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  • Construction Expert’s Opinions on Typical Overhead and Profit Margins Admitted

    Construction Expert’s Opinions on Typical Overhead and Profit Margins Admitted

    This litigation arises from hail damage to a hotel owned by Defendants, Merryton Bossier, LLC, Grace Chiao, and Hui Ping Lee (collectively, “Merryton”) in Bossier City, Louisiana, in 2020.

    Merryton engaged Stonewater Roofing LTD. Co., LLC  to perform roof repairs, contingent upon insurance approval by Scottsdale Insurance Company (“Scottsdale”).

    After appraisers assessed the damage, Scottsdale refused to approve the work based on the estimates provided. The parties proceeded to mediation, and an amount of $1,500,000 was agreed upon. However, the parties never signed the mediation agreement, and Merryton later informed Stonewater that they would not proceed with the work. It is disputed exactly what work Stonewater performed. Following this, Stonewater filed suit, and Scottsdale filed a motion to enforce the settlement agreement, leading to the deposit of the $1,500,000 amount into the court registry. Stonewater now claims a right to those funds, while Merryton disputes it. Stonewater and Merryton both filed motions for summary judgment, and the Court ruled that a contract with a suspensive condition existed, but the question of whether that condition was fulfilled will be determined at trial.

    Merryton retained William J. Cowley (“Cowley”) as a rebuttal expert to critique the methodology, assumptions, and pricing analysis of Stonewater’s expert.

    Stonewater argued that Cowley’s testimony should be excluded, asserting that his testimony did not meet the requirements of Rules 401–403 and 702.

    Construction Expert Witness

    William Jeffrey Cowley  has 44 years of experience in the construction industry, including expertise in claims adjusting and roofing. 

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

    Discussion by the Court

    Stonewater argued that Cowley’s opinion regarding the typical overhead and profit being 10% each is unsupported by anything except Cowley’s subjective opinion. Stonewater also contended that Cowley’s reliance on national, generalized data failed to consider the specific circumstances of this case. Additionally, Stonewater argued that Merryton failed to timely provide a signed expert report in compliance with the Court’s Scheduling Order and Federal Rule of Civil Procedure 26, asserting that the signed version of Cowley’s report was produced only after the applicable deadline had passed.

    In a separate motion in limine, Stonewater again challenged Cowley’s testimony. The motion made several arguments identical to the Daubert motion, including arguments on Cowley offering legal conclusion.

    Analysis

    Cowley’s Qualifications

    Cowley’s qualifications are sufficient to offer opinions on the reasonableness of cost estimates and the methodology employed by Norrell. Stonewater does not contest these credentials, so the Court need not consider his qualifications in detail.

    Posture of the Issue: Limited Rebuttal Expert

    Because Cowley is not offering new opinions about the cost of repairs or liability but instead critiques the assumptions and conclusions of Stonewater’s expert, he is not required to generate an entirely new calculation for repair costs. Merryton contests liability, so it would be illogical for its expert to assume liability for purposes of preparing a competing cost estimate. Thus, the Court held that Cowley is not obligated to offer an independent repair costs estimate.

    Untimely Signed Report

    Plaintiff raised the procedural issue that Cowley’s report was not signed on time as required by Rule 26 and the Court’s Scheduling Order. Rule 26(a)(2)(B) requires that an expert submit a signed, written report.

    The Court must use the following factors to determine whether the failure to disclose was justified or harmless: “(1) the explanation for the failure to disclose; (2) the importance of the evidence; (3) the potential prejudice to the opposing party of admitting the evidence; and (4) the possibility of curing such prejudice by granting a continuance.”

    Here, Stonewater argues that Cowley’s expert report should be excluded because it was not signed by the deadline set forth in the Court’s Scheduling Order. The record reflected that although Cowley’s report was initially served without a signature, Cowley later executed the report, and a signed copy was provided to Stonewater. The contents of the report did not change, and Stonewater was fully apprised of Cowley’s opinions prior to delivery of the signed copy.

    The Court found that any failure to timely provide a signed report was harmless. First, the omission of the signature appears to have been a mere oversight, rather than an attempt to evade disclosure obligations. Second, Cowley’s testimony is important to Merryton’s rebuttal of the opposing expert’s cost analysis, so exclusion would be a disproportionate sanction given the nature of the deficiency. Third, Stonewater has not demonstrated prejudice arising from the lack of a timely signature, as it received the report itself on time, was aware of the substance of Cowley’s opinions, and had the opportunity to depose Cowley. Accordingly, the Court found that the initial failure to provide a signed expert report did not warrant exclusion under Rule 37(c).

    Cowley’s Critique of the $1,500,000 Figure

    Stonewater argued that Cowley offered an impermissible legal conclusion by stating that there is no contractual or other basis for using the $1,500,000 mediation amount as the price for the roofing work.

    The Court found that Cowley’s discussion of the $1,500,000 mediation amount fell within the proper scope of rebuttal expert testimony and did not constitute an impermissible legal conclusion.

    Cowley did not attempt to resolve whether the mediation agreement is legally enforceable or whether Stonewater is ultimately entitled to the insurance proceeds. Rather, he critiqued the opposing expert’s assumption that the mediation amount may be treated as a fixed contract price for purposes of calculating damages.

    The Discrepancy Between the Date of Loss and Pricing (2020 vs. 2025)

    Cowley’s use of the U.S. Department of Labor Statistics Producer Price Index to highlight price increases in non-residential roofing from 2020 to 2025 is a valid methodology for adjusting for inflation. Under Rule 703, experts may base their opinions on sources that other experts in their particular field would reasonably rely on. Stonewater argued that Cowley’s reliance on government statistics is improper because it is “broad, national data—without a bridge to the specific job or loss date ….”

    According to the Court, Cowley is not required to produce an independent cost estimate, and he did not use the Producer Price Index to calculate damages or to offer a substitute cost estimate.

    As for whether the Producer Price Index is the best source for this data, it can be explored on cross examination. Any lack of project-specificity goes to the weight of Cowley’s testimony, not its admissibility.

    Scope of Rebuttal

    The opposing expert’s damages analysis depends on the pricing data he selected, and Cowley’s testimony directly challenges the accuracy of those inputs. Stonewater’s attempt to draw a distinction between critiquing the opposing expert’s “formula” and critiquing the pricing inputs used within that formula is an artificial one. Pricing assumptions are an integral component of the methodology itself, and challenging those assumptions is a proper means of rebutting the resulting conclusions.

    Overhead and Profit

    Stonewater contended that Cowley’s statement that 10% overhead and 10% profit is the industry standard should be excluded because Cowley did not produce independent research supporting this statement. However, the Court found that Cowley was not required to produce research to support this statement.

    With 44 years of experience, Cowley is qualified to testify about standard industry practices in roofing, including typical overhead and profit margins.

    Cowley’s Opinion Will Assist the Trier of Fact

    Stonewater argued that Cowley’s opinions will not assist the trier of fact and amount to nothing more than subjective commentary supported only by his credentials.

    The Court disagreed. Cowley’s testimony assisted the trier of fact by explaining industry practices and by identifying potential deficiencies in the assumptions and inputs underlying Norrell’s damages analysis. These are matters that are not within the common knowledge of a lay juror. Moreover, evaluating the reasonableness of pricing assumptions, inflation adjustments, and customary overhead and profit margins in the commercial roofing industry requires specialized knowledge. Cowley’s opinions provided context and explanation that will help the jury in evaluating Norrell’s conclusions. Any weaknesses in Cowley’s opinions may be explored through cross examination. 

    Motion in Limine

    The Court has already determined that Cowley’s testimony is admissible under Rule 702. The majority of the arguments raised in Stonewater’s motion in limine merely repackaged those same Daubert challenges under the guise of Rules 401, 402, and 403.

    However, Stonewater did raise an additional relevance argument. Stonewater contended that Cowley’s opinions are irrelevant under Rules 401 and 402 because Cowley’s assertion that 2020 pricing inputs should have been used would, if applied within Norrell’s model, produce a profit margin higher than the 49% margin Cowley already characterizes as excessive. See Record Document 153 at 5. According to Stonewater, this alleged inconsistency rendered Cowley’s testimony irrelevant and therefore inadmissible.

    The Court found that this argument is unpersuasive. Stonewater’s reasoning rests on the assumption that the $1,500,000 mediation amount constitutes a fixed and binding contract price. This is a premise that Cowley did not accept and that remains disputed in this litigation. Framing Cowley’s rebuttal opinions as internally inconsistent requires acceptance of the assumptions Cowley challenges. Because that premise is disputed, this argument did not undermine the relevance of Cowley’s testimony.

    Held

    The Court denied Stonewater’s Daubert motion to exclude the testimony of William J. Cowley and motion in limine to exclude or limit the opinions and testimony of William J. Cowley.

    Key Takeaway

    In this context, the standards applicable to rebuttal experts are different from those governing affirmative expert testimony. A rebuttal expert’s function is to identify flaws in the opposing expert’s analysis, not necessarily to construct a competing model. Although courts have recognized that rebuttal experts may, in appropriate circumstances, offer independent opinions or utilize alternative methodologies, nothing in Rule 26 requires them to do so.

    Case Details:

    Case Caption: Stonewater Roofting Ltd. Co., LLC V. Merryton Bossier, LLC
    Docket Number: 5:22cv1048
    Court Name: United States District Court, Louisiana Western
    Order Date: December 17, 2025
  • Maritime Safety Expert Was Barred From Opining on Structural Integrity

    Maritime Safety Expert Was Barred From Opining on Structural Integrity

    At its core, this case involves an alleged injury on a ship. Specifically, Plaintiffs Robert Mondella and Tara Mondella allege that Mr. Mondella was seriously injured when he fell from a gangway while performing services on board the JPO Capricornus (the “Capricornus”), a vessel owned by Defendants.

    Defendants filed a motion to exclude the report and testimony of Plaintiffs’ expert Captain Joseph Ahlstrom.

    Defendants challenge each of the enumerated opinions in Capt. Ahlstrom’s report on at least one of the following grounds: (1) that he is unqualified; that his opinions are speculative, conjectural, or otherwise rely on insufficient evidence; and (3) that he relied on principles or methods that are inappropriate or otherwise improper for expert testimony.

    Maritime Safety Expert Witness

    Captain Joseph F. Ahlstrom is a graduate of the State University of New York (SUNY) Maritime, with a bachelors degree in marine transportation. He completed his masters degree in transportation management with honors from SUNY Maritime College. Captain Ahlstrom has commanded six merchant ships, including a tanker, containership, breakbulk carrier, and research and training ship. He sailed for fifteen years in the U.S. and Foreign Merchant Marine. In January 1996, Captain Ahlstrom started teaching at SUNY Maritime College. During his time at SUNY Maritime he was captain of the Training Ship Empire State from 1998–2000. He also was chairman of the Marine Transportation Department from 2003 until May 2005.

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

    Discussion by the Court

    Defendants challenged each of the enumerated opinions in Capt. Ahlstrom’s report on at least one of the following grounds: (1) that he is unqualified; (2) that his opinions are speculative, conjectural, or otherwise rely on insufficient evidence; and (3) that he relied on principles or methods that are inappropriate or otherwise improper for expert testimony.

    Qualifications

    Defendants argued that Capt. Ahlstrom “is not a metallurgist, possesses no educational background, training, or experience in the field of metallurgy, and is not qualified to opine on metallurgical matters (i.e., whether the pin was rusted or corroded, leading it to be in a ‘defective’ condition).”

    Although Capt. Ahlstrom is an expert, his expertise on “hundreds if not thousands of [gangways]” demonstrates that he has experience generally with the type of gangway pin at issue, but it does not demonstrate that his expertise extends to qualify him to render the testimony about the condition and structural integrity of the pin at issue here.

    Capt. Ahlstrom does not need to be a classically trained metallurgist, but he must have experience such that the Court is persuaded that his opinions on the condition of the at-issue pin are as reliable as his opinions based on other pins that were available for him to inspect in person. Plaintiffs have failed to demonstrate that Capt. Ahlstrom has experience in evaluating the condition of gangway pins through a single photograph.

    Because Plaintiffs have not demonstrated that Capt. Ahlstrom has such experience, Plaintiffs have failed to demonstrate by a preponderance of the evidence that Capt. Ahlstrom is qualified to testify about matters of deterioration or structural integrity under these circumstances.

    Methodology

    i. Capt. Ahlstrom’s Testimony is not Based on Sufficient Data

    At bottom, Defendants relied on the fact that Capt. Ahlstrom did not inspect the relevant pin or gangway in person. Although the failure to conduct such inspection is not enough, by itself, to render expert testimony unreliable, Plaintiffs did not demonstrate that his testimony concerning his review of the available materials is reliable.

    Plaintiffs conceded that without the tangible pin, their expert would not have access to sufficient facts or data necessary to determine the pin’s condition—those concessions are fatal.

    If there was not enough information for Plaintiffs’ expert to determine material facts about the pin’s condition then, there is certainly not enough information now. Plaintiffs cannot credibly demonstrate that Capt. Ahlstrom’s testimony regarding the subject pin is based on sufficient facts or data. In other words, “there is simply too great an analytical gap between the data and the opinion proffered.”

    That analytical gap renders the portions of the testimony that concern the condition of the pin speculative and conjectural. Because Rule 702 bars such speculative and conjectural testimony, the Court must preclude it.

    ii. Capt. Ahlstrom’s Testimony is not the Product of Reliable Principles and Methods

    One of Capt. Ahlstrom’s opinions is nothing more than an expert “simply accumulating and putting together one party’s story,” which is “expressly prohibited.” 

    Moreover, Capt. Ahlstrom’s failure to consider potential alternative explanations, and Plaintiffs’ failure to address this deficiency, further undermine the Court’s confidence that the subject testimony is the product of reliable principles and methods.

    According to the Court, Capt. Ahlstrom provided legal conclusions about the duty of care and causation, disguised as his opinion.

    Plaintiffs’ failure to demonstrate that their proposed expert’s testimony “is the product of reliable principles and methods,” or “a reliable application of the principles and methods to the facts of the case” is particularly troubling, as the principles-and-methods components of Rule 702 is the crux of the Court’s inquiry.

    Held

    The Court granted Defendants’ motion to exclude the report and testimony of Capt. Joseph Ahlstrom .

    Key Takeaway

    Concerns about the reliability of Capt. Ahlstrom’s reasoning and methodology, the sufficiency of available data, and the other infirmities discussed above lead the Court to the inescapable conclusion that Capt. Ahlstrom’s testimony will not assist the trier of fact. Taken together, Plaintiffs failed to demonstrate that Capt. Ahlstrom’s testimony satisfies even one of the four requirements of Rule 702. Therefore, the Court found “that there is simply too great an analytical gap between the data and the opinion proffered.” That analytical gap renders Capt. Ahlstrom’s testimony at best, irrelevant, useless, and sure to waste time.

    Case Details:

    Case Caption: Mondella V. Schiffahrtsgesellschaft Oltmann MBH & Co. KG
    Docket Number: 1:20cv1059
    Court Name: United States District Court, New York Eastern
    Order Date: December 15, 2025
  • Compliance Expert Was Allowed to Opine on Amazon Policy

    Compliance Expert Was Allowed to Opine on Amazon Policy

    ZAGG initiated this action against DVG, TX Trading Inc. (“TX Trading”), and Menachem Mendel Ichilevici (“Ichilevici”) (collectively, “Defendants”), alter egos collectively doing business as Amazon Seller “Mac N’ Cheese,” violated Sections 32 and 43 of the Lanham Act, 15 U.S.C. §§ 1114, 1125(a), by infringing on ZAGG’s trademarks and falsely advertising ZAGG products.

    Plaintiff, ZAGG, Inc., filed a Daubert motion to exclude the report and testimony of DVG’s Amazon policy expert, Rachel Johnson Greer.

    Compliance Expert Witness

    Rachel Johnson Greer worked as a Program Manager at Amazon for five years, overseeing various elements of Amazon’s compliance programs. She has has served as an Amazon compliance consultant since 2015. Greer published a book on Amazon product safety. She has appeared as an “Amazon Product Compliance” speaker at various events from 2016 to 2022.

    Greer received a Master of Business Administration degree from Seattle University.

    Discover more cases with Rachel Johnson Greer as an expert witness by ordering his comprehensive Expert Witness Profile report.

    Discussion by the Court

    I. Qualifications

    ZAGG claimed that Greer is “an unqualified and unreliable witness as to Amazon’s current processes and policies (or any policies after she left in 2017).”

    However, Greer’s experience both as a manager at Amazon and as a consultant to Amazon sellers qualifies her as an expert in the field of “Amazon policy compliance.”

    Despite Greer’s demonstrated experience in the Amazon marketplace, ZAGG attacked her qualifications in four ways. First, ZAGG claimed that none of Greer’s roles at Amazon “involved any of the issues or policies at issue in this case.” But that’s not entirely true. Greer “investigated sellers and vendors for safety and intellectual property infringement,” “managed quality & compliance for Amazon’s own brands,” and “managed the legal compliance of all global imports.”

    Second, ZAGG contended that Greer isn’t qualified because she hasn’t worked at Amazon since 2017 and thus (ZAGG says) isn’t familiar with Amazon’s “current processes and policies.” But ZAGG hasn’t cited any authority for the proposition that an expert must be currently (or even recently) employed by a company whose policies he or she intends to outline.

    Third, ZAGG insisted that “only Amazon itself can testify as to its practices and procedures.” However, courts routinely allow experts who are unaffiliated with a company to testify about that company’s policies or practices if those experts are otherwise qualified to do so. To the extent ZAGG thinks that Amazon would be a better witness, it hasn’t identified any authority that requires the Court to exclude an expert’s testimony simply because a better witness might have been found.

    Finally, ZAGG claimed that Greer is impermissibly trying to “testify on behalf of Amazon.” The Greer Report made it clear that Greer is offering her perspective on Amazon’s policies and practices as an expert who’s navigated the Amazon marketplace for years.

    II. Reliability

    Because Greer is a non-scientific expert testifying about her experience, the relevant question is “how that experience leads to the conclusion reached, why that experience is a sufficient basis for the opinion, and how that experience is reliably applied to the facts.”

    Greer has shown that her opinions about Amazon’s policies and practices are based, in part, on her experience “providing compliance guidance to Amazon sellers regarding Product Policy, Fulfilment by Amazon (‘FBA’) compliance, Amazon’s intellectual property policies, and other Seller Performance issues,” and “providing advisory services on meeting Amazon and regulatory product compliance requirements for consumer goods.”

    Her “opinions in this case are based on her experience working at Amazon and in her Amazon consulting business, Amazon policy documents, publicly available listings of ZAGG products on Amazon.com, and her review of certain documents provided to her by DVG.” That’s more than sufficient for the Court to find her report and testimony reliable under Rule 702.

    Since Greer’s proposed testimony is based on her personal experience working with Amazon’s quality control policies over many years, the Court denied the second aspect of ZAGG’s motion.

    III. Helpfulness

    ZAGG argued that the Greer Report is not helpful because it “contains exclusively fact testimony and is completely devoid of any opinions that go beyond the understanding of an average layperson.”

    However, DVG argued that Greer does much more than just recite Amazon policies and procedures. In saying so, DVG identifies several of Greer’s opinions that (it believes) will help the trier of fact, including:

    • Amazon public-facing policies “are often contradictory or outdated” because “Amazon’s process for changing and updating policies, guidelines and other seller documents on the Amazon Marketplace is a multi-step process that requires internal tickets and up to six approvals.”
    • “Based on her experience at Amazon and in providing consulting services to Amazon sellers, it has always been understood that a “new” item is simply one that is brand-new and unused, free of blemishes, smudges or dirt, and in the original packaging.”

    The Court agreed with DVG that Greer’s report and testimony go well beyond a mere recitation of Amazon’s policies and that her expert analysis of Amazon’s policies and practices would assist the trier of fact. The Court thus denied this third aspect of ZAGG’s motion.

    IV. Opinions & Hearsay

    First, ZAGG said that “it is entirely unclear what ‘opinions’ are being offered by Greer.” ZAGG claimed that the Greer Report is “a hodgepodge of speculative factual assertions made by Greer masquerading as ‘opinions.’”

    However, in making this argument, ZAGG identified several of Greer’s specific opinions—thus belying its claim that it has no way of knowing which opinions Greer plans to offer. (“Greer testified that she is offering only two opinions. First, she testified that: ‘Accordingly, it is my opinion that ZAGG’s conclusion that defendants cannot list ZAGG products as being in new condition is based on an incorrect interpretation of Amazon’s policies that is not used by Amazon in practice.’ Second, she testified that: ‘it is my opinion that defendants’ stickering of ZAGG products comports with Amazon’s policy, as does the marking over the barcode on the lower left of the packaging above.’”)

    Second, ZAGG believed that Greer’s opinions are merely “out-of-court assertions about Amazon’s policies and practices, offered for their truth.”

    The Court held that Greer’s testimony isn’t a mere recounting of the out-of-court statements of others—it’s expert analysis about the industry’s business practices gleaned from her years of experience as an Amazon employee and consultant.

    Held

    The Court denied ZAGG’s motion to exclude the report of DVG’s expert, Rachel Johnson Greer.

    Key Takeaway

    Knowledge of an industry’s business practices is gleaned from years of working within the industry and with its professionals. It is not a recounting of out of court statements of others.

    Case Details:

    Case Caption: Zagg Inc. V. TX Trading, Inc.
    Docket Number: 1:23cv20304
    Court Name: United States District Court, Florida Southern
    Order Date: December 16, 2025
  • Piloting Expert Was Allowed to Opine on Spatial Disorientation

    Piloting Expert Was Allowed to Opine on Spatial Disorientation

    This case arises from an accident involving a Robinson R44 II helicopter, registration N442VB (“Helicopter”), that occurred on the evening of December 30, 2021, in Levy County, Florida. The Helicopter was being flown at night by the owner-pilot, Ronald Hicks (“Pilot Hicks”), from a local friend’s residence to his private property. At the time of the accident, Pilot Hicks had less than ten hours of night flight experience in helicopters and was not certified under Instrument Flight Rules (“IFR”). Mr. Hicks, Shelly Kate Hicks, and their two children sustained fatal injuries.

    Plaintiffs filed a Daubert motion to exclude and/or limit the testimony of Defendant’s piloting expert Timothy Tucker.

    Piloting Expert Witness

    Timothy C. Tucker has 55 years’ experience as a military and civilian helicopter pilot, instructor and evaluator in both visual and instrument flight
    techniques.

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

    Discussion by the Court

    Qualification

    Plaintiffs argud that Tucker opined regarding “meteorology, engine failure, accident reconstruction, and human factors issues” despite being unqualified to do so.

    The Court has reviewed Tucker’s expert report and found that he is qualified as a “piloting” expert and may opine from the piloting perspective. However, Tucker was not qualified as a metallurgist or accident reconstructionist, and his report did not indicate that he relied upon Defendant’s metallurgy or accident reconstruction experts when forming his conclusions.

    While Tucker may offer his “piloting” opinions, he may neither (1) repeat the conclusions of Defendant’s metallurgy and accident reconstruction experts, nor (2) say they are consistent with his opinions. Moreover, Tucker is strictly limited to offering only the “piloting” opinions outlined in his report. Defendant represented that Tucker will testify to two main opinions, that Hicks “experienced spatial disorientation and lost control” of the helicopter, and that the evidence in this case is inconsistent with an attempted autorotation.

    Methodology

    Second, Plaintiffs argued that Tucker’s methodology was unreliable. Plaintiffs took issue with Tucker’s reliance on flight path ADS-B data for his analysis and the fact that his opinion purportedly conflicts with other witness testimony regarding the crash.

    While Plaintiffs are free to cross-examine Tucker regarding perceived deficiencies in his data or conclusions, they have not demonstrated exclusion is warranted.

    Third, Plaintiffs argued that Tucker’s opinion will be cumulative. As explained above, the Court found that Tucker is a qualified “piloting” expert and may opine from that unique perspective. To the extent Tucker is offering the “piloting” opinions in his report, his testimony is not cumulative. However, the Court reiterates that it will not tolerate Tucker offering other experts’ testimony or saying it comports with his own. This will be strictly enforced.

    Finally, Plaintiffs requested that Tucker be bound to the opinions contained within his expert report. The Court absolutely agreed that no expert may offer opinions not within their expert report.

    Held

    The Court denied the Plaintiffs’ Daubert motion to exclude and/or limit the testimony of Defendant’s expert Timothy Tucker.

    Key Takeaway

    Whether an expert selected the best data set to use is a question for the jury, not the judge. Vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.

    Please refer to the blogs previously published about this case:

    Accident Reconstruction Expert’s Meteorological Opinions Excluded

    Avionics Expert Allowed to Opine on Engine Failure

    Case Details:

    Case Caption: Law V. Avco Corporation
    Docket Number: 1:24cv3
    Court Name: United States District Court for the Northern District of Florida, Gainesville Division
    Order Date: November 05, 2025
  • Nutrition Expert Was Allowed to Opine on the Use of Statutes and Regulations

    Nutrition Expert Was Allowed to Opine on the Use of Statutes and Regulations

    Plaintiffs are the estates of three decedents, Robert W. Petersen (“Mr. Petersen”), Mary Ann Simons, (“Ms. Simons”) and Charlotte Elaine Guilford (“Ms. Guilford”) (collectively, “Plaintiffs”). Plaintiffs were residents of Canyon Creek, an assisted living facility in Billings, Montana specializing in memory care, during the height of the COVID-19 pandemic in 2020. Plaintiffs alleged that Canyon Creek was negligent in the care of Mr. Petersen, Ms. Simons, and Ms. Guilford and that its negligent care caused their deaths.

    One of Plaintiffs’ allegations in this case is that Canyon Creek failed to ensure that Petersen and Simons maintained acceptable parameters of nutrition and hydration as required by state statute and federal regulation.

    Plaintiffs retained Janet McKee, a registered dietician, as their expert on the standard of care regarding how assisted living facilities monitor residents’ nutritional status and needs.

    However, Defendants filed a motion to exclude McKee’s testimony under Federal Rule of Evidence 702, arguing that her opinions exceed the scope of her qualifications, are based on insufficient facts and data, and are not supported by a reliable assessment of the applicable standard of care. Defendants next filed a motion in the alternative to limit McKee’s testimony. They first argued that she lacked the qualifications to offer medical causation opinions or to use statutes or regulations to establish a duty and should therefore be prohibited from proffering such opinions. Second, they argued that any testimony about, reliance upon, or reference to opinions and information first disclosed during McKee’s deposition should be excluded from trial pursuant to Federal Rules of Civil Procedure 26 and 37.

    Nutrition Expert Witness

    Janet Sutton McKee holds a Master of Science in Food, Nutrition, and Institutional Management and a Bachelor of Science in Home Economics Education. She is a registered dietician and nutritionist and holds licenses in nine states.

    Also, she is board certified as a specialist in gerontological nutrition and currently, she is the owner and manager of a nutrition and foodservice consulting company that services healthcare facilities, including acute care, skilled nursing and long-term care, residential psychiatric and behavioral treatment, and assisted living centers throughout the United States.

    Discover more cases with Janet McKee as an expert witness by ordering her comprehensive Expert Witness Profile report.

    Discussion by the Court

    A. Motion to Exclude Testimony of Plaintiffs’ Expert Janet McKee

    1. Qualifications

    McKee has delivered extensive educational programs and presentations nationwide for healthcare associations, industry conventions, and professional groups, covering topics including nutrition’s role in fall prevention, geriatric care, quality assurance, pandemic response, and liability reduction.

    Also, she has developed and taught nutrition courses at the university level and for healthcare professionals. Further, she has conducted and published clinical research and authored/co-authored numerous articles and chapters on clinical nutrition topics, liability risk management, and speciality dietetics.

    In other words, the Court held that McKee’s knowledge, skill, experience, and education are relevant to the opinions she offers regarding Canyon Creek’s dietary standard of care duties.

    2. Reliability

    The Court determined that McKee’s opinions satisfy the preponderance standard for admissibility, albeit marginally. First, McKee’s opinions are based on sufficient facts and data.

    Although McKee did not cite specific documents and conceded that she would have preferred to review additional material, the Court nonetheless acknowledges that her testimony appears grounded in record evidence, as shown by the “thousands of pages” she produced at her deposition.

    Moreover, McKee’s opinions reflected a reliable application of her experience, training, and education to the facts of the case. 

    For example, McKee opined that Canyon Creek failed to weigh Mr. Petersen on admission and that its negligence caused his weight loss, malnutrition, falls, dehydration, and pressure wounds, as well as a decreased quality and length of life. At deposition, however, she acknowledged not knowing when Petersen was admitted, not possessing his pre-admission records, and not being aware of his prior quality of life or whether he had preexisting pressure injuries. Absent this information, Defendants argued that her opinions are unreliable.

    However, McKee did offer opinions relevant to her experience and supported by the record regarding Petersen’s condition and treatment at Canyon Creek.

    Because McKee’s opinions rest on sufficient facts and data and reliably apply her expertise to the facts of this case, the Court denied Defendants’ motion to exclude.

    B. Alternative Motion to Limit Testimony

    1. Causation Opinions and Establishing a Duty

    In the alternative, Defendants next moved to limit, in limine, McKee’s testimony by prohibiting her from offering causation opinions or using statutes or regulations to establish a duty.

    a. Causation Opinions

    Defendants first argued that McKee should be prohibited from opining that Canyon Creek caused Plaintiffs’ medical diagnoses or that Canyon Creek “promoted” Plaintiffs’ medical outcomes.

    Plaintiffs did not intend to elicit a causation opinion from McKee. Therefore, the Court granted the alternative motion to limit testimony as to eliciting causation opinions.

    However, the Court agreed with Plaintiffs that McKee “is uniquely positioned to render an opinion on the risks attendant to poor nutrition.”

    b. Establishing a Duty

    Defendants next argued that McKee cannot use statutes or regulations to evidence a standard of dietary care because she only opined that Canyon Creek violated the cited statutes and regulations, not that the statutes and regulations embodied an applicable standard of care.

    Because McKee failed to identify laws embodying the standard of care, Defendants argued that she is not qualified to determine which statutes and regulations establish a duty applicable to Canyon Creek.

    Based on McKee’s testimony and qualifications discussed above, the Court allowed her to opine on how the regulations and statutes she identified inform the standard of care and create a duty in this case. Plaintiffs did not intend to elicit ultimate issue opinions from McKee.

    The Court denied the alternative motion to limit testimony as to McKee’s use of statutes and regulations to identify a standard of care and establish a duty.

    2. Federal Rules of Civil Procedure 26 and 37

    a. Rule 26

    The Court found that McKee introduced new opinions in her Violations Report and throughout her deposition that were neither adequately disclosed nor supplemented by Plaintiffs.

    After reviewing McKee’s Initial Report alongside her Violations Report, the Court found that though the documents are fundamentally aligned, they differ in breadth and scope, in their regulatory and legal framing, and in their identification of infection control and systemic failures.

    Disclosures by experts are not living documents that can be added to on a continuing basis. If the Court were to treat McKee’s disclosures in this fashion, then “the full disclosure requirement implicit in Rule 26 … would interfere with the Court’s ability to set case management deadlines, because new reports and opinions would warrant further consultation with one’s own expert and virtually require new rounds of depositions.”

    In addition to improper disclosure, Plaintiffs failed to adequately supplement McKee’s Initial Report under Rule 26(e). It is obvious that the additional material McKee relied on and the new opinions she formed after her disclosure far exceed the scope of Rule 26(e), that is—”correcting inaccuracies or filling the interstices of an incomplete report.”

    Accordingly, Plaintiffs violated Rule 26 when they failed to adequately disclose or supplement McKee’s Initial Report with the numerous new opinions from her Violations Report and the detailed analysis she provided at her deposition.

    b. Rule 37

    The Court found that the late disclosure was neither substantially justified nor harmless. Initially, the late disclosure deprived Defendants of a meaningful opportunity to prepare for, examine, and respond to McKee’s new opinions at her deposition. True, Plaintiffs complied with Defendants’ subpoena. However, had Defendants not subpoenaed McKee, they may not have learned about the new materials she relied on or her new opinions until trial. Plaintiffs offer no reason why the additional materials or new opinions were not properly supplemented under Rule 26(e) before McKee’s deposition, and therefore, the late disclosure was not justified.

    The Court next rejected Plaintiffs’ contention that the late disclosure was harmless because Defendants violated the parties’ agreement not to produce expert notes.

    McKee’s “notes” advanced her opinions far beyond the scope of her summary analysis in her Initial Report. And even though Defendants have known the totality of McKee’s opinions for over a year, it was Plaintiffs’ duty to adequately disclose and supplement under Rule 26.

    Here, the Court ultimately concluded that the risk of any prejudice to Defendants at trial is mitigated by two factors. First, despite Plaintiffs’ procedural infraction, Defendants have had adequate time to prepare for trial since they learned of McKee’s late disclosure 15 months ago. Second, expert testimony is an essential component to litigating the parties’ case; as such, there are less drastic sanctions available than striking portions of McKee’s opinions that would promote a fair trial. The jury should be allowed to weigh the entirety of Plaintiffs’ experts’ opinions.

    Therefore, the Court elects to impose the lesser sanction of allowing Plaintiffs to file McKee’s supplemental expert report and allowing Defendants to reopen McKee’s deposition.

    Held

    (1) The Court denied the Defendants’ motion to exclude the testimony of Plaintiffs’ expert Janet McKee.

    (2) The Court granted in part and denied in part the Defendants’ alternative motion to limit testimony.

    Key Takeaway

    Although certain aspects of McKee’s testimony may lack foundation in pre-admission records or prior medical history, her analysis of Canyon Creek’s care practices are nonetheless grounded in her professional experience and supported by the record. Therefore, her opinions are reliable.

    Please refer to the blogs previously published about this case:

    Palliative Care Expert’s New and Expanded Opinions on Facility Neglect Admitted

    Economics Expert Was Allowed to Opine on Assisted Living Facility Administration Issues

    Case Details:

    Case Caption: Estate Of Robert W. Petersen Et Al V. Koelsch Senior Communities LLC
    Docket Number: 1:22cv11
    Court Name: United States District Court, Montana
    Order Date: December 12, 2025
  • Accident Reconstruction Expert’s Meteorological Opinions Excluded

    Accident Reconstruction Expert’s Meteorological Opinions Excluded

    This case arises from an accident involving a Robinson R44 II helicopter, registration N442VB (“Helicopter”), that occurred on the evening of December 30, 2021, in Levy County, Florida. The Helicopter was being flown at night by the owner-pilot, Ronald Hicks (“Pilot Hicks”), from a local friend’s residence to his private property. At the time of the accident, Pilot Hicks had less than ten hours of night flight experience in helicopters and was not certified under Instrument Flight Rules (“IFR”). Mr. Hicks, Shelly Kate Hicks, and their two children sustained fatal injuries.

    Plaintiffs filed a Daubert motion to exclude and/or limit the testimony of Defendant’s accident reconstruction expert Douglas Stimpson.

    Accident Reconstruction Expert Witness

    Douglas Earl Stimpson has been continually employed in the aviation industry for over 54 years and has participated in over 3,500 aviation accident reconstructions.

    He has been a Commercial Pilot and Flight Instructor for over five decades and currently holds FAA certifications as a Commercial Pilot Rotorcraft Helicopter, Certified Flight Instructor Helicopter, Certified Flight Instructor Instruments, and Advanced Ground Instructor.

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

    Discussion by the Court

    First, Plaintiffs argued that Stimpson opined regarding “meteorology, metallurgy, and human factors issues” despite being unqualified to do so.

    This Court has reviewed Stimpson’s expert report and found that he is qualified as an accident reconstruction expert and may opine from that perspective. He may also rely upon the opinions of Defendant’s other experts when forming his own accident reconstruction opinions, provided he explains he is doing so. However, Stimpson is not qualified as a piloting or meteorological expert. Therefore, he may not offer new piloting or meteorological opinions or offer Defendant’s other experts’ opinions as his own. If Stimpson’s testimony begins to venture beyond these boundaries, this Court is prepared to rein it in immediately.

    Second, the Plaintiffs argued that Stimpson’s methodology was unreliable. Plaintiffs take issue with Stimpson’s reliance on flight path ADS-B data for his analysis and the fact that his opinion purportedly conflicts with at least one eyewitness’ testimony regarding the crash. Therefore, while Plaintiffs are free to cross-examine Stimpson regarding perceived deficiencies in his data or conclusions, they have not demonstrated exclusion is warranted.

    Third, Plaintiffs argued that Stimpson’s opinions are cumulative because they overlap with Defendant’s other experts. As explained above, the Court found that Stimpson is a qualified accident reconstruction expert and may opine from that unique perspective. To the extent Stimpson is offering the accident reconstruction opinions in his report, his opinions are not cumulative.

    Finally, Plaintiffs requested that Stimpson be bound to the opinions contained within his expert report. This Court absolutely agreed that no expert may offer opinions not within their expert report.

    Held

    The Court granted in part Plaintiffs’ Daubert motion to exclude and/or limit the testimony of Douglas Stimpson.

    Key Takeaway

    Whether an expert selected the best data set to use is a question for the jury, not the judge. Vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.

    Case Details:

    Case Caption: Law V. Avco Corporation
    Docket Number: 1:24cv3
    Court Name: United States District Court for the Northern District of Florida, Gainesville Division
    Order Date: November 6, 2025
  • Accounting Expert was Allowed to Opine on the Fair Market Value

    Accounting Expert was Allowed to Opine on the Fair Market Value

    Upper Deck claimed that Pixels has marketed and sold wall décor featuring images that infringe upon Upper Deck’s trademarks and Michael Jordan’s name, image, likeness, and publicity rights. Basically, Upper Deck brought this action pursuant to an exclusive agreement with Jordan (the “Jordan Agreement”) for the use of his name, image, likeness, and other publicity rights. Upper Deck asserted that the agreement also gives Upper Deck the right to commence actions on behalf of Jordan for infringement of the rights assigned in the Jordan Agreement.

    Amongst other things, Upper Deck alleged violation and deprivation of the right of publicity, violations of the Lanham Act, registered trademark infringement, violation of California’s Unfair Competition Law, and California common law unfair competition. 

    Christian Tregillis was retained as a damages expert by Upper Deck to opine on the fair market value of Pixels’ alleged unauthorized use of Jordan’s rights. Pixels filed a motion to exclude Tregillis’ testimony, contending that his methodology is unreliable and based upon insufficient facts and data.

    Pixels also contended that the premium multiplier Tregillis uses in his fair market value calculation is unreliable and that Tregillis’s two “Evidence Indicates” opinions are irrelevant.

    Accounting Expert Witness

    Christian Dale Tregillis holds an M.B.A. in Finance and Accounting. He has more than thirty years of experience analyzing financial, accounting, economic, statistical, and market issues, primarily relating to disputes, valuations, and license agreements covering intellectual property rights.

    Tregillis has held leadership positions with many public accounting and licensing professional groups. He is also accredited in Business Valuation and certified in Financial Forensics, Public Accounting, and Licensing.

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

    Discussion by the Court

    A. Methodology

    Tregillis calculated the fair market value of Pixels’ use of Jordan’s rights by analyzing comparable licenses for rights similar to those used by Pixels as a starting point to construct a hypothetical license.

    Tregillis then adjusted the value of the benchmark comparable license to account for the other athletes included in the benchmark license, the length of time of Pixels’ use, and the fact that Pixels’ use of Jordan’s rights was not subject to any quality assurance or approval clauses. Pixels argued that the benchmark agreement chosen by Tregillis is insufficiently comparable and that Tregillis made improper assumptions to inflate the value of the benchmark license.

    1. Underlying Facts and Data

    Tregillis determined the Trends Agreement to be the most comparable to the facts at issue here and uses this agreement as the benchmark for his hypothetical license analysis. The Trends Agreement was a licensing agreement between Brevettar, described as “the exclusive licensing agent for Upper Deck,” and Trends International, LLC. The Trends Agreement granted Trends a license to manufacture, distribute, and sell collector’s edition posters and calendars featuring the name, image, likeness, signature, and statistical data of Michael Jordan, Wayne Gretzky, and Tiger Woods. A later amendment to the Trends Agreement also allowed Trends to sell canvas wall décor.

    Pixels argued that the Trends Agreement is an improper comparable because Upper Deck was not a party to it, Upper Deck did not receive royalty payments from the agreement, and the Trends Agreement was not effective until two and a half years after Pixels alleged unauthorized sales began.

    Here, the Trends Agreement concerned the same rights at issue in this case, Jordan’s name, image, likeness, and publicity rights. Further, the Trends Agreement covered the same types of products as those at issue here—posters, calendars, and wall décor. The Trends Agreement also covered products similarly priced to those sold by Pixels. Consequently, the Court found the Trends Agreement sufficiently comparable to serve as a reliable basis for the hypothetical license analysis Tregillis conducts.

    2. The Premium Multiplier

    After identifying the Trends Agreement as the best benchmark for his hypothetical license analysis, Tregillis used a premium multiplier to adjust for the fact that Pixels’ use of Jordan’s rights was not authorized and not subject to the quality assurance and approval clauses typically included in Jordan’s licensing agreements.

    Tregillis calculated this multiplier by comparing two similar situations where Jordan’s rights were used, one of which was authorized (the “Hanes Transaction”) and one of which was unauthorized (the “Panini Settlement”). ) Tregillis compared the values of those transactions to calculate the percentage premium for unauthorized uses of Jordan’s rights.

    Pixels argued that the application of this premium multiplier is unreliable and that the Hanes Transaction and Panini Settlement are not reliably comparable to the conduct at issue here.

    Tregillis demonstrated the necessity of this premium adjustment by discussing Jordan’s carefully tailored brand and restrictive approach to licensing agreements.

    Then, Tregillis conducted a comparative analysis using otherwise analogous transactions to calculate the value of unauthorized uses of Jordan’s rights. This analysis is grounded in evidence, and Tregillis’s application of his analysis logically follows. Therefore, the premium multiplier calculation and its application to the hypothetical license are sufficiently reliable to present to a jury. 

    Tregillis spent paragraphs of his report, supported by citations to the record, discussing the Hanes Transaction and Panini Settlement as well as how he used them in his analysis.

    Tregillis did not use the Hanes Transaction and Panini Settlement as comparable to this case for the purpose of hypothetical license analysis; rather, he uses them in a comparative analysis to determine the value of Jordan’s rights when their use is not subject to any quality assurance or approval clauses.

    B. The “Evidence Indicates” Opinions

    Tregillis offered two “Evidence Indicates” opinions. First, “Evidence indicates that, as Upper Deck values its relationship with Jordan, one of the world’s most iconic athletes and personalities, Upper Deck protects both its rights and Jordan’s rights, while also ensuring it only produces and/or approves high-quality products that feature appropriate and value-enhancing uses of Jordan’s rights of publicity and trademarks.” And second, “Evidence indicates that the use made by Pixels is unauthorized and would not have been authorized by Jordan and/or Upper Deck.” Pixels argued that these opinions are irrelevant and should be excluded.

    The Court found that the two “Evidence Indicates” opinions will aid the jury in understanding Tregillis’ hypothetical license analysis. The “Evidence Indicates” opinions shed light on the fair market value of Jordan’s rights as Pixels used them and demonstrate the necessity of the premium multiplier. More specifically, the opinions will help the jury to understand how Upper Deck and Jordan value Jordan’s rights and typically license them.

    Pixels argued that the second “Evidence Indicates” opinion “is a naked attempt to elevate Upper Deck’s allegations of unauthorized use by Pixels into a liability opinion against Pixels.”

    The Court agreed that Tregillis’ second “Evidence Indicates” opinion goes to brand standards and addresses how the fair market value of Jordan’s rights is impacted when subject to quality assurance and approval clauses.

    However, grounding the second “Evidence Indicates” opinion in language about “authorization” toes the line of embodying a legal conclusion. Accordingly, while the Court found that Tregillis is not offering a legal conclusion, his testimony at trial should make clear that Tregillis is merely assuming Pixels’ liability for the purposes of his analysis and is offering opinions about authorization solely to support his damages analysis, not to offer a legal conclusion. 

      Held

      The Court denied Defendant Pixels.com’s motion to exclude the testimony of Plaintiff The Upper Deck Company’s expert witness, Christian Tregillis.

      Key Takeaway:

      Any lingering doubts as to the negative impact of Tregillis’s testimony can be managed by instructing the jury to follow only the judge’s instructions as to what the law is and to disregard any testimony that is inconsistent with those instructions.

      Case Details:

      Case Caption: The Upper Deck Company V. Pixels.Com, LLC
      Docket Number: 3:24cv923
      Court Name: United States District Court, California Southern
      Order Date: December 09, 2025
    1. Public Health Expert Was Allowed to Opine on the Quality of Care

      Public Health Expert Was Allowed to Opine on the Quality of Care

      This is a securities class action, led by Chicago Laborers’ Pension Fund and New York Hotel Trades Council & Hotel Association of New York City, Inc. Pension Fund (collectively, “Plaintiffs”).

      Plaintiffs alleged that Acadia Healthcare Company, Inc. (“Acadia”) and several of its current and former executives, including David M. Duckworth, Brent Turner, and Joey A. Jacobs (collectively, “Defendants”) made false and misleading statements to investors regarding Acadia’s business.

      Defendants filed a motion to exclude the testimony and opinions of Plaintiff’s expert witness Dr. Ashish K. Jha.

      Public Health Expert Witness

      Ashish Kumar Jha is an American general internist physician and academic who served as the White House COVID-19 response coordinator from 2022–2023. He has been Dean of the Brown University School of Public Health since 2020.

      Prior to Brown, he was the K.T. Li Professor of Global Health at Harvard T.H. Chan School of Public Health, faculty director of the Harvard Global Health Institute, and a Senior Advisor at Albright Stonebridge Group.

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

      Discussion by the Court

      Defendants did not dispute that Jha is qualified as an expert to opine on the quality of care offered at Acadia’s mental healthcare facilities during the Class Period. Instead, they contended that his opinions on that issue should be excluded as irrelevant because he did not opine about the quality of care offered at Acadia’s facilities “on the whole,” and that his opinions about assessing the quality of care offered at Acadia’s mental health facilities should be excluded as unreliable for failing to provide factual context that Defendants think is important.

      Plaintiffs responded by first noting that Jha’s overarching opinions concerned the quality of care offered in all of Acadia’s facilities and that such evidence is highly probative of falsity as to the challenged quality care misstatements. Next, Plaintiffs argued that Jha’s opinions are reliable. Plaintiffs submitted that Defendants’ motion ignored Jha’s detailed explanation, supported by considerable scholarship, of why it was appropriate to compare Acadia’s standalone, for-profit inpatient facilities to other standalone, for-profit inpatient facilities to prevent confounding variables from prejudicing the analysis.

      The Court found that Plaintiffs have shown by a preponderance of the evidence that Jha is qualified, his opinions have a reliable basis in the knowledge and experience of his discipline, and that he will testify to knowledge that will assist the trier of fact in understanding the evidence about the quality of care offered at Acadia’s mental healthcare facilities during the Class Period and deciding whether Defendants’ challenged statements regarding the same were knowingly false when made.

      Held

      The Court denied the Defendants’ motion to exclude the testimony and opinions of Plaintiff’s expert witness Dr. Ashish K. Jha.

      Key Takeaway:

      Although the Defendants also attacked Jha’s methodology, those arguments did not show that Jha’s opinions are “so fundamentally unsupported that it can offer no assistance to the [trier of fact]” under the facts of this case.

      Please refer to the blog previously published about this case:

      Economics Expert Allowed to Opine on Stock Inflation

      Case Details:

      Case Caption: St. Clair County Employees’ Retirement System V. Acadia Healthcare Company, Inc. Et Al
      Docket Number: 3:18cv988
      Court Name: United States District Court for the Middle District of Tennessee, Nashville Division
      Order Date: November 07, 2025
    2. Avionics Expert Allowed to Opine on Engine Failure

      Avionics Expert Allowed to Opine on Engine Failure

      This case arises from an accident involving a Robinson R44 II helicopter, registration N442VB (“Helicopter”), that occurred on the evening of December 30, 2021, in Levy County, Florida. The Helicopter was being flown at night by the owner-pilot, Ronald Hicks (“Pilot Hicks”), from a local friend’s residence to his private property. At the time of the accident, Pilot Hicks had less than ten hours of night flight experience in helicopters and was not certified under Instrument Flight Rules (“IFR”). Mr. Hicks, Shelly Kate Hicks, and their two children sustained fatal injuries.

      Defendant filed a Daubert motion to limit the testimony of Plaintiffs’ accident reconstruction expert John Bloomfield.

      Avionics Expert Witness

      John W. Bloomfield is the President and owner of Bloomfield Research and Development and am the holder of twelve United States patents in the disciplines of electronics, robotics, avionics, medical electronics, ultrasonics, precision spread spectrum radio ranging, battlefield communications, cellular digital software, and electronic toys.

      He holds an engineering degree in systems engineering and has 35 years of experience in aircraft electrical and avionics system. He has also been involved in the investigation of hundreds of aircraft accidents.

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

      Discussion by the Court

      Qualification

      First, the Defendant argued that Bloomfield opined regarding “metallurgical issues,” namely, that steel debris caused engine failure, despite being unqualified to do so. However, the Court has reviewed Bloomfield’s qualifications and is satisfied that, based on his extensive experience, which includes investigating numerous aircraft accidents and examining component parts, he is qualified to opine that steel debris caused the engine failure.

      Reliability

      Second, the Defendant argued that Bloomfield’s opinion that steel debris caused a loss of torque is untested and entirely speculative and therefore unreliable. Plaintiffs responded that Bloomfield explained he could not test the debris because it was not preserved, and testing could not be performed under substantially similar circumstances. He instead based his opinion regarding the presence and size of steel debris on the gouges left on the crankshaft.

      Bloomfield explained that any debris that was between the gear and the crankshaft was lost when the engine was taken apart and wiped during the inspection. And he testified that it was not possible to replicate his theory of the crash in a testing environment.

      Though Bloomfield’s failure to test his contamination theory is not determinative, this Court is not absolved of its gatekeeping function.

      The Court found that Bloomfield met the Daubert standard. Bloomfield explained why, based on a variety of evidence including key indicators used by other accident investigators, he concluded that the helicopter’s engine was not under power when the helicopter crashed.

      He then explained, using other case studies for reference, why he believed the dowel pin in the engine fractured not upon impact but during flight, causing a cessation of engine power.

      Finally, he discussed how the fractured dowel pin was caused by the loose gear bolt found in the engine, which could in turn be caused by a loss of torque from debris on the crankshaft, and how the presence of such debris was evinced by score marks on the gear face and crankshaft face.

      Helpfulness

      Defendant argued that Bloomfield’s criticism of the National Transportation and Safety Board’s investigation, particularly his discussion of the NTSB’s failure to preserve alleged contaminants, is neither reliable nor helpful.

      Defendant is concerned that Plaintiffs are trying to backdoor in a spoliation claim at trial. The Court previously denied Plaintiffs’ motion for a finding of spoliation and sanctions based upon Defendant’s alleged failure to preserve contaminants on the engine. The Court is prepared to sustain objections to any attempts to circumvent this Court’s ruling, including any argument that Defendant intentionally destroyed evidence. However, Plaintiffs’ experts may, of course, discuss the lack of physical evidence of contamination and their inability to perform certain tests on the engine because it was cleaned during the investigation.

      To that end, this Court is satisfied that Bloomfield can also reliably opine as to the way the engine was handled after the crash. Bloomfield either personally observed the instances he described, or he explained how, based on his training and experience, these parts are typically handled during the inspection process.

      Held

      The Court denied the Defendant’s Daubert motion to limit the testimony of Plaintiffs’ accident reconstruction expert John Bloomfield.

      Key Takeaway

      The Court is satisfied that Bloomfield has demonstrated his opinion is reliable. To the extent Defendant wishes to challenge Bloomfield’s conclusions and their bases, vigorous cross-examination, presentation of contrary evidence, and careful instruction on the burden of proof are the traditional and appropriate means of attacking shaky but admissible evidence.

      Case Details:

      Case Caption: Law V. Avco Corporation
      Docket Number: 1:24cv3
      Court Name: United States District Court for the Northern District of Florida, Gainesville Division
      Order Date: November 04, 2025
    3. Economics Expert Was Allowed to Opine on Recidivism

      Economics Expert Was Allowed to Opine on Recidivism

      Plaintiff John Doe brought facial and as-applied constitutional challenges to the reporting requirements contained in Arizona’s sex offender registry statutes. Under Arizona’s statutory scheme, Doe is required to register as a
      sex offender for life.

      Intervenor-Defendants Warren Petersen and Ben Toma retained Dr. John Lott as an expert witness. Plaintiff filed a motion to exclude the testimony of Lott in whole and in part.

      Economics Expert Witness

      John Richard Lott holds a Ph.D. in economics and served as the chief economist for the United States Sentencing Commission. Presently, Lott is the President of the Crime Prevention Research Center, a role he has served in since 2021.

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

      Discussion by the Court

      Doe argued that Lott is not qualified to offer the opinions in Lott’s report because Lott has had “no training in criminology, sociology, psychology or any related fields,” possesses “no certification or formal training in the treatment or assessment of sex offenders,” and “has never been qualified by another court as an expert in general recidivism, sexual offense recidivism, or any other topic relevant to this case.” The Court disagreed.

      Lott possesses some background in statistics and has been retained by Intervenor-Defendants to conduct a statistical analysis; Lott thus possesses the “minimal foundation of knowledge, skill, and experience” necessary to be qualified as an expert under Rule 702.

      Held

      The Court denied Doe’s motion to exclude the testimony of Dr. John Lott in whole and in part.

      Key Takeaway

      Lott possesses no discernible specialized knowledge or expertise in the area of sex crimes, sex offender recidivism, or recidivism more broadly. Nonetheless, Doe’s arguments for excluding Lott’s testimony from this matter ultimately go to the weight, not the admissibility, of Lott’s testimony.

      Case Details:

      Case Caption: Doe V. Sheridan
      Docket Number: 2:23cv1938
      Court Name: United States District Court, Arizona
      Order Date: November 07, 2025