would have been renewed but for Webster’s conduct.

    Accordingly, the Court denied CellMark’s motion to the extent it mischaracterized the Defendants’ reports.

    But the Court granted the motion to the extent Shilts and Kester intended to testify that the evidence showed that the exclusivity agreement would not have been renewed in any event and to the extent they intended to testify that Cunningham’s opinions are not based on truthful or objective evidence.

    C. Similarly, Shilts may critique Cunningham’s reliance on assumptions about continued business with Duro-Last, but he may not opine as to the ultimate truth of those assumptions.

    Shilts’ report said that his “understanding is that Duro-Last wanted to consolidate suppliers” and that this could have reduced CellMark’s lost profits attributable to Duro-Last.

    Shilts made it clear that his testimony as a rebuttal expert will criticize Cunningham’s opinion on damages— nothing more.

    But the same concerns for the exclusivity agreement issue apply here. Shilts’ testimony must not state whether it is true that Duro-Last allegedly wished to consolidate suppliers or that Cunningham’s opinions are not supported by truthful or objective evidence.

    Accordingly, the Court denied CellMark’s motion to the extent it mischaracterized Shilts’ report. Shilts may critique the assumptions that Cunningham relied upon regarding the volume of business that CellMark would have continued to receive from Duro-Last. But the Court granted the motion to the extent Shilts intended to testify that the evidence showed that Duro-Last desired to consolidate suppliers and therefore would not have continued to place orders with CellMark.

    D. Shilts and Kester may testify about CellMark’s damages, including by providing quantified examples of how they believe Cunningham’s calculations overstate the potential damages.

    CellMark said that the Defendants’ experts should not be allowed to testify to the total amount of damages that CellMark suffered or what the damages period should be because it would be testimony on an undisclosed opinion and would mislead the jury and confuse the issues.

    Shilts and Kester did not provide a single, quantified total of CellMark’s damages in their reports, unlike Cunningham.

    Instead, their reports took a piecemeal approach to separately criticize various aspects of Cunningham’s model, and they pointed out instances where they believe Cunningham’s calculations have overstated the potential damages by a specific, quantified amount.

    Expert testimony by Shilts and Kester about CellMark’s damages clearly falls within the scope of rebuttal. The Defendants’ expert disclosures were properly made, and testimony consistent with their reports would help the jury understand any perceived problems with Cunningham’s opinions on damages. The lack of a total damages calculation is not a good reason to preemptively exclude such testimony when it was within the experts’ purview to use a piecemeal approach instead.

    The Court recognized that there is a potential for the jury to be confused by the ways in which Shilts and Kester might provide discrete quantified examples of how they believe Cunningham’s calculations overstate CellMark’s prospective damages. If properly explained, those quantified examples can be helpful to the jury in evaluating Cunningham’s opinions and calculations.

    E. Shilts may testify about the decline in the distilled spirits industry.

    Lastly, CellMark argued that Shilts may not testify about a decline in the
    distilled spirits industry to rebut Cunningham’s damages calculations.

    According to CellMark, Shilts’ testimony would unreasonably rely upon an online news article for which Shilts does not know the identity of the author. The news article summarized a variety of surveys and reports about alcohol consumption by Americans to suggest that it is on the decline.

    Whether news articles or reports are a reliable basis for an opinion depends on the context and the kind of expertise at issue.

    It is widely believed that the alcohol industry is on the decline in the United States generally, and Shilts offered testimony on this point to lay out a factor that he believed Cunningham should have considered.

    The Court is satisfied that the article contains the kinds of facts and data that business experts would rely upon, but Cellmark is free during trial to challenge Shilts about his knowledge of the article’s author and publisher.

    For now, the Court concludes that Shilts should be allowed to testify about the decline in the alcohol industry and the impact he believes that has on Cunningham’s opinions.

    Held

    The Court granted in part and denied in part CellMark’s motion to exclude certain opinions of Robert Kester and Joshua Shilts.

    Key Takeaway

    A rebuttal expert’s role is to contradict or rebut evidence on the same subject matter identified by another party’s expert disclosure. They have no burden to produce models or methods of their own; they need only attack those of the opposing experts.

    Case Details:

    Case Caption: Cellmark, Inc. V. Webster
    Docket Number: 2:24cv181
    Court Name: United States District Court, Kentucky Eastern
    Order Date: May 26, 2026
  • Insurance Expert Not Allowed to Opine on the Actual Cash Value of the Home

    Insurance Expert Not Allowed to Opine on the Actual Cash Value of the Home

    On November 10, 2022, Kenneth and Phyllis Zerr perished in a house fire. Plaintiffs—the Zerrs’ children and Kenneth Zerr’s estate—alleged that the fire was caused by a defective dehumidifier produced by Gree.

    Defendants sought to call an insurance adjuster, Steven Weitz, to testify as to the value of the home, and its contents, before and after the fire. Plaintiffs filed a motion to exclude his testimony.

    Insurance Expert Witness

    Steve Mark Weitz is a Licensed Independent Adjuster licensed in California with over 30 years of experience in analyzing loss claims, with a focus on residential fire losses.

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

    Discussion by the Court

    Plaintiffs did not challenge Weitz’s credentials. Rather, they argued that Weitz’s opinion should be excluded because he evaluated the “actual cash value” of the home and its contents, where Missouri law requires damages to be assessed using the “fair market value” of the property before and after the fire.

    The question before the Court, then, is whether Defendants have shown that that it is more likely than not that Weitz’s “replacement cost less depreciation” testimony would “help the trier of fact to determine” the property’s “fair market value.”

    Missouri Approved Jury Instruction (MAI) 16.02 defines “fair market value” as “the price that the property in question would bring when offered for sale by one willing but not obliged to sell it and when bought by one willing or desirous to purchase it but who is not compelled to do so.”

    It is the Defendants’ burden to show that Weitz’s testimony is more likely than not admissible under Rule 702. However, Defendants produced no statute, jury instruction, or case law suggesting that testimony about “replacement cost less depreciation” would help the jury determine “fair market value” as defined in MAI 16.02. Instead, they cited cases from distinctly different contexts, in which courts interpreted “actual cash value” as “fair market value,” not cases in which courts allowed parties to establish “fair market value” by presenting evidence of “replacement cost less depreciation,” as Defendants propose. Moreover, they made the specious claim that Weitz “employed the same standard” as MAI 16.02, citing two parts of his report that relate to his valuation of the contents of the Zerrs’ home, not the structure.

    Held

    The Court granted Plaintiffs’ motion to exclude the testimony of Steven Weitz.

    Key Takeaway

    Defendants have failed to establish the admissibility of Weitz’s testimony under Rule 702 by a preponderance of the evidence because mischaracterization of the expert’s report is not a strong foundation for an
    argument.

    Please refer to the blog previously published about this case:

    Fire Investigation Expert Was Allowed to Opine on UL Listing

    Case Details:

    Case Caption: Hillman V. Gree USA, Inc.
    Docket Number: 4:23cv830
    Court Name: United States District Court, Missouri Eastern
    Order Date: May 26, 2026