United States v. Grenkoski: Overdose-Death Evidence in Pill-Mill Cases Requires a Defendant Nexus and Can Prove Subjective Knowledge

I. Introduction

In United States v. Mark Grenkoski (joint appeal with co-defendants Evann Herrell and Keri McFarlane), the Sixth Circuit reviewed wide-ranging challenges to convictions arising from the operation of “Express Health Care” (EHC), a purported addiction-treatment clinic the jury found to be a cash-driven “pill mill.” After a 30-day trial, all three doctors were convicted on multiple conspiracy counts, including conspiracy to distribute controlled substances, health care fraud, and money laundering.

The appeal presented recurring post-United States v. Ruan issues about physician mens rea under the Controlled Substances Act, as well as substantial evidentiary disputes typical of pill-mill prosecutions (patient diversion evidence, clinic culture evidence, regulatory backdrop, and references to patient deaths). The court largely affirmed, finding most claims meritless and any errors harmless.

II. Summary of the Opinion

The Sixth Circuit affirmed the convictions and sentences. Key holdings include:

  • Sufficiency: The evidence supported the jury’s findings that the defendants knowingly participated in a conspiracy to prescribe controlled substances in an unauthorized manner, consistent with United States v. Ruan’s subjective-knowledge requirement, and that sufficient evidence supported Grenkoski’s health care fraud conspiracy conviction.
  • Evidentiary rulings: The court upheld most Rule 403 and hearsay rulings, including exclusion of evidence that the federal “X-waiver” patient caps were repealed years after the conspiracy, and admission of diversion-related statements to show effect on listeners and notice to doctors.
  • New/clarified precedent (publication): The court endorsed admitting evidence of patient overdose deaths only when the government demonstrates “connectivity” (a nexus) to the defendants, and it expressly approved the reasoning that continued prescribing after learning of an overdose death can show “wanton disregard” and knowledge of misuse.
  • Jury instructions: Instructions tracked Ruan and Sixth Circuit precedent; the deliberate-ignorance instruction was upheld.
  • Sentencing procedure: Under Rule 35(a), the district court lacked jurisdiction to correct a sentence after 14 days, even if the motion was filed on day 14, consistent with United States v. Hall.

III. Analysis

A. Precedents Cited

1. Post-Ruan mens rea and pill-mill sufficiency cases

  • United States v. Ruan, 597 U.S. 450 (2022): The centerpiece. The panel applied Ruan for the rule that the government must prove a doctor “subjectively knew” prescriptions were unauthorized (not merely that conduct departed from objective standards of care).
  • United States v. Bauer, 82 F.4th 522 (6th Cir. 2023): Used to confirm subjective knowledge may be proven circumstantially (e.g., red flags, diversion indicators), and to uphold the deliberate-ignorance instruction as compatible with Ruan.
  • United States v. Anderson, 67 F.4th 755 (6th Cir. 2023) (per curiam): Cited for reliance on expert testimony contrasting legitimate practice against pill-mill patterns; also used in discussing health care fraud and “medical necessity.”
  • United States v. Elliott, 876 F.3d 855 (6th Cir. 2017): Pre-Ruan but still relevant factually for pill-mill indicia (abnormal doses, minimal exams, range of violations).
  • United States v. Stanton, 103 F.4th 1204 (6th Cir. 2024): Important for conspiracy framing—conviction does not require completion of the predicate offense by the defendant, and deliberate avoidance of learning illicit practices may support conspiracy liability.
  • United States v. Suetholz, No. 23-5613, 2024 WL 4182903 (6th Cir. Sep. 13, 2024): Though unpublished, it became pivotal in the court’s discussion of overdose-death evidence; the panel “affirm[ed] that reasoning today,” elevating the concept into a published endorsement.

2. Health care fraud—omissions and materiality

  • United States v. Bertram, 900 F.3d 743 (6th Cir. 2018): Supplies the doctrinal bridge that health care fraud may be committed via material omissions to Medicare, supporting the duplicative-testing theory.
  • Scott v. First S. Nat'l Bank, 936 F.3d 509 (6th Cir. 2019): Used for forfeiture—arguments not raised in an opening brief are forfeited.

3. Evidence law and trial administration

  • United States v. Wilder, 87 F.4th 816 (6th Cir. 2023) and United States v. Potter, 927 F.3d 446 (6th Cir. 2019): Provide the “low bar” for Rule 401 relevance.
  • United States v. Campbell, 135 F.4th 376 (6th Cir. 2025): Used to justify exclusion of temporally mismatched regulatory or guideline changes—“timeline mismatch” reduces probative value and increases juror confusion under Rule 403.
  • United States v. Blackwell, 459 F.3d 739 (6th Cir. 2006): Right-to-present-a-defense is not violated by correct application of standard evidentiary rules unless excluded evidence would create reasonable doubt.
  • United States v. Kerley, 784 F.3d 327 (6th Cir. 2015) (quoting United States v. Cuti, 720 F.3d 453 (2d Cir. 2013)): Supports allowing lay testimony about how a witness would have acted with different information as within Rule 701.
  • United States v. Churn, 800 F.3d 768 (6th Cir. 2015) and Gover v. Perry, 698 F.3d 295 (6th Cir. 2012): Central hearsay framework—out-of-court statements offered for effect on the listener or to explain conduct are not hearsay if relevant.
  • United States v. Clay, 667 F.3d 689 (6th Cir. 2012) (quoting United States v. Sanders, 95 F.3d 449 (6th Cir. 1996)): Rule 403 unfair prejudice requires more than “paint[ing] the defendant in a bad light.”
  • United States v. Betro, 115 F.4th 429 (6th Cir. 2024) and United States v. Wells, 211 F.3d 988 (6th Cir. 2000): Define the boundary between lay and expert testimony by physicians.

4. Severance and cumulative error

  • United States v. Medlock, 792 F.3d 700 (6th Cir. 2015), United States v. Ledbetter, 929 F.3d 338 (6th Cir. 2019), and United States v. Tocco, 200 F.3d 401 (6th Cir. 2000): Reinforce strong preference for joint trials and requirement of “compelling, specific, and actual prejudice.”
  • United States v. Warman, 578 F.3d 320 (6th Cir. 2009) and United States v. Underwood, 859 F.3d 386 (6th Cir. 2017): Cumulative error requires combined harmless errors to render the trial fundamentally unfair—high bar not met.

5. Rule 35 jurisdictional limit

  • United States v. Hall, 661 F.3d 320 (6th Cir. 2011): Controls the court’s conclusion that the district court lacks jurisdiction to correct a sentence if it does not act within 14 days, even where a motion is timely filed.

B. Legal Reasoning

1. Controlled-substance conspiracy after Ruan: subjective knowledge proven by pill-mill “telltale signs”

The panel treated Ruan as setting a subjective mens rea requirement—doctors must knowingly or intentionally prescribe in an unauthorized manner. Rather than requiring direct admissions, the court emphasized circumstantial proof: ultra-brief visits, “three three three” dosing, ignoring negative tests, prescribing despite intoxication, signing prescriptions for unseen patients, falsified documentation, and financial incentives tied to patient volume. Consistent with United States v. Bauer and United States v. Elliott, the court considered these factors sufficient for a rational jury to find knowledge.

The conspiracy posture mattered. Citing United States v. Stanton, the court underscored that the verdict need not turn on whether any one defendant completed a substantive § 841 offense, and that “deliberate avoidance” of learning a clinic’s illicit practices can sustain conspiracy culpability. This framing reduces the effectiveness of defenses premised on compartmentalization (“I didn’t personally see X patient”) where the operational model and repeated red flags were pervasive.

2. Health care fraud: unnecessary testing plus Medicare omissions

On health care fraud, the court credited evidence that EHC ordered duplicative presumptive and confirmatory urine tests with “no need” and “no benefit,” supporting the inference that the clinic obtained reimbursement by omitting material facts Medicare required. Relying on United States v. Bertram, the panel reiterated that omissions can constitute fraud when they secure payment that would not have been made had the truth been disclosed. It also enforced appellate forfeiture under Scott v. First S. Nat'l Bank as to an unbriefed “standing order” theory.

3. Rule 403 and the “regulatory story”: excluding post-conspiracy repeal of the X-waiver caps

The defense sought to introduce that the DEA repealed buprenorphine patient caps (the “X-waiver rule”) in 2023, years after the conspiracy ended in 2018. The court assumed arguendo relevance under Rule 401 but upheld exclusion under Rule 403 because the repeal risked jury confusion and had scant probative value about defendants’ intent during the charged period. By invoking United States v. Campbell’s “timeline mismatch” rationale, the court signaled a general approach: later regulatory relaxation is weak evidence of earlier legality or good faith, particularly when the government’s theory is that defendants attempted to circumvent the then-existing rules.

4. Hearsay disputes: effect on listener, clinic culture, and notice to prescribers

The court treated statements about diversion and clinic impropriety as admissible non-hearsay when offered to show their effect on witnesses (e.g., why an employee quit), or to demonstrate notice to clinicians about possible diversion. Citing United States v. Churn and Gover v. Perry, the panel effectively approved a common prosecution method in pill-mill cases: using patient and staff statements not primarily to prove the underlying misconduct (e.g., “the patient really diverted”), but to show the environment and the information flowing to prescribers—information from which subjective knowledge can be inferred.

5. Lay opinion boundaries: speculative “would you have” questioning

Relying on United States v. Kerley (and United States v. Cuti), the court upheld a co-conspirator physician’s testimony that he would not have written illegal prescriptions but for EHC. The court viewed this as permissible Rule 701 testimony about how the witness would have acted, and also as largely cumulative of the witness’s prior non-hypothetical testimony.

6. New/clarified published rule: overdose-death evidence is admissible with a defendant nexus and can prove subjective knowledge

The opinion’s most explicitly precedential evidentiary discussion concerns references to patient deaths. The district court permitted such evidence only if the government showed “connectivity” between the deaths and the defendants; the panel agreed that this limiting principle was sound and consistent with other courts. Crucially, the Sixth Circuit endorsed (and “affirm[ed]…today”) the reasoning that a doctor’s failure to adjust dangerous prescribing practices after learning of a patient’s overdose death can demonstrate “wanton disregard” and knowledge that patients were misusing prescriptions (drawing from United States v. Suetholz, which in turn quoted United States v. Schwartz and United States v. Bourlier).

Although the court found error where two deaths were mentioned without the required nexus and without a limiting instruction, it held the error harmless due to cumulative evidence and strong proof overall. Even so, the published endorsement of the “connectivity + knowledge inference” framework is likely to guide district courts on the admissibility and structuring (including limiting instructions) of death evidence in controlled-substance prosecutions.

7. Jury instructions: Ruan-compliant knowledge and Sixth Circuit deliberate-ignorance language

The court upheld instructions requiring proof beyond a reasonable doubt that defendants knew prescriptions were not issued for a legitimate medical purpose in the usual course of practice, finding the language tracked Ruan “nearly verbatim.” It also rejected objections to the deliberate-ignorance instruction, noting it is an evidentiary pathway for proving knowledge and reaffirming prior approvals of materially identical instructions in United States v. Bauer, United States v. Stanton, United States v. Anderson, and United States v. Campbell.

8. Rule 35(a): jurisdiction depends on the court acting within 14 days

Finally, applying United States v. Hall, the court held that Rule 35(a)’s 14-day window is jurisdictional as to the district court’s authority to correct a sentence: filing on day 14 does not preserve jurisdiction if the court rules after the 14 days lapse. This provides a stark procedural lesson for post-sentencing practice in the circuit.

C. Impact

  • Overdose-death evidence (key practical change): Trial courts in the Sixth Circuit now have a published roadmap: such evidence is potentially admissible, but only with a demonstrated nexus to the defendant and typically for the purpose of showing knowledge/wanton disregard (e.g., continued prescribing after learning of the death). Expect more litigation over what counts as sufficient “connectivity” (direct patient relationship, chart notes, internal reports, staff warnings, etc.) and heightened attention to limiting instructions.
  • Defense limits on “regulatory repeal” narratives: The decision strengthens the government’s ability to exclude later regulatory relaxations (like the X-waiver repeal) as confusing and minimally probative, especially where the charged conduct involves circumvention of contemporaneous rules.
  • Conspiracy proof in pill-mill settings: By emphasizing Stanton and the permissibility of proving knowledge via deliberate avoidance and pervasive red flags, the opinion reinforces that physicians cannot rely on formalities (paper policies, nominal addiction-clinic labels, or isolated compliant acts) when the overall operation points to illegitimate practice.
  • Health care fraud via “medically unnecessary” testing theories: The court’s discussion aligns controlled-substance cases with parallel testing-fraud theories, making it easier for the government to frame standing orders/duplicative testing as fraud when Medicare requires individualized justification.
  • Rule 35 practice: The reaffirmed jurisdictional reading will pressure counsel to pursue alternative mechanisms (appeal, § 2255, or timely Rule 35 where applicable) and to understand that a timely filing does not ensure the district court can act.

IV. Complex Concepts Simplified

  • “Unauthorized” prescriptions: A controlled-substance prescription is lawful only if issued for a legitimate medical purpose in the usual course of professional practice. Post-Ruan, the government must prove the doctor actually knew the prescriptions were unauthorized.
  • Conspiracy vs. the underlying offense: Conspiracy punishes agreement to commit a crime. The government need not prove each conspirator personally completed every substantive act, only that they knowingly joined the agreement and intended to further it.
  • Deliberate ignorance (willful blindness): Jurors may infer knowledge when a defendant suspects a high probability of illegality and deliberately avoids confirming it. It is not mere negligence; it is purposeful avoidance.
  • Rule 403 unfair prejudice: Evidence can be excluded if its risk of inflaming or confusing the jury substantially outweighs its probative value. The fact that evidence is damaging does not make it “unfairly” prejudicial.
  • Hearsay vs. “effect on the listener”: An out-of-court statement is hearsay only when offered to prove it is true. If offered to show its impact on someone’s actions (e.g., the statement prompted an employee to quit or prompted a report to a doctor), it is generally not hearsay.
  • Rule 35(a) 14-day limit: In this circuit, the district court must correct the sentence within 14 days of oral announcement; otherwise it lacks jurisdiction, even if the defendant filed a motion within that window.

V. Conclusion

The Sixth Circuit’s decision in United States v. Grenkoski is a comprehensive reaffirmation of how federal courts evaluate pill-mill evidence after United States v. Ruan: subjective knowledge can be proven through pervasive red flags, clinic practices, notice of diversion, and deliberate avoidance. Most notably, the court endorsed—now in a published opinion—the principle that patient overdose-death evidence may be admissible when tied to a defendant and can support an inference of knowledge/wanton disregard when prescribing continues after such notice. Coupled with its approval of excluding post-conspiracy regulatory repeals under Rule 403 and its strict application of Rule 35’s jurisdictional window, the opinion will influence both charging and trial strategy in controlled-substance and related fraud prosecutions across the Sixth Circuit.