Compliance Expert’s Testimony on the Hallmarks of a Pill Mill Excluded
Posted on October 17, 2025 by Expert Witness Profiler
Defendant Heather Marks, a nurse practitioner, is charged in a Superseding Indictment with distributing and conspiring (with her former co-defendant, Hemal Mehta, M.D.) to distribute Schedule II controlled substances outside the usual course of professional practice and without a legitimate medical purpose.
The Defendant also sought to introduce the testimony of Michael W. Staples, CMBI, as a “Regulatory and Legal Health Care Compliance Expert.”
Marks has submitted an expert report by Staples, showing that he proposes to testify about (1) the challenges of “Rural Healthcare”; (2) the characteristics of a “Pill Mill” and “bad faith-controlled substance prescribing”; and (3) patient stigma related to controlled substance prescribing and addressing aberrant issues.
The government argued that Staples is not qualified to testify as an expert to offer the evidence he proposes to offer and that his proposed testimony is both unreliable and irrelevant.

Compliance Expert Witness
Michael W. Staples has twenty-five years’ of experience in criminal investigations, regulatory and criminal healthcare investigations, medical standards of care investigations, scope of medical practice investigations, and healthcare regulatory and legal compliance.
Discussion by the Court
A. “The Challenges of ‘Rural Healthcare'”
Regarding his first proposed topic, the government argued that Staples is not a medical practitioner of any kind and therefore is not qualified to offer medical opinions, using medical jargon, about the appropriate standard of medical care in any setting. More specifically, the government asserted that Staples is not qualified to opine that the applicable standard of care that applies to medical practitioners in the rural setting is different from that governing medical practitioners in urban settings.
The Court agreed that Staples cannot offer medical testimony or testify about the medical standard of care per se. Consequently, he cannot offer an opinion that the practice of medicine in a rural setting changes the applicable standard of care—this is a medical issue. Nor may he opine that the rural setting somehow altered the legal requirements for proving a violation. However, insofar as Marks’ defense in this case is that she subjectively believed that she was authorized to issue the prescriptions at issue, because she did so in the usual course of her professional practice and with a legitimate medical purpose, Staples’ testimony about the unique challenges facing medical practitioners in rural areas appeared to have some bearing on whether her belief was objectively reasonable.
The Court held that while Staples may not offer a medical opinion, his experience and training as a healthcare regulatory consultant, investigator, and expert provided him a sufficient basis to proffer an opinion that the rural setting of Marks’ practice posed significant challenges for providers not found in urban settings.
B. “Characteristics of a ‘Pill Mill’ and ‘Bad Faith controlled substance prescribing'”
The Defendants argued that they “should not be foreclosed from asking agents about the hallmarks of a ‘pill mill’ case or the wide swath of conduct that is captured by this particular charging statute.”
The Court addressed this issue orally at a pretrial conference on August 25, 2021, stating that, insofar as the Defendants wanted to question law enforcement agents about the “hallmarks of a pill mill case,” such testimony “would not be allowed,” as it “gets into the charging decision by the government, which is really no concern of the jury.”
Staples sought to testify both about the hallmarks of a pill mill and that Marks’ practice did not demonstrate any of the characteristics of a pill mill. The government argued that the first part of the proposed testimony is barred by the Court’s previous ruling, that the second part constituted medical opinion testimony, and that both are irrelevant because the government never intended to argue that Marks’ medical practice was a pill mill.
The Court held that Staples will not be permitted to argue about the hallmarks or characteristics of a pill mill or that Marks’ practice did not carry any of these hallmarks.
C. Patient “Stigma”
Marks did not address the issue of “patient stigma” in responding to the government’s motion to exclude. The Court found that this part of Staples’ opinion did not offer an opinion tied to or related to any evidence or issue in this case, appeared to constitute medical opinion, and is simply not relevant.
D. Urine Drug Testing
Regarding Staples’ opinions about the use of urine drug testing as a “tool” to be utilized by medical practitioners but not the “sole basis for diagnosis and treatment decisions” and his long list of factors that may cause a negative drug urine test, the Court found that this testimony steps over the line between lay and medical opinion and is not admissible through Staples. In any event, Marks did not address the government’s argument regarding this portion of Staples’ Report or even attempt to justify its introduction.
Held
The Court granted in part and denied in part the government’s motion to exclude the testimony of Michael Staples.
Key Takeaway:
Staples’ proposed testimony about the unique challenges posed by the rural setting in which Marks’ practice was situated may be relevant to the objective reasonableness of her prescribing practices. As a result, Staples was allowed to offer limited expert testimony on the “unique circumstances that physicians in rural areas face and how this adversely affects their practice.”
Case Details:
Case Caption: | United States V. Marks |
Docket Number: | 2:19cr3 |
Court Name: | United States District Court, Tennessee Middle |
Order Date: | September 30, 2025 |