Expert Witness Profiler

Blog

  • Psychology Expert’s Opinions About the Individual Health Impacts of PCB Exposures Admitted

    Psychology Expert’s Opinions About the Individual Health Impacts of PCB Exposures Admitted

    Plaintiffs Josepha Austin, Robin Cruz, Gordana Pobric, and Jennifer Haselman brought this action claiming harm resulting from their exposure to polychlorinated biphenyls (“PCBs”).

    Defendants Monsanto Company, Bayer CropScience, L.P., Solutia, Inc., and Pharmacia L.L.C. (collectively “Monsanto”) filed a motion to exclude the testimony of Dr. Gayle Morse. Plaintiffs intended to call Morse to testify about cognitive injuries they allegedly suffered as a result of PCB exposures.

    Psychology Expert Witness

    Gayle Morse is a licensed psychologist and neuropsychologist in New York State. She holds a doctorate in counseling psychology and is a tenured professor at Russell Sage College, where she serves as the internship director of the mental health counseling and community program. She currently teaches psychology courses and maintains a private clinical practice.

    Morse has been involved in PCB research since 1994. Her work has included multiple studies on the impacts of PCBs on members of the Akwesasne Mohawk Tribe. That work reportedly included the neuropsychological testing of hundreds of people who were exposed to PCBs. Morse has authored several peer-reviewed articles on the effects of PCB exposure on human populations, and has testified that one of her projects revealed evidence of adverse effects of PCBs on human neuropsychological functioning.

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

    Discussion by the Court

    In her expert report, Morse concluded, “with a reasonable degree of medical/scientific certainty, that the above exposures to PCBs are consistent with [Plaintiffs’] injuries and that said PCB exposures were a significant contributing cause to their cognitive conditions.”

    Monsanto’s challenge to Morse focuses on her qualifications and the reliability of her conclusions.

    Qualifications

    With respect to her qualifications, Monsanto noted that Morse spends most of her professional time working in academia, with her clinical practice occupying only one day per week. Within her clinical practice, she generally treats people with severe psychopathology such as schizophrenia or long-term trauma. In her deposition testimony, she distinguished her practice from that of a neuropsychologist.

    She also testified that she performs neuropsychology evaluations approximately twice a year. Monsanto criticized Morse for not being board certified in neuropsychology. The Court found that board certification is only relevant in the context of an expert’s other qualifications.

    Morse concedes that she is not a neuropsychologist, and that she only conducts such testing occasionally.

    The neuropsychological tests in this case were administered by Dr. Eric Mart. Monsanto did not challenge his qualifications to perform and interpret such testing.

    The Court held that Morse is not testifying outside her area of expertise. Nor is she merely relaying the opinion of Mart. Indeed, there is no suggestion that Mart formed any sort of opinion regarding the impact of PCBs. Instead, it is Morse who independently reviewed the test results and formed an opinion about how those results align with her knowledge about the potential impacts of PCB exposure.

    Reliability

    Morse reviewed not only Mart’s test results, but also the reports of Plaintiffs’ experts Kevin Coghlan, who generated data regarding PCB levels at Burlington High School, and Dr. Paul Rosenfeld, who opined on the level of hazard resulting from those PCB levels. She further reviewed the report generated by Dr. David Carpenter, with whom she has worked in the past and who offered his opinion as to general causation. In the course of preparing her own report, Morse interviewed each Plaintiff. Applying her professional knowledge, Morse developed opinions about the individual health impacts of PCB exposures. Her report explicitly states that she considered other possible causes of Plaintiffs’ conditions, and that she reached her conclusions with a reasonable degree of medical or scientific certainty.

    Monsanto is critical of Morse’ use of Plaintiffs’ “premorbid functioning” as a tool for determining that PCBs played a role in causing their conditions.
    In her deposition, Morse explained that she was not able to rule out the impact of all other factors, such as one Plaintiff’s tuberculosis or another’s thyroid condition, since she is not a physician.

    Aside from those issues, she was able to compare the Plaintiffs’ abilities and achievements prior to their time at Burlington High School with their abilities after their respective PCB exposures, note the differences, and opine as to cause. Her caveats about certain medical conditions did not undermine her methodologies, and instead left room for cross-examination and argument regarding her conclusions.

    Monsanto’s final criticism of Morse is that she did not identify the dose at which PCBs could be expected to cause the conditions discussed in her report. However, more than one expert in this case has offered the opinion that the dose-response relationship for PCBs may be nonlinear, and even non-threshold.

    Held

    The Court denied Monsanto’s motion to exclude the testimony of Gayle Morse, Ph.D.

    Key Takeaway:

    Plaintiffs have shown by a preponderance of the evidence that Morse is qualified and that the data on which she is relying, which includes both neurological testing and PCB exposure estimates, is sufficient and reliable. Moreover, Plaintiffs have carried their burden of showing that Morse is applying reliable methodologies based on her significant experience with PCB studies, that she reliably applied accepted principles and methodologies to the facts of this case, and that her testimony will assist the trier of fact.

    Case Details:

    Case Caption: Austin V. Monsanto Company
    Docket Number: 2:23cv272
    Court Name: United States District Court, Vermont
    Order Date: December 01, 2025
  • Vocational Evaluation Expert Allowed to Opine on Lost Earning Capacity

    Vocational Evaluation Expert Allowed to Opine on Lost Earning Capacity

    This litigation arises from Plaintiff Raymond Flanks’ (“Plaintiff”) wrongful conviction for first-degree murder in 1985. Plaintiff alleged that the Orleans Parish District Attorney’s Office (“OPDA”) secured his wrongful conviction in violation of his constitutional rights by withholding material exculpatory evidence.

    Brandy Bradley is a vocational evaluator retained by Plaintiff to estimate the earnings he lost while incarcerated. Defendants contended that Bradley’s proposed testimony is unreliable and irrelevant.

    Vocational Evaluation and Rehabilitation Expert Witness

    Brandy E. Bradley is a rehabilitation counselor licensed by the State of Louisiana. She is also a certified life care planner and certified vocational evaluator; and she is a vocational expert for the Department of Health and Human Resources, Social Security Administration, and Office of Disability Adjudication and Review. She holds an undergraduate degree in psychology, a graduate degree in rehabilitation counseling, and a post-graduate certification in life care planning.

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

    Discussion by the Court

    Based on Plaintiff’s education during his incarceration and his post-incarceration vocational testing scores, Bradley opined that Plaintiff “could have established a career path had he not been incarcerated.”

    Bradley assumed that had Plaintiff not been convicted of first-degree murder in 1985, he would have been released on parole in 1991, after serving half of his fifteen-year sentence for a separate armed robbery conviction. Bradley concluded that Plaintiff “had the potential to earn” wages equal to the annual mean wage for Black males with GEDs/high school diplomas from 1991 to 2022.

    Bradly provided two alternative lost earning capacity calculations––$393,692.00 if Plaintiff had earned minimum wage from 1991 through 2022 or $975,578.00 if Plaintiff had earned the annual mean wage for a Black male with a GED or high school diploma.

    Defendants’ Arguments in Support of the Motion

    Defendants argued that it is not reasonable to assume that the Plaintiff would have maintained continuous, full-time employment at any wage, absent evidence that the Plaintiff had obtained and maintained such employment before the injury complained of in his lawsuit.

    Next, Defendants argued that the calculation of lost wages is unreliable because it does not deduct the expenses Plaintiff would have incurred had he not been out of prison earning minimum wage.

    Finally, Defendants argued that the calculation of lost wages is unreliable and irrelevant because it is based on the unreliable premise that Plaintiff would have been released on good time parole after serving 7.5 years in prison for the armed robbery conviction.

    Analysis

    The Court held that Plaintiff should be free to make an argument to the jury that he could have earned more than his pre-incarceration income suggests.

    Presumably, Defendants will present testimony to show that Plaintiff would have earned even less than $393,692.00, because he was not earning minimum wage at the time of his incarceration. Defendants can question Bradley on this issue, and they are free to present evidence showing how much Plaintiff earned in the years preceding his incarceration. If the jury finds for Plaintiff on liability, it will then be for the jury to decide how much Plaintiff would have earned had he not been wrongfully incarcerated.

    Consistent with prior cases on this issue, the Court will require Bradley to amend the report to reduce the lost wages/benefits numbers to account for expenses that Plaintiff would have sustained had he been out of prison.

    Finally, Defendants contended that Bradley’s testimony should be excluded because it is based on the incorrect premise that Plaintiff would have been released from prison in 1991 on the armed robbery conviction.

    The Court will instruct the jury on the applicable law regarding “good time” release. If the jury finds for Plaintiff on liability, it will then be tasked with the factual determination on when Plaintiff would have been released from prison absent the allegedly wrongful conviction. Based on that determination, the jury will then decide how much income Plaintiff lost from the time he would have been released until his actual release in 2022. This is not a basis for exclusion of Bradley’s testimony.

    Held

    The Court denied the Defendants’ motion to exclude the testimony of
    Brandy Bradley.

    Key Takeaway:

    The Defendants have not shown that Bradley’s opinions were so irrelevant and unreliable as to require exclusion pursuant to the Court’s gatekeeping obligation under Daubert and its progeny.

    Case Details:

    Case Caption: Flanks V. City Of New Orleans
    Docket Number: 2:23cv6897
    Court Name: United States District Court, Louisiana Eastern
    Order Date: December 01, 2025
  • Economics Expert’s Updated Damages Calculations Admitted

    Economics Expert’s Updated Damages Calculations Admitted

    Plaintiff Misty Blanchette Porter was previously employed as a physician in the Reproductive Endocrinology and Infertility (“REI”) Division within Dartmouth Health’s Department of Obstetrics and Gynecology (“OB/GYN”).

    After Dartmouth Health made the decision to shut down the REI Division entirely and to terminate all three physicians employed therein—including Porter—Porter filed suit against Dartmouth Health citing disability discrimination.

    Dartmouth Health argued that the testimony of Porter’s damages expert, Dr. Robert L. Bancroft, should have been excluded due to untimely disclosure under Rule 26.

    Economics Expert Witness

    Robert L. Bancroft holds a bachelor’s degree in economics from the University of Vermont (“UVM”); a Master of Science in agricultural economics from UVM; and a Ph.D. in agricultural economics from Purdue University.

    From June 1979 until August 1981, Bancroft worked for the United States Department of Agriculture to develop an econometric forecasting model to forecast farmers’ participation in certain government programs and to provide testimony and research to the U.S. House of Representatives. Next, Bancroft began work as an assistant professor in the Department of Agriculture and Resource Economics—later renamed the Department of Community Development and Applied Economics—at the University of Vermont in August 1981. Bancroft continued as an assistant professor of economics until 1991, when he became an adjunct professor. He worked as an adjunct professor of economics until 1996.

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

    Discussion by the Court

    Rule 26

    Dartmouth Health contended that the Court erred by admitting testimony and exhibits offered by Porter’s expert damages witness, Bancroft, because Porter failed to timely disclose several of his expert opinions under Rule 26.

    The Court found that the timing of the disclosure of Bancroft’s March 19, 2025, supplemental report did not warrant a new trial. The March 2025 supplemental report was a direct response to defense counsel’s cross-examination of Bancroft at a hearing on Dartmouth Health’s motion to exclude Bancroft from testifying as an expert witness at trial.

    Cross-examination elicited that Bancroft was unaware of certain information relevant to his calculations. Bancroft subsequently updated his report on March 19 to incorporate this new information. Dartmouth Health plainly knew this information before Bancroft issued his March 19 report, as defense counsel raised the issue at the evidentiary hearing. 

    Moreover, Bancroft did not change the substance of his opinion. He used the same methodology in his March supplemental report as in his prior reports, changing only the inputs to produce updated damages calculations.

    The Court did not share Defendants’ view that Bancroft issued his corrective March 2025 report because his testimony at the March 12 evidentiary hearing revealed that his August 2024 report “had not included key facts and assumptions . . . such as Porter’s promotion to full professor in July 2023 and her most recent earnings from UVMMC at a higher rate of pay than what Bancroft had projected.”

    Rule 37

    Even if the disclosures were untimely, admitting Bancroft’s testimony was not error because the disclosures were substantially justified or harmless under Rule 37.

    The first factor—the willfulness of the non-compliance regarding the March 2025 report and the reason for the noncompliance—did not weigh definitively in either party’s favor. Porter knew well before March 2025 that she had received a $7,698 tuition credit for her son’s undergraduate education at UVM in 2019, and Bancroft could have included that information in his August 2024 report. On the other hand, Dartmouth Health knew that it had approved salary freezes in 2020 and 2021, and Dartmouth Health did not allege that Porter or Porter’s expert had that information until March 2025.

    The efficacy of lesser sanctions and the possibility of a continuance weigh against excluding Bancroft’s testimony. Dartmouth Health’s proposed alternative—introducing its own expert witness to rebut Bancroft’s supplemental report—was simply not feasible only four days before a three-week trial.

    The duration of noncompliance factor was inconclusive. Although Porter was aware of some information that impacted her expert’s damages calculations well in advance of the March 2025 report, other information was only in the possession, custody, or control of Dartmouth Health until the March evidentiary hearing. Bancroft submitted his updated report one week after the evidentiary hearing.

    The Court is unaware of any previous warning to Porter that an untimely supplemental expert report could result in exclusion of the expert witness.

    Moreover, Dartmouth Health already had a significant amount of the updated information Bancroft relied on for his March 2025 supplemental report. It is difficult to conceive how admitting the March 2025 report, or Bancroft’s testimony consistent with that report, prejudiced Dartmouth Health given that the report estimated substantially lower damages figures than any of Bancroft’s previous reports.

    Held

    The Court held that the relevant factors weighed against excluding Robert Bancroft’s testimony.

    Key Takeaway:

    Without Bancroft’s testimony, Porter would have been severely disadvantaged in quantifying her claimed economic damages. Such a sanction would have been disproportionate to the alleged noncompliance given that the late disclosure had a reasonable basis; Bancroft’s methodology did not change from one report to the next, and Bancroft’s final report substantially reduced Porter’s estimated damages.

    Case Details:

    Case Caption: Blanchette Porter V. Dartmouth Hitchcock Medical Center
    Docket Number: 2:17cv194
    Court Name: United States District Court, Vermont
    Order Date: November 26, 2025
  • Palliative Care Expert’s New and Expanded Opinions on Facility Neglect Admitted

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

    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.

    Defendants Koelsch Senior Communities, LLC (“Koelsch”), and Billings Partners, LLC d/b/a Canyon Creek (“Canyon Creek”) filed a motion in limine to exclude the Plaintiffs’ expert Scott Bolhack, M.D.’s undisclosed expert opinions and limit his testimony to only what was timely disclosed in his expert disclosure.

    Palliative Care Expert Witness

    Scott Matthew Bolhack, M.D. is board certified in internal medicine and hospice and palliative medicine with additional credentials as a Certified Wound Specialist Physician and a Certified Medical Director in long-term care. He has experience as a medical director for skilled nursing homes, assisted living facilities, hospices, home health agencies and wound centers. He has spoken on many topics nationally and has presented over 35 scientific posters in the areas of wound care, quality improvement, and post-hospital care.

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

    Discussion by the Court

    Defendants first sought to exclude three categories of material Bolhack relied on in forming his opinions, but did not disclose until his deposition. Those categories include: (1) documents available to Plaintiffs before the expert disclosure deadline but not provided to Bolhack until one week before his deposition; (2) documents available to Plaintiffs after the expert disclosure deadline but not provided to Bolhack until one week before his deposition; and (3) documents available to Bolhack before the expert disclosure deadline but only relied on after receiving the additional documents from Plaintiffs’ counsel one week before his deposition.

    Defendants next sought to exclude Bolhack from relying on the new opinions found in his Deposition Notes, which were provided to Defendants for the first time at his deposition.

    A. Federal Rule of Civil Procedure 26

    1. Documents Available to Plaintiffs Before the Expert Disclosure Deadline but not Provided to Bolhack Until One Week Before his Deposition

    All material in the first category, except for one employee declaration, was available to the parties before the expert disclosure deadline.

    Yet, Plaintiffs did not provide the material to Bolhack until approximately one week before his deposition. This means Bolhack received the material almost three months after his initial disclosure and one month after the close of discovery.

    Here, the Court found no reason justifying Plaintiffs’ decision to withhold the first category of material from Bolhack when that material was available before the expert disclosure deadline. Because Bolhack ultimately relied on the material to form his opinions, Plaintiffs failed to timely and adequately disclose under Rule 26(a).

    2. Documents Available to Plaintiffs After the Expert Disclosure Deadline but not Provided to Bolhack Until One Week Before his Deposition

    Here, the parties learned of the material in this second category after the initial disclosure deadline.

    Therefore, Plaintiffs duty to supplement arose under Rule 26(e) when they learned that Bolhack’s Initial Disclosure was either incomplete or incorrect based on the new information. Plaintiffs’ contention that they “need not supplement when information [was] made known in the discovery process” has no merit here because the information in this second category exceeds the scope of Rule 26(e), that is—”correcting inaccuracies or filling the interstices of an incomplete report.”

    As the Court has discussed, Bolhack used this second category of material to revise, add to, and create new opinions. Even if Plaintiffs are now conceding the Initial Disclosure was inaccurate or incomplete, they have failed to show what part of the Initial Disclosure needed to be corrected or filled in. As such, the Court found that the additional material in this category was not a proper supplementation as allowed under Rule 26(e)(1).

    3. Documents Available to Bolhack Before the Expert Disclosure Deadline but Only Relied on After Receiving the Additional Documents from Plaintiff’s’ Counsel One Week Before his Deposition

    The final category of material Defendants sought to exclude consisted of governmental regulations and medical literature Bolhack admitted to reviewing only after he received and reviewed the preceding two categories of material.

    The scientific articles were published between 1993 and 2022, and the governmental regulations were both publicly available and long-standing. Therefore, they would have been available for review before the expert disclosure deadline.

    Again, Bolhack did not disclose these regulations or articles in his Initial Disclosure and therefore they were untimely disclosed under Rule 26(a). And unless Plaintiffs now concede Bolhack’s Initial Disclosure was inaccurate or incomplete, the introduction of this new material was not proper supplementation as contemplated by Rule 26(e).

    4. Bolhack’s Deposition Notes and Opinions

    After receiving and reviewing the three categories of undisclosed material, Bolhack compiled his Deposition Notes. As a result, his Notes—by his own admission—contain “a host of opinions” not found in his Initial Disclosure.

    Bolhack’s new and expanded opinions pertain to causation of death, facility neglect and causality, expanded event timelines, COVID-19 response, pressure wound management and nutritional declines, hospice care initiation, and detailed rebuttal of other experts’ testimony.

    For example, as to causation and neglect, the Deposition Notes surpass the summary-level conclusions initially disclosed. At first, Bolhack detailed causation opinions regarding all three decedents, with references to multiple contributing factors beyond the primary disease listed on each death certificate, but with no specific references to Canyon Creek’s standard of care breach. By contrast, the Deposition Notes include more detailed and pointed attributions of death and decline to Canyon Creek’s failure in monitoring, intervention, and institutional processes, including explicit citations to regulatory standards.

    Likewise, Bolhack’s Notes introduced new criticisms of Canyon Creek’s pandemic response. His new opinions connect pandemic failures to patient outcomes in ways that were largely absent from his Initial Disclosure.

    Finally, unlike his Initial Disclosure, Bolhack’s Notes challenged opposing expert testimony with new opinions, stating he was not confident their COVID-19 severity assessment was correct, and critically questions whether appropriate processes were in place. His detailed critiques of the testimony and opinions of opposing experts, referencing both factual disagreements and regulatory mandates, are absent from the Initial Disclosure.

    It is obvious—by Bolhack’s own admission and after review of the two reports—that the Deposition Notes are different from, rather than supplemental to, the opinions contained in his Initial Disclosure.

    B. Federal Rule of Civil Procedure 37

    1. Substantially Justified and Harmless

    Plaintiffs first attempted to justify Bolhack’s late disclosure by claiming they complied with Defendants’ subpoena after the parties agreed expert notes were not discoverable.

    Plaintiffs further argued that the late disclosure was harmless because Defendants have now known about Bolhack’s opinions for over a year, declined to follow up, and never tried to re-open the deposition or supplement their own experts’ reports.

    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 Bolhack’s new opinions at his deposition. True, Plaintiffs complied with Defendants’ subpoena. However, had Defendants not subpoenaed Bolhack, they may not have learned about the new materials Bolhack relied on or his new opinions until trial.

    The record showed the additional material Bolhack relied on was largely available before the disclosure deadline. Plaintiffs offered no reason why it was not provided to Bolhack before his Initial Disclosure, and therefore, the late disclosure of the documents and Bolhack’s new opinions was not justified.

    The Court next rejected Plaintiffs’ contentions that Defendants “sat on their hands” in bringing the instant motion. The procedural record reflected Defendants’ timely pursuit of relief consistent with the Court’s directive regarding the timing of motions in limine.

    2. Sanctions

    Here, Plaintiffs’ inadequate disclosure was neither substantially justified nor harmless. However, 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 Bolhack’s late disclosure 14 months ago. Second, expert testimony is essential to litigating the parties’ case; as such, there are less drastic sanctions available than striking portions of Bolhack’s opinions.

    The jury should be allowed to weigh the entirety of Plaintiffs’ experts’ opinions.

    Therefore, the Court elected to impose the lesser sanction of allowing Plaintiffs to file Bolhack’s supplemental expert report and allowing Defendants to reopen Bolhack’s deposition. The parties may conduct this deposition by Zoom or other remote means, and Plaintiffs shall bear the reasonable costs of conducting this deposition.

    Held

    The Court denied Defendants’ motion in limine to exclude the Plaintiffs’ expert Scott Bolhack, M.D.’s undisclosed expert opinions and limit his testimony to only what was timely disclosed in his expert disclosure.

    Key Takeaway:

    Sanctions which interfere with the litigants’ claim or defenses violate due process when they are imposed merely for punishment of an infraction that did not threaten to interfere with the rightful decision of the case.

    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: November 13, 2025
  • Law Enforcement Expert Was Not Allowed to Opine on Trafficking at Hotels

    Law Enforcement Expert Was Not Allowed to Opine on Trafficking at Hotels

    This case arises under the Trafficking Victims Protection Reauthorization Act (TVPRA), which provides victims of sex trafficking a civil remedy against the perpetrators and beneficiaries of their trafficking. Plaintiff C.L.F. filed this action to recover for alleged harm she experienced from being trafficked at a Motel 6 in Wichita, Kansas, that she claims was owned and operated by the Defendants.

    On August 21, 2025, C.L.F. filed the motion sub judice, seeking to exclude as irrelevant the testimony of Defendants’ designated law-enforcement expert witness Bill Woolf.

    Law Enforcement Expert Witness

    William “Bill” Woolf has spent over 15 years of experience in law enforcement, specializing in the investigation of human trafficking, organized criminal enterprises, narcotics, and gang-related crime.

    He has conducted extensive fieldwork in identifying, investigating, and dismantling human trafficking networks, with a focus on both sex trafficking and labor trafficking operations occurring in a variety of settings, including hospitality environments.

    Woolf is the Principal and Founder of The Woolf Group, a national consulting firm providing expert guidance on human trafficking prevention, investigation, training, and public policy.

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

    Discussion by the Court

    C.L.F. asked the Court to exclude all four opinions offered by Woolf. Namely, Woolf’s opinions that:

    (1) “There is no evidence that trafficking involving CLF was identified or interdicted by law enforcement during the relevant period;”

    (2) “Hotel staff are not trained, equipped, or authorized to investigate or intervene in suspected trafficking operations;”

    (3) “In transient lodging environments, the investigative and intervention burden for human trafficking rests with law enforcement, not hotel personnel;” and

    (4) “It is unreasonable to retroactively impose a higher duty of detection on hotel staff than the standard applied by law enforcement at the time.”

    C.L.F. claimed that “all of Woolf’s opinions are red herrings that draw the jury’s attention to topics that have no bearing on the actual issues that must be decided in this case.”

    Opinion 1

    Woolf may not tell the jury there was “no evidence that trafficking involving C.L.F. was identified or interdicted by law enforcement during the relevant period.” This is irrelevant to understanding whether hotel staff knew or should have known of sex trafficking at the Wichita Motel 6. It is also misleading. Hearing that police officers had “frequent engagement with the subject properties” and that they made no reports or arrests for sex-trafficking related crimes would lead a juror to conclude that such conduct was absent. That distracts the jury from the pertinent inquiry. Numerous arrests for sex trafficking might put hotel employees on notice, but that logic does not follow from a total absence of arrests. Law enforcement may not have arrested anyone for trafficking at the Wichita Motel 6, but that in no way precludes hotel management and staff from being aware of ongoing sex-trafficking-related activity.

    As such, the Court struck Woolf’s opinion as irrelevant and misleading.

    Opinion 2

    The Court struck Woolf’s second opinion as misleading. Investigating and/or intervening in human trafficking is not an element of the TVPRA and to suggest that Defendants’ employees were not trained or able to investigate, identify, or interdict trafficking injects elements into C.L.F.’s burden of proof that simply are not there. All that is required for C.L.F. to show is that Defendants’ employees were negligently aware of sex-trafficking-related activity on the property.

    Opinion 3

    The jury cannot hear Woolf’s third opinion. It would tell the jury that, since hotel staff lack the “access to confidential intelligence, interagency data, investigative tools, and legal mechanisms such as warrants and subpoenas” that police officers have, hotel staff are unable to “reliably assess” potential trafficking red flags.

    This would seriously undercut the jury’s factfinding role. As said, hotel staff cannot escape imputing knowledge from their own observations of sex-trafficking-related activity just because they lack military-grade investigative tools. A janitor’s inability to petition a judge for an arrest warrant has no bearing on his awareness of sex trafficking if there were observable signs of trafficking in the hotel hallways. The jury, who “is solely responsible for determining the weight and credibility of the evidence,” should assess how Defendants’ staff interpreted those signs without assessing how a police officer would react.

    Further, pointing out hotel staff’s lack of crime-prevention tools might mislead the jury to think that the TVPRA excuses liability where a defendant is unable to prevent sex trafficking. As the parties know, making that suggestion to the jury would be wholly inappropriate because “the TVPRA does not impose an affirmative duty to police and prevent sex trafficking” (nor excuse sex-trafficking liability because no duty to prevent exists). The relevant inquiry is whether hotel staff knew of trafficking, not if they prevented, or attempted to prevent, it. 

    Opinion 4

    Woolf’s fourth opinion is simply a summary of his already discussed testimony. His claim that it is “unreasonable to retroactively impose a higher duty of detection” on hotel staff than law enforcement highlights the irrelevance of his other opinions. Discussion of law enforcement’s knowledge or lack thereof regarding trafficking at the Wichita Motel 6 has no effect on that of hotel management and staff. Referring to it would only mislead the jury. Woolf’s testimony appears designed to imply that Defendants were unaware of sex trafficking because law enforcement, with all its law-enforcement techniques, was also unaware. While sensible to think that a layperson would not detect an ongoing crime if a police officer in the same situation could not, that analogy is “non-helpful” here.

    The standard is whether hotel staff knew of sex trafficking at their hotel. As explained, hotel staff are in a much different position than police officers to observe the day-to-day happenings at a hotel. The ways in which law enforcement and hotel staff acquire knowledge of sex trafficking at a hotel are completely different and to conclusively suggest to the jury that what was not observable to law enforcement was not observable to hotel staff is both untrue and unhelpful.

    Rebuttal Opinions

    Defendants pointed out that Woolf also offered rebuttal testimony to C.L.F.’s experts, and that C.L.F.’s motion did not request those rebuttal points to be excluded. C.L.F. responded that, if the Court excludes Woolf’s opinions, then it should also exclude his rebuttal opinions.

    All four opinions asserted that it would be unreasonable to find that hotel staff were aware of sex trafficking at the Wichita Motel 6 because law enforcement, with its greater resources, tools, and training, was not. As explained, such testimony would only confuse the jury.

    Rebuttal Opinion 2 responded to C.L.F.’s expert witnesses’ claims that hotel training was inadequate by pointing out that no industry standards about sex-trafficking awareness, such as the DHS Blue Campaign Hospitality Toolkit, existed until after this case’s relevant trafficking period.

    The opinion also pointed out how “assertions by [C.L.F.’s law-enforcement expert] Christi Decouflé that G6 policies actively discouraged reporting to law enforcement are not substantiated by the record.” But this is straightforward impeachment. It did not help the jury to have Woolf provide such testimony. Impeaching a witness by highlighting inconsistencies between their testimony about documents and facts contained in and relating to those documents does not require specialized knowledge, nor even a live witness; instead, that is the role of counsel.

    This Ruling Remains Good for Both the Goose and the Gander

    Woolf’s testimony could only muddle things, as he would not testify about red flags observable or known to hotel employees. Instead, he wants to advise the jury on what law enforcement would or would not have known. This would not help the jury.

    While Woolf’s testimony goes to Defendants’ actual or constructive knowledge about the trafficking, it is inappropriate as compared to other experts.

    Decouflé’s testimony here is based on Defendants’ own policies, guests’ online reviews, and what potential sex-trafficking-related facts the hotel workers, not police, saw during the relevant time. She would testify to hotel-staff knowledge based on hotel-staff observations while Woolf would compare hotel-staff knowledge and training to police-officer knowledge and training. For a jury deciding what the hotel staff knew or should have known, the former is helpful; the latter is not. Woolf’s testimony is irrelevant.

    Held

    The Court granted Plaintiff’s motion to strike or exclude the testimony of Bill Woolf.

    Key Takeaway:

    The perspective of a trained law enforcement officer experienced in identifying, investigating, and intervening in cases of human trafficking—even within hospitality settings—would not help the jury understand or determine whether G6’s management or staff knew, or should have known, that sex trafficking was occurring at the Wichita Motel 6.

    While Woolf indicated that he considered “the observable signs and behaviors that might have been available to hotel staff,” his opinions address only what law enforcement would understand and/or do in response to those observations.

    Please refer to the blog previously published about this case:

    Psychology Expert’s Opinion on Social-Media-Facilitated Sex Trafficking Admitted

    Case Details:

    Case Caption: Doe C.L.F. V. G6 Hospitality, LLC
    Docket Number: 1:23cv303
    Court Name: United States District Court, Texas Eastern
    Order Date: November 17, 2025
  • Forensic Engineering Expert’s Testimony on Brake Levers Admitted

    Forensic Engineering Expert’s Testimony on Brake Levers Admitted

    Plaintiff Matthew Hartley sued Defendants Sunbelt Rental Inc. and Custom Equipment LLC to recover for personal injuries he sustained during a jobsite incident on June 14, 2021.

    Plaintiff alleged that on June 14, 2021, he “attempted to move a Sunbelt Rentals Hy-Brid Lift HB-1030 down a ramp when suddenly and without warning it began to rapidly roll down the slope of the ramp despite no effort on his part to power the lift forward.” He further alleged that the lift, which was manufactured by Custom Equipment, LLC, “rolled uncontrollably into a concrete wall at a rapid rate of speed” causing “debilitating physical injuries” and a variety of economic and noneconomic harms.

    Plaintiff retained Craig Sylvester, a forensic engineering expert, to determine the “root cause” of the accident. According to Sylvester, “the root cause of the incident on June 14, 2021 was a mis-wired emergency stop button, as well as the placement of one or both of the parking brake levers at the rear of the machine in an intermediate position.”

    Defendant Custom Equipment filed a motion to strike certain expert opinions and limit testimony of disclosed expert Craig Sylvester.

    Forensic Engineering Expert Witness

    Craig A. Sylvester is a former U.S. Navy mustang officer and licensed mechanical engineer with more than 25 years of experience as an operator, maintainer, designer, and inspector of industrial equipment around the world. Sylvester’s expertise in industrial systems is built on his early work performing component-level repairs as an electronics technician, along with formal education in manufacturing and mechanical engineering, and naval architecture.

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

    Discussion by the Court

    Parties’ Arguments

    Defendant requested the Court “exclude the portions of Sylvester’s opinions that are untimely, speculative and unhelpful to the jury.”

    Defendant argued that exclusion is warranted because Sylvester’s: (1) supplemental opinions on electromagnetic braking assistance, back emf braking assistance, and arc suppression circuits are untimely and unhelpful to the jury; (2) opinions on the intermediate position of the brake levers are speculative; (3) opinions on the parking brake’s holding torque are unhelpful to the jury; and (4) opinions that the pre-start inspection checklist failed to adhere to the ANSI A92.22 standards are unhelpful to the jury.

    Plaintiff contended, and Defendant accepted, that “Sylvester has no intention of testifying that the HB 1030 should have included ‘electromagnetic,’ ‘back emf’ or an ‘arc suppression circuit’ at the time of trial.” The Court thus found these admissibility questions to be moot. Plaintiff also stated that Sylvester “will not be testifying regarding [the holding torque] document” and that the “[ANSI A92.22] standards, which were adopted after the manufacture and sale of the HB 1030, would not apply to [the unit at issue.]” As Defendant did not challenge the admissibility of testimony by Sylvester that “industry standards would include a pre-start inspection of the braking system as a matter of common sense and industry standards” nor do they otherwise challenge Plaintiff’s concessions on these issues, the Court likewise found these admissibility questions moot.

    Court’s Decision

    The Court concluded that Sylvester’s opinions on the intermediate position of the brake levers “both rests on a reliable foundation and is relevant to the task at hand.”

    As for relevancy, the Court found that Sylvester’s opinions on the intermediate position of the brake levers will “assist the trier of fact” to determine the root cause of the June 14, 2021 incident. As the root cause of the incident is “a fact in issue,” Sylvester’s testimony satisfied the standard for relevancy. The Court also concluded that Sylvester reviewed numerous sources of information, utilized reliable principles and methods of forensic engineering, and reliably applied said principles and methods to the facts of the case.

    The Court noted that Sylvester “considered seven categories of evidence in reaching his conclusion, only one of which was a document generated during the course of BN Builders investigation, which occurred shortly after the incident in question.” As a result, the Court declined to exclude Sylvester’s testimony on the brake levers as “speculative.”

    Held

    The Court denied the Defendant Custom Equipment LLC’s motion to exclude the testimony of Plaintiff’s expert Craig Sylvester.

    Key Takeaway:

    The Court noted that while Defendant raised various other arguments for exclusion, none of these arguments provided a proper basis for exclusion, as they all speak to issues of fact-finding, not gatekeeping.

    For example, Defendant’s disagreement with Sylvester’s exclusion of other possible explanations for the accident and his reasons for doing so do not render his opinions inadmissible—they merely make it more likely that the trier of fact will view Sylvester’s conclusions about the root cause of the accident less credible. 

    Because the Court must act as “a gatekeeper, not a fact finder,” it cannot exclude portions of Sylvester’s testimony for any of these fact-finding based reasons.

    Case Details:

    Case Caption: Hartley V. Sunbelt Rentals, Inc
    Docket Number: 2:24cv1078
    Court Name: United States District Court, Washington Western
    Order Date: November 24, 2025
  • Licensing Expert’s Experience-Based Opinion Admitted 

    Licensing Expert’s Experience-Based Opinion Admitted 

    The fiery dispute in this case comes on the wings of a disagreement about dragon-themed boot buttons. In April 2021, Plaintiff, Edward Beard Jr. (“Beard”), filed a complaint against Defendants Arik Helman (“Helman”)1Link to the text of the note; Son of Sandlar, LLC; Son of Sandlar, Inc., Sandlar Manufacturing, LLC; and Twisted World, LLC (“Defendants”) for direct copyright infringement, contributory copyright infringement, vicarious infringement, and breach of contract.

    Defendants filed a motion to exclude the testimony of Dr. Wesley Austin while Plaintiff Edward P. Beard Jr. filed a motion to exclude the testimony of Cari Freno and Julie Newman.

    Economics Expert Witness

    Dr. Wesley Austin is an Associate Professor of Economics at University of Louisiana at Lafayette and has been in that position for eleven years.  He also has worked as an expert witness in various litigation since 2009.

    Austin holds a Bachelor of Arts in Finance and a Master of Arts in Economics—both from the University of South Florida. He received a Ph.D. in Economics from the University of South Florida, as well. His Ph.D. studies focused on health economics and public sector and labor economics and statistics.

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

    Art History Expert Witness

    Cari Freno is the chair of the art and art history department at Ursinus College. She has twenty-five years of experience “working with art materials and processes including drawing, carving, and casting” and has served as an art teacher since 2010.

    Freno has a Bachelor of Fine Arts from the University of the Arts and a Master of Fine Arts from Virginia Commonwealth University.

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

    Licensing Expert Witness

    Julie R. Newman is the Founder and CEO of Jewel Branding & Licensing, Inc. She has been a licensing agent for the past twenty-two years and represents artists whose artwork is used in manufacturers’ products. According to Newman, she “has developed licensing programs around the globe in categories such as health & beauty, stationery, apparel, gift, and home decor.” She holds a Bachelor of Arts in Finance from the University of Akron.

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

    Discussion by the Court

    Wesley Austin

    The purpose of Austin’s “report is to estimate [Beard’s] economic damages/losses” from the alleged copyright infringement.

    Challenges to Austin’s Qualifications

    While Defendants did not explicitly question the qualifications of Austin, their entire argument is premised on their belief that he “lacks experience or expertise in negotiating or structuring licensing deals, which is critical for providing a reliable opinion on reasonable royalties in the context of copyright infringement.”

    While Austin has an impressive background in economics, he has no experience, knowledge, or training relating to licensing agreements of the kind at issue in this case.

    So, while he may be qualified to testify regarding general economic matters, he lacked the requisite qualifications to be admitted as an expert on economic damages of the more specific area of art licensing agreements.

    Challenges to Austin’s Reliability

    Much of the Defendants’ challenge to Austin’s proposed expert testimony focused on his alleged unreliability. They noted that the focus of Austin’s analysis is improperly focused on what Plaintiff would have demanded, not what the parties would have negotiated.

    The Court agreed. Austin’s analysis is entirely focused on what Beard would have wanted, not what Helman would have offered.

    Be that as it may, the Defendants’ concerns are chiefly with Austin’s methodology and lack of an independent investigation. 

    The lack of investigation is shown by the fact that there is no evidence in the information provided to Austin that Beard ever received an advance against royalties (AAR) on a per year or per product basis, nor that an upcharge for color variants using his products was ever given. While Plaintiff is correct in noting that there is a basis for determining that an AAR is possible, Defendants contention is that the type of AAR which forms the basis of both of Austin’s scenarios (one granted for that high an amount on a per year, per product, and per color variant basis) has no basis in the record provided to Austin. That, specifically, is what the Court sees as having no evidence in the record to support a basis for an economic analysis and one of the things Austin should have conducted an independent investigation into.

    Relevance/Fit of Austin’s Analysis of Loss related to the Boot Buttons

    As a final note on Austin, the Defendants pointed out that he included lost future income for the Dragon Boot Buttons in his report.

    On March 06, 2024, the Court stated that “Helman is a joint author of the dragon buttons, and he cannot be sued for copyright infringement.”

    Since that opinion was released, more than one and half years have passed and Plaintiff has not amended its complaint to include a claim for accounting for profits from the boot buttons—a remedy that remains as viable as it was when it was mentioned in that opinion.

    Unless and until that motion and amended pleading are filed, Austin’s proposed analysis relating to the boot buttons is irrelevant to the claims currently within this case. 

    The Court viewed Austin’s potential testimony, and will view any testimony proffered on this topic, irrelevant until the amended complaint is filed.

    Cari Freno

    The purpose of Freno’s report is to “provide an opinion of the visual qualities appertaining to the items related to this case.”

    1. Challenges to Freno’s Qualifications

    Defendants’ chief issue with Freno’s report is that she “references no scholarly sources, industry standards, or error-rate analyses to validate her approach.” That is, their main concern is that her expertise is not scientific, and therefore not reliable.

    Freno has established that she has experience working within the art field and that is a sufficient basis for her expert opinion.

    Defendants did raise the valid point that while Freno has established an extensive background in the field of art, she provided no evidence that she has experience in the fields of leatherwork or metalwork. Further, she provided no mention that she has ever had experience turning a drawing or model into a physical product like an applique or a metal button. Nevertheless, this experience could be inferred from her previous work, and excluding the testimony of Freno based on her qualifications is not warranted.

    2. Challenges to Freno’s Lack of Investigation

    Freno’s report made it clear that she relied extensively on conversations with Helman. Freno provided no indication that she ever independently verified what Helman told her and she told the Court, explicitly, at the Daubert hearing that she did not conduct an investigation into what Helman told her.

    Freno’s visual analysis concluded by describing the differences between the various designs. It was only based on her extensive conversations with Helman that she ultimately concluded which design was based on the other.

    The obvious reliance on Helman’s opinions cannot be ignored by the Court—especially when it is admitted that nothing was done to verify the information. Ultimately, Freno’s lack of an independent investigation into what was told to her ultimately renders her testimony as an expert unreliable.

    Julie Newman

    Newman stated that the “primary purpose of [her] report is to summarize a licensing arrangement that would be typical for Helman and Beard to enter into.”

    Newman spent around half of her report arguing that many of the points made in the information given to Austin’s were “misleading and not based in real world licensing agreements.”

    Challenges to the Reliability of Newman’s Opinion

    Plaintiff’s chief concern with Newman’s report is its reliability. He first pointed to the fact that she did not rely on “any peer-reviewed or scientific model” and only relied on her extensive experience in the licensing field to come to her conclusions.

    The Court disagreed. Plaintiff seemed to want a peer reviewed paper or universally accepted formula to provide the basis for an expert report, but that was not required. Far from pulling figures out of thin air, she based her opinion on more than two decades of experience working to create licensing agreements like the one that could have been made in this case.

    She concisely explained in her report how and why she reached the conclusion that a 10% royalty rate was likely and that this would lead to royalties owed in the amount of $400.

    Challenges to the Fit of Newman’s Opinion

    According to the Plaintiff, because the “report fails to explain how her licensing experience anecdotes align with the specific market for this particular Dragon Design, or the specific infringement scenario before the Court – her report thus failed the “fit” test.”

    Despite Plaintiff’s implication that there is a lack of fit due to the lack of science used in the report, all that must be done for the fit element is for the trial judge to determine whether the testimony has “a reliable basis in the knowledge and experience of [the relevant] discipline.”

    Here, Newman’s report has more than a sufficient reliable basis for her opinions—she has worked within the relevant field on the exact documents at issue for over two decades. The fact it is an experience-based opinion rather than a scientific based one, did not affect the ability of the expert to provide her report or testimony in this case.

    Finally, when Newman stated that she has worked with artists as “a licensing agent” for twenty-two years, she also explicitly stated that she has worked on several art licensing agreements. She set forth these anecdotes almost immediately prior to laying out her conclusion and explained how her conclusion is based on her prior experiences.

    Held

    • The Court granted Defendants’ motion to exclude the opinions and testimony of Dr. Wesley Austin.
    • The Court granted in part and denied in part Beard’s motion to exclude the expert testimony of Cari Freno and Julie Newman- the motion to exclude was granted as to Cari Freno but denied as to Julie Newman.

    Key Takeaway:

    Experience is a valid basis to provide an expert opinion. The scientific factors simply are not applicable, when the reliability of testimony from a practical expert depends heavily on the knowledge and experience of the expert, rather than the methodology or theory behind it.

    When an expert relies solely or primarily on experience, they must explain 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.

    Case Details:

    Case Caption: Beard V. Helman
    Docket Number: United States District Court, Pennsylvania Middle
    Court Name: 4:21cv680
    Order Date: November 12, 2025
  • Physical Medicine And Rehabilitation Expert Was Allowed to Opine on Future Medical Expenses

    Physical Medicine And Rehabilitation Expert Was Allowed to Opine on Future Medical Expenses

    This case arises out of injuries sustained by Brandon Jensen on his bicycle when he collided with a semi-truck who made a left turn through his lane of travel. The semi-truck was driven by Defendant Michael Beale. Beale was working for Crete Carrier at the time of the accident.

    The Plaintiffs planned to introduce the testimony of Dr. Zachary L. McCormick, their medical expert, who will opine that Jensen’s future medical expenses will cost approximately $777,955.

    McCormick bases his estimates on the “historical cost of care available to me from the University of Utah.” The Defendants argued that the Court should exclude McCormick’s report. 

    Physical Medicine And Rehabilitation Expert Witness

    Dr. Zachary Lennon McCormick, MD is a board-certified specialist in both Pain Medicine and Physical Medicine & Rehabilitation (PM&R).

    He received his MD at the University of Pennsylvania, completed a PM&R residency and fellowship at Northwestern University (The Rehabilitation Institute of Chicago). Following training, he served as a faculty member at the University of California San Francisco. McCormick currently serves as a Professor and Vice Chair of PM&R, Ambulatory Chief Value Officer, Chief of the Division of Spine and Musculoskeletal Medicine, Co-Director of the Endoscopic and Percutaneous Spine (EPS) Destination Care Program, and the Founding Director of the Interventional Spine and Musculoskeletal Research (INSPIRE) program. He founded the Interventional Spine and Musculoskeletal Medicine (ISMM) Fellowship Program at the University of Utah and previously directed this program for 6 years.

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

    Discussion by the Court

    Just over a week ago, the Utah Supreme Court issued a decision holding that special damages for past medical expenses should be measured by the negotiated—not the gross—charge for services. The Defendants argued that the Court should exclude McCormick’s report for failure to comply with the Utah Supreme Court’s opinion.

    Although McCormick’s report focused on future, not past, medical expenses, the Defendants argued that the same logic applies and that any estimates for future services based on gross charges are inadmissible. The Defendants also maintained that McCormick’s report lacks foundation due to his failure to explain whether his estimates are based on gross charges or other rates.

    The Court held that the Plaintiffs may introduce the expert testimony of McCormick to the extent that his report presents evidence of gross charges for future medical expenses. But the Defendants may present evidence of the standard discount available to self-pay patients for those charges. In addition, the Defendants may raise questions about the foundation for McCormick’s testimony to the extent that his report is based on other measures of future medical expenses. 

    Held

    The Court declines to exclude the expert testimony of Dr. Zachary McCormick but clarified that the Defendants may introduce evidence concerning typical medical billing discounts for self-pay or uninsured individuals.

    Key Takeaway:

    The Court assumes that McCormick’s expert report is based on gross charges. The Court denied without prejudice the Defendants’ challenge to his report to the extent that their challenge is based on the lack of foundation about whether the figures represent gross charges or payer-negotiated charges. The Court will question McCormick about the source of his figures before determining the admissibility of his testimony.

    Case Details:

    Case Caption: Jensen V. Crete Carrier Corporation
    Docket Number: 1:23cv105
    Court Name: United States District Court for the District of Utah, Northern Division
    Order Date: November 10, 2025

    Please refer to the blog previously published about this case:

    Transportation Engineering Expert’s Testimony on Accident Reconstruction Admitted

    Transportation Expert’s Testimony About Safety Considerations Admitted

  • Psychiatry Expert Was Barred From Testifying About the Abuse Allegations 

    Psychiatry Expert Was Barred From Testifying About the Abuse Allegations 

    From 2020 to 2022, Plaintiff Jane Doe was dating Defendant Aaron Tanner, who at the time was a member of the Los Angeles County Sheriff’s Department (“LASD”) and the alleged leader of a law enforcement gang called the “Rattlesnakes.”

    According to Plaintiff, during the course of her relationship with Tanner, Tanner physically abused her. Tanner also warned Plaintiff that, “if she told anyone” about his abuse, the Rattlesnakes would “take care of her.”

    Plaintiff alleged that, after she broke up with Tanner in 2022, he and other members of the Rattlesnakes began to stalk and intimidate her. In 2023, the LASD’s Internal Affairs Bureau interviewed Plaintiff in connection with an “investigation into Tanner and a deputy who was stopped for a DUI by Tanner.” Later that year, the LASD’s Internal Criminal Investigations Bureau formally opened an investigation on Tanner. Soon after, law enforcement officers began to surveil Plaintiff’s home and, in one instance, “the gas tank of her car was tampered with, in an apparent effort to cause her to crash her car.” The LASD has since terminated Tanner’s employment, but Plaintiff alleges Tanner continues to stalk her, and she fears further retaliation from the Rattlesnakes.

    The County filed motions to exclude the testimony of Dr. George Elias and Mr. Roger Clark, who Plaintiff has named as a psychiatric expert and as a police practices expert, respectively.

    Psychiatry Expert Witness

    Dr. George R. Elias is certified by the American Board of Psychiatry and Neurology in both Adult and Forensic Psychiatry. He is licensed to practice medicine in the states of California and Missouri.

    He is also licensed as an Out-of-State Telehealth Provider in Florida. Elias has provided expert opinion on various criminal and civil matters through written reports, testimony, and deposition. Elias is currently the President of Elias Diagnostix, a private forensic and outpatient psychiatric practice.

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

    Law Enforcement Expert Witness

    Roger Clark has worked as a Deputy Sheriff, Sergeant, and Lieutenant in the LASD over the span of a 27-year career.

    Clark frequently spoke out about law enforcement gangs, drafted an internal memorandum addressing the topic, and spoke with various LASD executives to voice his concerns. 

    Since retiring from the LASD in 1994, Clark has worked as a police practices consultant and has been retained in over 2,600 cases.

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

    Discussion by the Court

    A. Discovery Sanctions

    The County argued that Elias and Clark should not be permitted to testify because the Plaintiff failed to disclose either expert by the July 30, 2025, deadline set out in the Court’s December 26, 2024, Scheduling Order.

    Instead, Plaintiff disclosed Elias as an expert on August 4, 2025, and served his expert report on August 13, 2025—the deadline for either party to designate rebuttal experts. Plaintiff also identified Clark as an expert on August 4, 2025, serving Clark’s initial report the same day and a revised copy of his report on August 8, 2025.

    Here, Plaintiff disclosed both Elias and Clark as experts five days after the deadline set out in the Court’s Scheduling Order, served Clark’s report the same day, and served Elias’ report approximately nine days later, all before the close of expert discovery and more than a month before the deadline to file a motion for summary judgment.

    True, Plaintiff’s delay prevented the County from naming a rebuttal witness to Elias by the deadline set out in the Court’s Scheduling Order. However, even though expert discovery is now closed, Plaintiff has offered to enter into a stipulation that would allow the County to designate a rebuttal expert. Moreover, notwithstanding Plaintiff’s delay, Defendant designated a rebuttal expert to respond to Clark’s opinions and deposed both Elias and Clark.

    Given the minimal harm from Plaintiff’s untimely disclosure, Defendant’s opportunity to cure that harm through measures short of exclusion, the lack of any substantial impact on the trial schedule, and the absence of any indication Plaintiff acted willfully or in bad faith, the Court found Plaintiff’s untimely disclosure harmless and declined to exclude either Elias or Clark on that basis.

    B. George Elias

    Plaintiff offered Elias as an expert on “Plaintiff’s psychological condition, stress, and emotional and mental damages.”

    Elias offered proposed testimony that (1) Plaintiff “meets DSM-5 Diagnostic Criteria for Post-Traumatic Stress Disorder [(“PSTD”)], with dissociative symptoms”; (2) Plaintiff “suffered from severe emotional distress that was a result of [Tanner’s] conduct”; and (3) Plaintiff’s “Post-Traumatic Stress Disorder is attributable to the severe emotional distress she endured.”

    Analysis

    The Court disagreed that Elias’ opinions are unsupported by a reliable methodology. Elias conducted a four-hour interview of Plaintiff, during which he “obtained a longitudinal history of Plaintiff, which included the onset, course, and severity of [her] symptoms, along with any associated clinically significant dysfunction.”

    Before diagnosing Plaintiff with PTSD, Elias “considered her medical history,” “reviewed her psychotherapy records,” and “performed a differential diagnosis.” Before reaching his diagnosis, Elias screened out “bipolar spectrum disorder, a prior history of depression, and substance use issues” as possible causes of Plaintiff’s symptoms. Finally, Elias reached a diagnosis based on the diagnostic criteria set out in the DSM-5. 

    The County argued that this is not enough, because Elias “did not obtain collateral information from family members, co-workers, or treating providers” and “did not administer any standardized tests commonly used in psychiatric evaluations, such as the CAPS-5, PCL-5, or MMPI-2.”

    However, these criticisms go to the weight of Elias’ testimony, not its admissibility.

    Nevertheless, the Court agreed that Elias may not testify that Tanner’s conduct “caused” Plaintiff’s PTSD. As an expert witness, Elias has no personal knowledge of Tanner’s conduct and cannot testify as to the credibility of Plaintiff’s specific allegations of abuse.

    C. Roger Clark

    Clark offered seven opinions: (1) Tanner used “excessive force” by “choking out” Plaintiff; (2) the “Rattlesnakes are a subgroup in LASD operating out of the Lancaster Station”; (3) the “Rattlesnakes meet the definition of a deputy gang,” as determined by Clark; (4) “Tanner’s references to the [R]attlesnakes in conversation with [Plaintiff] would intimidate a witness”; (5) Clark has not seen any evidence that would justify Tanner’s use of force under Peace Officer Standards and Training (“POST”) or LASD policies; (6) the LASD tolerates deputies’ use of excessive force, fails to properly investigate excessive force complaints, and fails to properly investigate and discipline membership in law enforcement gangs; and (7) the “collective approvals by the LASD puts the general public at unnecessary future risk of death and/or injury from the Defendant Deputies” and others in the LASD.

    Analysis

    The County argued that Clark is not qualified to testify on law enforcement gangs, six of his seven opinions amount to improper legal conclusions, his fourth opinion is not supported by a reliable methodology, and his seventh opinion is subject to exclusion under Rule 403.

    As a preliminary matter, Clark is adequately qualified to testify as to law enforcement gangs within the LASD.

    However, the Court agreed that four of Clark’s seven proposed opinions are improper. To start, Clark may not testify that “Deputy Tanner’s references to the Rattlesnakes in conversations with Plaintiff would intimidate a witness.” Nothing in Clark’s experience qualifies him to testify as to what “would intimidate a witness” and, to the extent Clark proposed to testify as to whether Tanner in fact intimidated Plaintiff, his proposed testimony improperly speculated as to Plaintiff’s state of mind.

    Likewise, Clark may not testify that the “collective approvals by the LASD put the general public at unnecessary future risk of death and/or injury from the Defendant Deputies and others in the department,” because this proposed testimony would not be helpful to the jury and added nothing beyond the sixth opinion set out in his report.

    Next, Clark’s opinions addressing the use of “excessive” and “unreasonable” force amounted to legal conclusions. To the extent such testimony is relevant, Clark may only testify as to whether Tanner’s use of force conformed to POST standards and LASD policies.

    The Court rejected the County’s argument that Clark’s remaining opinions are legal conclusions. Indeed, the County has not sufficiently explained how any of the terms Clark used in those opinions “have a specialized meaning in law” or how Clark has “attempted to instruct the jury on the law” or to “apply the law to the facts of the case.”

    Held

    The Court granted in part and denied in part the Defendant County of Los Angeles’s motions To exclude Dr. George Elias and Roger Clark.

    Key Takeaway:

    While Elias did not obtain collateral information from family members, co-workers, or treating providers, Elias is an experienced medical professional, the DSM is a recognized source of authority within the psychiatric community, and the County did not argue that Elias has misapplied the DSM.

    Case Details:

    Case Caption: Jane Doe V. County Of Los Angeles
    Docket Number: 2:24cv8649
    Court Name: United States District Court, California Central
    Order Date: October 28, 2025
  • Law Enforcement Expert Allowed to Opine on the Reactionary Gap 

    Law Enforcement Expert Allowed to Opine on the Reactionary Gap 

    This suit involves the unnecessary use of excessive force by police officers against a black man suffering from a mental health crisis.

    On November 21, 2021, during a mental health crisis, Jabari Asante-Chioke encountered Louisiana State Police (“LSP”) Officer Nicholas Dowdle and East Jefferson Levee District (“EJLD”) Officers Jonathon Downing and Gerard Duplessis (collectively referred to herein as “Officer Defendants”

    Plaintiff, Malikah Asante-Chioke, individually, and on behalf of her father, Jabari Asante-Chioke, herein filed this action against the Defendants, accusing them of failure to use less-than-lethal methods in accordance with training and state and federal law, to subdue Mr. Asante-Chioke.

    Malikah Asante-Chioke filed a motion to exclude the testimony of John J. Ryan.

    Law Enforcement Expert Witness

    John J. Ryan has been actively involved in police practices and law enforcement since 1981.

    He was an active police officer for twenty years in Providence, Rhode Island. In the final year of his active career and since his retirement in June of 2002 from police services, he has been involved in police and law enforcement practices as a private consultant regarding law enforcement issues.

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

    Discussion by the Court

    I. Legal Conclusions

    Plaintiff sought to exclude Ryan’s statement in his report which provides, “It is well known that [if] [sic] an officer reasonably perceives an immediate threat of serious bodily harm or death against themselves, another officer, or any third party, the officer may respond with deadly force.”

    EJLD Defendants argued that a full reading of Ryan’s opinion will explain how this statement is based on Ryan’s “expertise in generally accepted [police] policies, practices, training, and industry standards.”

    While that may be the case, the Court held that Ryan’s statement is not couched in the appropriate terms.

    The Court will not exclude Ryan’s statements of applicable police standards and practices, nor his conclusion that Officers Downing and Duplessis complied with those standards. As the Court has explained, an expert may opine on whether officers complied with applicable police policies and procedures.

    EJLD Defendants argued that Ryan did not need to discuss relevant East Jefferson Levee District policies and procedures and the Court agreed.

    Lastly, Plaintiff argued that Ryan offered impermissible legal opinions because he opined that the EJLD Defendants acted reasonably. While reasonableness is an inadmissible legal conclusion, Plaintiff failed to offer specific examples from Ryan’s report where he opined on the reasonableness of the EJLD Defendants’ actions.

    II. The “Reactionary Gap”

    Plaintiff also argued that Ryan is unqualified to opine on the “reactionary gap” between when an officer receives a stimulus to stop or start firing and when an officer responds to said stimulus.

    EJLD Defendants argued that Ryan is qualified to opine on reaction time because he has spent numerous hours training officers in shooting scenarios, including conducting stimulus drills on a shooting range. The Court agreed with EJLD Defendants.

    Plaintiff also argued that, even if Ryan were qualified, his opinions on the reactionary gap will not help the factfinder because perception reaction times are common sense. However, the Court disagreed. In this case, Ryan may help the factfinder determine whether the Defendants officers’ actions to continue shooting Asante-Chioke were reasonable. Consequently, the Court refused to exclude Ryan’s testimony as unhelpful.

    III. Ryan’s Factual Interpretations

    Plaintiff also argued that the Court should exclude “Ryan’s opinions that merely recite defense counsel’s factual and legal narratives.”

    EJLD Defendants argued that Ryan’s opinions are not based on defense counsel’s factual and legal narratives, but instead are based on his view of the body cam, dash cam, and bystander video evidence. This Court agreed with EJLD Defendants. Throughout his report, Ryan utilized the available video evidence and deposition testimony to formulate his opinions. 

    Held

    The Court granted in part and denied in part Malikah Asante-Chioke’s motion to exclude the testimony of John J. Ryan.

    Key Takeaway:

    While a lay person may have a general understanding of perception reaction times, “a lay person typically would not have experience or knowledge about the time it takes an officer to react to a perceived threat or the absence of a perceived threat.”

    By opining that shooting officers take time to react to a stimulus to stop shooting, Ryan may help the factfinder determine whether the Defendants officers’ actions to continue shooting Asante-Chioke were reasonable.

    Please refer to the blog previously published about this case:

    Biomechanics Expert Was Allowed to Opine on the Source of Bullet Wounds

    Case Details:

    Case Caption: Asante-Chioke V. Dowdle Et Al
    Docket Number: 2:22cv4587
    Court Name: United States District Court, Louisiana Eastern
    Order Date: November 21, 2025