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United States v. Kahn

2026-08-20

Summary

Holding. The court affirmed Kahn's convictions on all counts challenged on appeal, finding that expert testimony regarding prescribing standards was properly admitted, sufficient evidence supported both his continuing criminal enterprise conviction and his drug-distribution conviction in connection with Jessica Burch's death, and DEA registration does not shield physicians from criminal liability when they prescribe outside the usual course of professional practice.

Shakeel Kahn, a licensed physician, operated pain clinics in Arizona and Wyoming where he sold prescriptions for oxycodone and other controlled substances using a standardized business model. Patients paid flat fees for 30-day supplies of extremely high doses—far exceeding medical guidelines—often without proper medical exams. Kahn's wife, brother, and employees assisted in the operation; additional individuals brought new patients to the clinics and facilitated sales in exchange for portions of the medication. One patient, Jessica Burch, died after overdosing on oxycodone that Kahn prescribed to her.

After an initial conviction was vacated by the Supreme Court due to a jury instruction error regarding the mens rea requirement in the controlled substances statute, Kahn was retried and convicted on seventeen of twenty-one charges. On appeal, Kahn challenged the admission of expert testimony about prescribing authority, the sufficiency of evidence for his continuing criminal enterprise and drug-distribution-resulting-in-death convictions, and argued that DEA-registered prescribers cannot face criminal liability. The court rejected all challenges and upheld the convictions.

Summary generated by law.co from the public-domain opinion. The opinion text itself is public domain.

Key issues

  • Admissibility of expert testimony regarding the scope of prescribing authority and medical standards
  • Sufficiency of evidence for continuing criminal enterprise conviction based on management over five or more co-conspirators
  • Sufficiency of evidence that defendant's prescribed oxycodone caused victim's death
  • Criminal liability of DEA-registered physicians for prescriptions outside the usual course of professional practice

Procedural posture

This is an appeal from a district court conviction following a retrial ordered by the appellate court after the Supreme Court vacated the original convictions for jury instruction error.

Authorities cited

Opinion

majority opinion

Appellate Case: 25-8004 Document: 89-1 Date Filed: 08/20/2026 Page: 1

FILED

United States Court of Appeals

Tenth Circuit

PUBLISH

August 20, 2026

UNITED STATES COURT OF APPEALS

Christopher M. Wolpert

FOR THE TENTH CIRCUIT Clerk of Court

UNITED STATES OF AMERICA,

Plaintiff - Appellee,

v. No. 25-8004

SHAKEEL A. KAHN,

Defendant - Appellant.

Appeal from the United States District Court

for the District of Wyoming

(D.C. No. 2:17-CR-00029-ABJ-1)

Beau B. Brindley, Chicago, Illinois, for Defendant-Appellant.

Z. Seth Griswold, Assistant United States Attorney (Darin D. Smith, United States Attorney, Stephanie I. Sprecher, Assistant United States Attorney, with them on the brief), Casper, Wyoming, for Plaintiff-Appellee.

Before HOLMES, Chief Judge, MATHESON, and FEDERICO, Circuit

Judges.

FEDERICO, Circuit Judge.

Shakeel A. Kahn, with the help of his wife, brother, employees, and

patients, sold prescriptions for oxycodone and other drugs to the patrons of

Appellate Case: 25-8004 Document: 89-1 Date Filed: 08/20/2026 Page: 2

his pain clinics in Wyoming and Arizona. One woman, Jessica Burch, died

after overdosing on the oxycodone that he prescribed to her.

Kahn was charged with multiple crimes, including several counts of

unlawful dispensing of a controlled substance via an unauthorized

prescription and one count of leading a continuing criminal enterprise.

Kahn was previously convicted of several charges after his first jury trial,

which this court affirmed. The Supreme Court granted Kahn’s subsequent

petition for certiorari and ultimately vacated his convictions for legal error

in a jury instruction. On remand, Kahn was tried for a second time and was

convicted on seventeen of the twenty-one charges. He now appeals his

convictions.

On appeal, Kahn challenges: (1) the admission of expert testimony

into evidence regarding the law governing prescriptions; (2) the sufficiency

of the evidence to support his convictions for leading a continuing criminal

enterprise and for unlawfully dispensing a controlled substance resulting

in the death of Jessica Burch; and (3) the use of a regulation to guide

whether Kahn’s prescriptions were authorized and lawful. We have

jurisdiction under 28 U.S.C. § 1291 and affirm.

I

“Because this appeal is before this court following a jury verdict, we

state the facts in the light most favorable to the jury’s decision.” Little v.

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Budd Co., Inc., 955 F.3d 816, 818 (10th Cir. 2020). Shakeel A. Kahn, a

licensed medical doctor, operated pain clinics in Arizona and Wyoming. His

brother Nabeel Khan managed the Arizona clinic, and his wife Lyn Kahn

managed the Wyoming clinic. Kahn opened the Wyoming clinic after some

pharmacies in Arizona stopped filling the prescriptions he wrote. Kahn’s

practice was to provide cookie-cutter prescriptions for opioids and other

controlled substances to patients for a flat “office visit” fee. Aplt. App. II

at 50–51. By the time he had moved his practice to Wyoming, he would hand

out 30-day prescriptions for “120 oxycodone 15[milligram]s and

120 oxycodone 30[milligram]s” for $500. Aplt. App. XIV at 49.

According to Dr. Gina Moore, a medical expert who testified for the

Government at Kahn’s trial, oxycodone is a type of opioid pain medication.

The medical community measures the effects of opioid medication against

morphine, using a standard called morphine milligram equivalents (MME).

A daily dose of greater than 100 MME is associated with a risk of overdose

and addiction and the Center for Disease Control Guidelines in place at the

time of these events recommended that prescriptions for greater than

90 MME be avoided. For oxycodone, 90 MME per day would translate to

about 2 tablets of 30mg strength. By comparison, a 30-day prescription of

120 oxycodone 30mg pills and 120 oxycodone 15mg pills was 270 MME. In

some cases, Kahn wrote prescriptions for oxycodone at as high as 950 MME.

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Additionally, the likelihood of developing dependency on opioids

increases dramatically when the supply of an opioid prescription is for five

days or greater. Kahn’s prescriptions were routinely written for a 30-day

supply, with many patients receiving such a prescription monthly. 1

He would provide these prescriptions proportional to the amount that

patients would pay. His patients would commonly pay for the prescriptions

in cash and sometimes with goods, for which he had a bartering system. For

example, Kahn testified during trial that he “received firearms for medical

services.” Aplt. App. XX at 216.

Kahn’s brother, Nabeel, enforced payment at the Arizona clinic while

it was still operating. Kahn testified that he “used” Nabeel as his

“boogeyman,” Aplt. App. XIX at 134, to “scare certain people.” Aplt. App. XX

at 217. Nabeel also helped Kahn create a contract called a Drug Addiction

Statement, which all patients had to sign. It purported to make patients

swear that Kahn wasn’t a “drug dealer,” that the patient wasn’t an “addict,”

1 As will be explained in more detail later, one of Kahn’s challenges

on appeal relates to his conviction for engaging in a continuing criminal enterprise, which, at the risk of over-simplification, requires that he unlawfully engaged in and led the distribution of controlled substances with at least five other co-conspirators. It is helpful to compare Kahn’s prescriptions to more routine oxycodone prescriptions to understand the permissible universe of inferences the jury could make about his prescribing habits and about the mental state of those with knowledge of his prescribing habits.

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and it provided for a $100,000 monetary penalty for each civil or criminal

action taken against Kahn or his “officers and agents” because of something

the patient did or caused. Aple. Supp. App. II at 119.

Kahn would often write prescriptions without seeing patients first or

performing medical exams. He would at times direct Nabeel, Lyn, and

others to provide patients with their prescriptions and collect payment

while he was out of town. At least three of his patients brought new patients

to Kahn’s clinics and would pay for their prescriptions and other fees. Kahn

would sometimes negotiate prices directly with the three who were bringing

new patients in without examining the new patients. When his practice in

Arizona came under investigation by the Medical Board, he and his wife

Lyn padded patient files with falsified information to make it look like he

had performed adequate medical care and evaluations prior to writing the

prescriptions. One woman, Jessica Burch, died after snorting crushed

oxycodone pills prescribed to her by Kahn.

A grand jury returned a third superseding indictment against Kahn

charging him with: one count of conspiracy to dispense and distribute

controlled substances resulting in death, one count of possession of a

firearm in furtherance of a federal drug trafficking crime, eight counts of

unlawful dispensing of a controlled substance via unauthorized

prescription, three counts of aiding and abetting via unauthorized

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prescription the possession of a controlled substance with intent to sell, five

counts of unlawful use of a telephone to facilitate the unlawful dispensing

of a controlled substance, one count of engaging in a continuing criminal

enterprise, and two counts of money laundering. 2

Kahn was convicted of several charges after his first jury trial.

However, the convictions were later vacated after the Supreme Court held

in Ruan v. United States that the mens rea of the statute underlying most

of the convictions, 21 U.S.C. § 841, applied to the “except as authorized”

language within the statute and that a medical professional could not be

held criminally liable unless they knew they were not authorized to

prescribe or to fill the prescription. 597 U.S. 450, 454 (2022). On remand

from the Supreme Court, this court vacated Kahn’s convictions and

2 Specifically, Kahn was charged as follows: one count of conspiracy to

dispense and distribute oxycodone, alprazolam, hydromorphone, and carisoprodol resulting in death (Count 1), 21 U.S.C. §§ 846, 841(a)(1), (b)(1)(C) & (b)(2); one count of possession of firearms in furtherance of a federal drug trafficking crime, 18 U.S.C. § 924(c)(1); five counts of dispensing of oxycodone, 21 U.S.C. §§ 841(a)(1) & (b)(1)(C); three counts of aiding and abetting possession with intent to distribute oxycodone, 21 U.S.C. §§ 841(a)(1) & (b)(1)(C), 18 U.S.C. § 2; five counts of unlawful use of a communication facility, 21 U.S.C. § 843(b); three counts of aiding and abetting the dispensing of oxycodone, 21 U.S.C. §§ 841(a)(1) & (b)(1)(C), 18 U.S.C. § 2; one count of engaging in a continuing criminal enterprise (Count 21), 21 U.S.C. § 848(a), (b), & (c); and two counts of engaging in monetary transactions derived from specified unlawful activity, 18 U.S.C. § 1957. Kahn’s sufficiency of the evidence challenges on appeal relate only to Counts 1 and 21, but his other challenges relate to all counts charged under 21 U.S.C. § 841.

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remanded back to the district court for a new trial because the error

“infected the instructions given on all counts” and was not harmless. United

States v. Kahn, 58 F.4th 1308, 1322 (10th Cir. 2023).

Upon retrial, Kahn was convicted by the jury on seventeen of twentyone counts. He was found not guilty on three of the eight counts of unlawful

dispensing of a controlled substance via unauthorized prescription and on

one of the five counts of unlawful use of a telephone to facilitate the

unlawful dispensing of a controlled substance. He moved for judgment of

acquittal or for a new trial, but the district court denied his motion.

Thereafter he was sentenced to 48 months for the four counts of unlawful

use of a telephone, 120 months for the two money laundering counts, and

240 months for the remaining ten counts, these sentences to be served

concurrently, and five years as to the firearm possession count, to be served

consecutively to all other sentences. Thus, his aggregated sentence was for

300 months or 25 years’ imprisonment. His terms of supervised release are

to be served concurrently upon his release, with five years being the longest

term.

II

Kahn now brings several claims of error on appeal. He contends that

the district court erred by allowing the Government’s expert witnesses to

“opine about the law governing [] prescriptions” and by denying his motion

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for judgment of acquittal or for new trial and finding sufficient evidence to

support the jury’s verdict of guilty for the counts of unlawful distribution

resulting in death and continuing criminal enterprise. Op. Br. at 6. He also

contends that a DEA-registered prescriber, as a legal matter, cannot be held

criminally liable under 21 U.S.C. § 841. We will address each claim of error

in turn.

A

Kahn first challenges the admission of testimony from the

Government’s expert witnesses. 3 He argues the expert testimony amounted

to “improper legal opinions regarding the scope of a registrant-physician’s

prescribing authority.” Op. Br. at 26.

We review the “admission of expert testimony” for abuse of discretion.

United States v. Miller, 891 F.3d 1220, 1226 (10th Cir. 2018) (quoting

United States v. Varma, 691 F.2d 460, 463 (10th Cir. 1982)). “The district

court abuses its discretion if the court’s decision ‘is arbitrary, capricious,

3 The Government argues this challenge is waived and precluded by

the law of the case doctrine. We need not address the Government’s arguments on these points because Kahn’s challenges to the testimony fail on the merits. See United States v. Wells, 873 F.3d 1241, 1250 (10th Cir. 2017) (declining to reach waiver issue where substantive argument failed on the merits); McIlravy v. Kerr-McGee Coal Corp., 204 F.3d 1031, 1035 (10th Cir. 2000) (Law of the case doctrine is “only a rule of practice in the courts and not a limit on their power.” (quoting United States v. Monsisvais, 946 F.2d 114, 116 (10th Cir. 1991)).

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whimsical or manifestly unreasonable, or when we are convinced that the

district court made a clear error of judgment or exceeded the bounds of

permissible choice in the circumstances.’” United States v. Chapman,

839 F.3d 1232, 1237 (10th Cir. 2016) (quoting United States v. MedinaCopete, 757 F.3d 1092, 1100–01 (10th Cir. 2014)).

Although Kahn does not point to any Federal Rule of Evidence that

he argues should sustain his objection, we assume he raises Rule 702 error.

Under Rule 702, the trial court must exercise a gatekeeping function on

expert testimony, allowing an expert to testify only if it is more likely than

not that “the expert’s scientific, technical, or other specialized knowledge

will help the trier of fact to understand the evidence or to determine a fact

in issue.” Fed. R. Evid. 702(a). For this reason, an expert witness cannot

“define the legal parameters within which the jury must exercise its factfinding function.” Specht v. Jensen, 853 F.2d 805, 809–10 (10th Cir. 1988)

(en banc). However, expert witnesses may still “refer to the law in

expressing an opinion without that reference rendering the testimony

inadmissible.” Id. at 809. “[A] witness may properly be called upon to aid

the jury in understanding the facts in evidence even though reference to

those facts is couched in legal terms.” Id. For example, “a court may permit

an expert to testify that a certain weapon had to be registered with” a

federal agency, as well as permit “a medical expert [to] testify[] that specific

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conduct constitutes medical malpractice.” Id. at 809–10. But a court may

not permit an expert to testify to legal conclusions, such as that

“warrantless searches are unlawful” or that “a warrantless search” was

conducted. Id. at 808.

Here, the challenged testimony was offered as evidence to prove the

mens rea element for the charges against Kahn under 21 U.S.C. § 841(a)(1),

which prohibits “any person knowingly or intentionally” from

“manufactur[ing], distribut[ing], or dispens[ing], or possess[ing] with intent

to manufacture, distribute, or dispense, a controlled substance” except as

authorized. 21 U.S.C. § 841(a)(1). The Supreme Court held in Ruan v.

United States that 21 C.F.R. § 1306.04(a), the regulation that defines the

proper purposes to issue prescriptions, “defin[es] the scope of a doctor’s

prescribing authority” using reference “to objective criteria such as

‘legitimate medical purpose’ and ‘usual course’ of ‘professional practice.’”

597 U.S. at 467 (quoting 21 C.F.R. § 1306.04(a)). The Supreme Court also

held that “[t]he Government . . . can prove knowledge of a lack of

authorization through circumstantial evidence,” including evidence

showing that the defendant failed to meet the “objective criteria” underlying

§ 1306.04. Id. (noting “‘the more unreasonable’ a defendant’s ‘asserted

beliefs or misunderstandings are,’ especially as measured against objective

criteria, ‘the more likely the jury . . . will find that the Government has

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carried its burden of proving knowledge” (alteration in original) (quoting

Cheek v. United States, 498 U.S. 192, 203–04 (1991)).

Kahn challenges testimony from the Government’s witnesses where

they “claim[ed] that . . . § 1306.04 defines the scope of a practitioner’s

authorization” and quoted language from § 1306.04, including the phrases

“legitimate medical purpose” and “usual course of professional treatment.”

Op. Br. at 26. He also challenges Dr. Jed Shay’s testimony, elicited from his

counsel on cross examination, that “a licensed physician who exercises

judgment in a way that deviates from standard practices in the medical

community is ‘just as guilty’ as one with a suspended medical license.” Id.

(quoting Aplt. App. VIII at 123–24).

The district court did not err by allowing this testimony. Ruan

explains that the language of § 1306.04 can be used to assist the jury in

evaluating evidence that goes to the “lack of authorization” element of

§ 841. 597 U.S. at 467. Furthermore, testimony from medical experts that a

defendant’s medical treatment of their patients was “illegitimate or

inappropriate,” as here, “falls within the limited vernacular that is

available to express whether a doctor acted outside the bounds of his

professional practice” and thus doesn’t have a sufficiently “specialized”

legal meaning that renders the testimony inadmissible. United States v.

McIver, 470 F.3d 550, 562 (4th Cir. 2006); accord United States v. Schneider,

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704 F.3d 1287, 1294 (10th Cir. 2013) (“The concern . . . is when an expert

uses a specialized legal term and usurps the jury’s function. The use of the

phrase ‘other than legitimate medical purposes’ does not cause such a

problem.”); United States v. Chube II, 538 F.3d 693, 698 (7th Cir. 2008)

(“When all is said and done, we agree with the Government that it is

impossible sensibly to discuss the question whether a physician was acting

outside the usual course of professional practice and without a legitimate

medical purpose without mentioning the usual standard of care.”); see also

United States v. MacKay, 715 F.3d 807, 838 (10th Cir. 2013) (no error where

expert used the phrases “cause of death” and “death resulted from” during

her testimony where “she explained her observation based on the evidence

in the case” instead of “tell[ing] the jury [the defendant] was guilty”).

Kahn argues that authorization is “not a peripheral legal concept[,]

. . . [i]t [is] the central dividing line between lawful medical practice and

federal felony liability.” Reply Br. at 8. We disagree with this argument

because the dividing line between lawful medical practice and federal felony

liability is the mens rea requirement in § 841(a)(1), which is to knowingly

and intentionally commit the actus reus without authorization. Ruan,

597 U.S. at 467.

Finally, it should be noted that the testimony Kahn most strenuously

objects to, that a licensed physician who deviates from standard medical

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practice is “just as guilty” as one practicing without a valid license, was

elicited by Kahn’s own counsel on cross-examination and was not objected

to at the time by either party. “[A] party who induces an erroneous ruling”

is prevented “from being able to have it set aside on appeal.” United States

v. Burson, 952 F.2d 1196, 1203 (10th Cir. 1991). This testimony appears to

be invited error, or at least waiver, and Kahn does not argue for plain error

review of this testimony in his briefs. This court therefore will not consider

that testimony as part of Kahn’s appellate argument. See United States v.

Leffler, 942 F.3d 1192, 1196 (10th Cir. 2019). In sum, there was no Rule 702

error.

B

In the district court, Kahn moved for acquittal or a new trial pursuant

to Federal Rules of Criminal Procedure 29 and 33, which was denied. Kahn

now challenges the district court’s denial of that motion. Specifically, he

challenges the sufficiency of the evidence as to Count 1, conspiracy to

dispense and distribute oxycodone, alprazolam, hydromorphone, and

carisoprodol resulting in death, 21 U.S.C. §§ 846, 841(a)(1), (b)(1)(C), and

(b)(2), and Count 21, continuing criminal enterprise (CCE), 21 U.S.C. § 848.

Both offenses carry substantial mandatory minimum sentences. See

21 U.S.C. §§ 841(b), 848(a).

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“We review de novo the district court’s denial” of a Rule 29 motion.

United States v. Hamilton, 587 F.3d 1199, 1205 (10th Cir. 2009). “In

reviewing the sufficiency of the evidence, we consider all the evidence in the

light most favorable to the prosecution and determine whether ‘any rational

trier of fact could have found the essential elements of the crime beyond a

reasonable doubt.’” United States v. Lowe, 117 F.4th 1253, 1270 (10th Cir.

2024) (quoting Jackson v. Virginia, 443 U.S. 307, 319 (1979)). “We may

reverse only if no rational trier of fact” could have found the Government

met its burden of proof. United States v. King, 632 F.3d 646, 650 (10th Cir.

2011) (emphasis added) (quoting United States v. Ramos-Arenas, 596 F.3d

783, 786 (10th Cir. 2010)).

Kahn was convicted of engaging in a CCE, charged under 21 U.S.C.

§ 848, related to the unauthorized dispensing of oxycodone and other

controlled substances, in violation of various subsections of 21 U.S.C. § 841.

The Government thus had the burden of proving the following elements

beyond a reasonable doubt at trial: (1) Kahn violated § 841; (2) the

violations were part of a continuing series of violations; (3) Kahn committed

the violations in concert with five or more persons with respect to whom he

occupied a position of organizer, supervisor, or other position of

management; and (4) from which he obtained substantial income or

resources. See 21 U.S.C. § 848(c).

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Here, Kahn contests only one element: that the Government adduced

sufficient evidence to show that he committed the violations in concert with

five or more persons and that he occupied the requisite managerial role over

such persons. The district court found that Kahn exercised a managerial

role over at least seven co-conspirators: (1) Nabeel Khan, his brother;

(2) Lyn Kahn, his wife; (3) Stacy Drndarski, a front desk receptionist at

Kahn’s Arizona clinic and a patient; (4) David Drndarski, Stacy’s husband

and a patient; (5) Christopher Muelhausen, a patient; (6) Paul Beland, a

patient; and (7) Deni Antelope, a patient. The Government, for its part,

argues that it put forward enough evidence to prove that Kahn exercised a

managerial role over the seven people just discussed plus Jessica Burch and

her partner Anthony Vargas, for a total of nine co-conspirators. On appeal,

Kahn argues that Lyn and Nabeel did not have the “requisite state of mind”

necessary to be considered co-conspirators, and that he did not exercise a

managerial role over Nabeel, the Drndarskis, Muelhausen, Beland, and

Antelope. Op. Br. at 39–40.

Kahn’s arguments are not persuasive. On this record, the district

court was correct to find that, at the very least, six individuals – Lyn,

Nabeel, Stacy, Muelhausen, Beland, and Antelope – acted in concert with,

and under the control of Kahn to sell unauthorized prescriptions for

controlled substances. We will begin with the applicable law and then

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proceed to analyze Kahn’s arguments as to each co-conspirator in turn, first

reviewing the evidence that was adduced at trial for each.

Again, to sustain a conviction for a CCE under § 848, otherwise known

as the kingpin statute, the Government must prove beyond a reasonable

doubt that Kahn committed the underlying violations in concert with five

or more persons and that he occupied a position of organizer, supervisor, or

other position of management. The phrase “in concert with” means that “[a]

conspiracy is . . . a necessary part of a CCE violation” and requires some

“proof of an agreement among the persons involved in the [CCE].” United

States v. Allen, 24 F.3d 1180, 1186 (10th Cir. 1994) (quoting Jeffers v.

United States, 432 U.S. 137, 149–50 (1977)). To establish the existence of a

conspiracy, the Government must prove that there was a “joint commitment

to an ‘endeavor which, if completed, would satisfy all of the elements of the

underlying substantive criminal offense.’” Ocasio v. United States, 578 U.S.

282, 287 (2016) (quoting Salinas v. United States, 522 U.S. 52, 65 (1997))

(alterations accepted). It is sufficient that the Government proves the

“conspirators have a plan which calls for some conspirators to perpetrate

the crime and others to provide support.” Id. at 288 (quoting Salinas,

522 U.S. at 64). What follows then is that “innocent participants in criminal

activity may not be counted as part of a continuing criminal enterprise.”

United States v. Smith, 24 F.3d 1230, 1234 (10th Cir. 1994). But the

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Government also need not “prove an express or formal agreement” was

reached to perpetrate the crime; rather, it is sufficient that the Government

proves the existence of a “mutual understanding” to do so. United States v.

Rutland, 705 F.3d 1238, 1250 (10th Cir. 2013) (quoting United States v.

Suntar Roofing, Inc., 897 F.2d 469, 474 (10th Cir. 1990)). Circumstantial

evidence is “sufficient to prove the existence of” such a mutual

understanding. United States v. Brooks, 736 F.3d 921, 938 (10th Cir. 2013).

Once it is shown that Kahn acted in concert with five or more persons,

the Government must also prove that Kahn was an organizer, supervisor,

or occupied some other position of management over his co-conspirators.

United States v. Apodaca, 843 F.2d 421, 425–26 (10th Cir. 1988). The terms

“organizer, supervisor, or manager” are not technical and should be given

their ordinary meaning. Id. The statute’s language is disjunctive and

denotes “differing levels of managerial control and coordination.” Id. at 426.

An organizer, for instance, is a person who “puts together a number of

people engaged in separate activities and arranges them in their activities

in one essentially orderly operation or enterprise” and need not necessarily

be “able to control those whom he or she organizes.” Id. (first quoting

2 E. Devitt & C. Blackmar, Federal Jury Practice and Instructions § 58.21

(1977), and then quoting United States v. Ray, 731 F.2d 1361, 167 (9th Cir.

1984)). “[T]he defendant need not have had personal contact with each of

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the five persons involved . . . [n]or must each transaction with or instruction

to those persons organized or managed specifically originate with the

defendant,” as “mere delegation” of duties is enough. Id. Thus, a “defendant

may not insulate himself from liability by delegating authority.” United

States v. McSwain, 197 F.3d 472, 479 (10th Cir. 1999). However, “a mere

buyer-seller relationship, without more, [is] insufficient to establish that

[the defendant] held some managerial role with respect to” the coconspirators. Apodaca, 843 F.2d at 426. We now apply these legal principles

to the co-conspirators.

Nabeel Khan. Nabeel helped manage Kahn’s Arizona clinic,

discussed office visit pricing with Kahn, advised patients of the prices for

their prescriptions, drafted the Drug Addiction Statement that patients

were required to sign, provided prescriptions and collected payment when

Kahn was out of town, and was Kahn’s “boogeyman” who enforced payment

when patients tried to negotiate price reductions. Aplt. App. XX at 217.

Nabeel stopped working at the Arizona clinic when Kahn moved his practice

to Wyoming but would still discuss pricing with Kahn. At times, Nabeel

would also accept payment from Arizona-based patients, like Stacy and

David, either in person from those who were traveling to Wyoming or

through the mail from others. Nabeel similarly provided prescriptions to

Christopher Muelhausen when Kahn was out of town. Once, Kahn discussed

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with Nabeel over the phone that two patients hadn’t reimbursed him for

their prescription because they didn’t have the money and then “told Nabeel

that he may have [another] patient that may want to buy them.” Aplt. App.

XVI at 33. And Kahn stored the cash he collected from patients in “the house

that h[e] and Nabeel lived in” located in Arizona. Id. at 48.

Kahn asserts that Nabeel’s behavior as described here was simply the

performance of normal office duties, so Nabeel cannot be considered a CCE

participant because he did not have the “requisite state of mind.” Op. Br.

at 40. For the same reasons, Kahn asserts Nabeel was not his supervisee.

On the contrary, the record evidence here amply supports a finding that

Nabeel was a CCE participant and that Kahn exercised some position of

management over him. Nabeel appeared to be acting as a second in

command to Kahn, at the very least helping to set prices for prescriptions

and continuing to accept cash payment and provide prescriptions to patients

still located in Arizona after Kahn’s practice moved to Wyoming. The

unusual nature of the prescriptions, paired with the payment made in cash

or in goods or services, and done without a connection to medical care, at

least circumstantially shows that Nabeel had a “mutual understanding” to

engage with Kahn in the illicit sale of prescriptions for controlled

substances. Rutland, 705 F.3d at 1250 (citation omitted). Nabeel did all this

at the direction of Kahn, who quite literally was Nabeel’s employer as the

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owner of the Arizona clinic. It is difficult to imagine a clearer case of a

position of management over another than the relationship of employer to

employee. And Kahn never argues that Nabeel engaged in this conduct

without his knowledge or approval.

Lyn Kahn. Lyn managed Kahn’s Wyoming clinic. Lyn pled guilty to

conspiring with Kahn “and others to commit the illegal diversion of

prescription drugs.” Aplt. App. II at 58. She testified for the Government at

trial. She testified that Kahn wrote prescriptions in the name of her

daughter, Shaina, and that Lyn filled these prescriptions, picked them up

herself, and gave them to Kahn so he could give them to Nabeel. She

testified that she filled patients’ prescriptions in Wyoming with the

knowledge that Kahn had not provided any medical care or evaluation and

then would send the drugs through the mail to where the patients resided

in Arizona. Sometimes those patients would travel to Wyoming from

Arizona or elsewhere and stay at her home while they filled their

prescriptions. For example, she testified that she and Kahn provided a

letter indicating proof of residency at her home in Wyoming to Stacy

Drndarski so Stacy could obtain a Wyoming driver’s license to “help her . . .

get her meds” more easily after a local pharmacy “stopped filling

[prescriptions] for [Kahn’s] patients.” Aplt. App. XVI at 29.

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Once, she watched Kahn remove the labels from a patient’s

prescription before she sent them via FedEx to a different patient who then

“sent money” back to them “a day or so later.” Id. at 35. She was aware that

Kahn’s practice was “cash-only” and that he “traded office visits for guns”

and a “Harley-Davidson motorcycle,” among other things. Aplt. App. XV

at 256–58. Finally, she helped Kahn add false information to patient files

when the Arizona Medical Board began investigating Kahn’s practice “to

make the chart[s] look better” by indicating that Kahn had provided medical

care to patients when he had, in fact, not. Id. at 292.

Kahn argues that Lyn did not believe Kahn was doing anything wrong

at the time of these events and so she did not have the requisite criminal

intent to be considered a CCE participant. This argument is rendered

nearly frivolous by the fact that Lyn pled guilty to engaging in a criminal

conspiracy with Kahn to illegally divert prescription drugs – thereby

admitting under oath to having the requisite criminal intent to be Kahn’s

co-conspirator for purposes of the CCE. See Allen, 24 F.3d at 1186. Even

without the guilty plea, the record evidence here strongly supports, even

more so than Nabeel, the conclusion that Lyn was a participant in the CCE.

Stacy and David Drndarski. Stacy and her husband David were

initially Kahn’s patients in Arizona. Stacy testified that, at her first visit,

Kahn tried to “get[] to know [her] and . . . what [her] needs were . . .

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medically.” Aplt. App. XI at 79. But she also testified that Kahn prescribed

her benzodiazepines, muscle relaxants, sleep medication, and opioids like

Percocet and oxycodone during her first two visits without counseling her

on side effects and, in some instances, without her having requested the

specific medication. Once she began working for Kahn, she testified, “he

didn’t really ask . . . questions anymore” and instead just handed her the

prescriptions “when [they] were leaving work.” Id. at 79, 132.

Stacy became Kahn’s employee at his Arizona clinic, and the cost of

her prescriptions eventually came out of her paycheck once she was unable

to afford cash payments. There were no set hours at the clinic, and Stacy

would be responsible for setting up appointments with patients for their

next visits. She noticed that Kahn saw pain management patients for

“maybe 5, 10 minutes” at a time. Id. at 95. Stacy also would be “given a list

to call patients” to inform them of price increases for their next visit, “[a]nd

the amount was next to their name” for her to reference. Id. at 82. Stacy

would also provide prescriptions to patients “if they came in and paid” at

the direction of Kahn. Id. at 82–83. Stacy was aware that other patients

paid in cash and sometimes traded office visits for other things of value. For

instance, she testified that a man who worked at a “tire shop” traded “tires

for a vehicle of . . . Kahn’s” for prescriptions. Id. at 91. She was also aware

that patients were paying for, or “sponsoring,” other patients’ prescriptions,

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and that Kahn would give one patient all the prescriptions for multiple

people and accept payment for all from that one patient. Id. at 101. Her

husband David, also a patient of Kahn’s, provided prescriptions to one of

Kahn’s patients in the parking lot of the Arizona clinic and received cash

payment for it while Stacy waited in the car nearby. She was present when

David traded “a Harley and some guns” with Kahn as payment for their

prescription medication. Id. at 87. Eventually, David began to sell his and

Stacy’s medications to pay for their visits with Kahn. When pharmacies in

Arizona stopped filling prescriptions written by Kahn, he asked Stacy to

“record it when [she] would go up to the pharmacist to fill [a] prescription

to see what they would say,” which she agreed to and did. Id. at 138. The

pharmacists would tell her that they had “issues with this . . . particular

doctor.” Id. at 139.

Stacy and David helped Kahn move his practice to Wyoming, and

Stacy stopped working for Kahn once he did. Stacy began to travel to

Wyoming to get her and David’s medications. Sometimes, she would still

pick up prescriptions from Kahn when he came back to Arizona or from

Nabeel at his home. When authorities “raided” Kahn’s home and Nabeel’s

home, Lyn contacted Stacy and informed her of the searches and “asked . . .

if [she] had any contact with the police.” Id. at 199–200. Stacy and David’s

home was searched by authorities shortly thereafter.

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Kahn asserts that Stacy and David did not have a conspiratorial

agreement with Kahn and were not his supervisees. Yet again, this

argument is belied by the record evidence, which proved that Stacy and

David both personally knew that Kahn was selling prescriptions for

unusually high amounts of oxycodone and other substances for cash or

goods, and facilitated this by trading prescriptions for cash in a parking lot

and monitoring the actions of local pharmacists at his direction. And again,

Stacy was his employee at his Arizona clinic, primarily tasked with calling

patients to inform them that the prescription prices were going up for

certain medications. We quite easily agree with the district court that the

Drndarskis qualify as CCE co-conspirators with Kahn.

Christopher Muelhausen. Muelhausen was a pain patient of Kahn’s

for years and at the height of his addiction was using about 20 oxycodone

pills per day. He sold the medication he didn’t use himself to pay for his

visits with Kahn. For instance, during his visits with Kahn, he would often

request and be prescribed medications such as Soma or Xanax so he could

then sell them or trade them on the street. At one point he “heard rumors

from the other patients that [Kahn] was allowing” patients to get a

prescription every two weeks rather than every thirty days, so he asked

Kahn if he could also come in every two weeks. Aplt. App. IX at 262. Kahn

agreed but told him “the price was going to change.” Id. at 263. Muelhausen

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began to go to the clinic every two weeks, and he would get the same

prescription he was originally getting for 30 days so that, in his words,

“[w]hatever I was getting prescribed . . . would be times two.” Id. At one

visit, Muelhausen wanted to talk about how high the price was for visits.

Kahn told him he knew “that [Muelhausen and others] sell them for

20 bucks on the street” and that the visits “would be th[e] amount that was

mentioned.” Id. at 265–66. Muelhausen would go to visits and be visibly

high or withdrawing from oxycodone, and Kahn would never comment about

his condition. He testified to how a typical visit with Kahn would go: “Go in,

make your payment, they would count it with a money counter, and then go

see the doctor, and he would have the prescriptions already preprinted or

written out.” Id. at 271.

Muelhausen eventually began to “sponsor” other patients at Kahn’s

clinic, which meant he brought them to their appointments, negotiated their

prescription payments for them, and sometimes helped them pay for their

prescriptions. Id. at 280. In return, he would take a cut of their medication.

For instance, Stacy testified that Muelhausen brought Jessica Burch and

her partner, Anthony Vargas, to their appointments and would sometimes

pay for them when they were not physically present at the office.

Muelhausen would call Kahn about bringing his “friend[s]” in as new

patients and Kahn would agree to see them, set up appointments, and

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inform him of the cost there on the phone without knowing who the patient

was or any of their medical history. Id. at 299. Kahn directed Muelhausen

to pick up prescriptions from the clinic for other patients and coordinated

with Muelhausen when pharmacies wouldn’t fill prescriptions for certain

patients.

Kahn argues that he wasn’t aware that Muelhausen was paying for

other patients’ visits. Kahn argues that even if he did know, that fact is

insufficient to establish a managerial role because such conduct is

“incidental” to a buyer-seller relationship. Op. Br. at 41–42 (quoting United

States v. Bass, 310 F.3d 321, 327 (5th Cir. 2002)). But Kahn did not merely

sell oxycodone prescriptions to Muelhausen. The record evidence indicates

that Muelhausen brought in new “patients” to see Kahn, who in turn would

communicate pricing to Muelhausen directly on the phone. And Kahn

directed him to pick up other patients’ prescriptions and would assist

Muelhausen when pharmacies wouldn’t fill prescriptions. Muelhausen was

akin to a street corner drug dealer, acting under the direction of the kingpin

with the prescription pad – Kahn. So were Paul Beland and Deni Antelope,

who we will discuss next.

Given that we agree with the district court there was sufficient

evidence to prove the first five people were involved in the CCE conspiracy

under Kahn’s supervision, we also affirm the conviction for this crime.

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Nevertheless, we soldier on to consider Kahn’s arguments regarding other

co-conspirators.

Paul Beland. Beland struggled with a lifelong drug addiction and

was referred to Kahn as a patient by another physician in Wyoming for pain

management for back pain. When Beland called to make an appointment,

Lyn scheduled it and told him it would cost $500. When Beland asked what

the charge was for, Lyn said “[d]on’t worry; you’ll get what you want.” Aplt.

App. V at 265–66. Beland testified that he asked for certain strengths of

oxycodone tablets at his first visit because of Kahn’s behavior. In Beland’s

words, “if he’s already going to offer me 30s and 15s and he has his back

turned to me, that’s not a doctor. . . . If he’s asking me what works for me,

I’m going to tell him the most that I can that works for me.” Id. at 285–86.

Beland would sometimes pick up his prescriptions from an employee

at a vape shop owned by Kahn, paying for them in cash and receiving the

prescriptions in a sealed envelope along with medical forms. He asked Kahn

for his prescription of 30-milligram oxycodone to be bumped up from

120 pills to 180 pills, which Kahn provided upon request without seeing

Beland or conducting an exam. Beland relocated to Massachusetts but

thereafter traveled to Wyoming to get prescriptions from Kahn.

Eventually, Kahn told Beland that he would take $50 off the cost of

his prescriptions for every pain patient Beland referred to him, up to three

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patients maximum. Beland testified that he told Kahn specifically how

many oxycodone pills each patient would be prescribed at each visit:

[T]he patient or client would get – the pills, 120 of the 30s, 120 of

the . . . 15s, the first visit. The second visit would be 180 of . . . the

30s, 180 of the 20s. And then . . . the third month, it would go up

from there to the 300s because then, by now, I’m already at that

300 [of each strength oxycodone pill]. On the third – on the fourth

visit I’m at the 300.

Aplt. App. VI at 20. Beland referred patients pursuant to this arrangement,

even going as far as to refer his partner who did not need pain medication,

so he could fill her prescriptions and take her pills for himself. After this,

Beland’s relationship with Kahn became a “business relationship” and

“grew from there.” Id. at 26. Beland testified that Kahn told him he knew

“these are being sold on the street [and he] need[ed] [a] cut” and that Beland

agreed Kahn’s cut for “300 30s [and] 180 20s” would be a thousand dollars.

Id. Beland sold some of his prescription medication to pay for travel to

Wyoming and to pay Kahn his cut of the money, and then he consumed the

rest of the medication, as well as heroin. He would call Lyn to get

appointments for new patients, tell Kahn the dosage and amount of

oxycodone he wanted, fly to Wyoming to get his cut of the medication from

the new patient, and then wire money back to Kahn. Beland testified Kahn

knew he was paying for patients’ visits because he was “wiring [Kahn] the

money . . . [via] Western Union.” Id. at 42. He would “send a chunk of

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money” to Kahn every so often as he sold the pills he was taking from the

patients for whom he was paying. Id. at 44.

In a recorded phone call, Beland spoke with Kahn about how much

oxycodone to prescribe a new patient without Kahn having ever met the

patient. Kahn told Beland that the “new guy” should be prescribed less than

Beland “because of the way things are right now.” Aple. Supp. App. II at 19.

On the same phone call, Kahn agreed to prescribe Xanax to Beland’s partner

on a one-time basis because “[this] shit [was] getting hot” and the “FDA’s

come down on Xanax and on narcotics.” Id. at 22–23. Kahn once sold Beland

prescriptions written for the Drndarskis when they couldn’t pay for them

with the knowledge that Beland would then “sell” the pills to others. Aplt.

App. XVI at 33–35. Beland sent cash to Kahn for those prescriptions

overnight through the United States Postal Service. Beland was arrested

about a year after he began seeing Kahn and ended up pleading guilty to

conspiring with Kahn to illegally divert prescription drugs.

Kahn argues that he did not have a managerial role over Beland

because there was no conspiratorial agreement that Beland would sell his

prescribed medication. Once again, we disagree. The record evidence shows

that Beland brought in at least two new patients from out of state to see

Kahn after negotiating with him on the phone about the price and amount

of the prescriptions, and that he wired or mailed cash to Kahn for these

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patients’ prescriptions. For the same reasons as discussed for Muelhausen,

there is sufficient evidence to show that Beland was under the managerial

control of Kahn for purposes of the CCE conviction.

Deni Antelope. Finally, Antelope was Kahn’s patient who, like

Beland and Lyn, also pled guilty to conspiring with him to illegally divert

prescription drugs and testified for the Government at his trial. At the time

she was Kahn’s patient, she lived in Riverton, Wyoming. She initially

sought out Kahn’s care because her sister told her that he was “giving out

oxycodone” and she wanted to obtain it to then sell it in Riverton and on

“the rez.” Aplt. App. XIV at 24. Antelope almost immediately began

sponsoring other patients’ visits to Kahn, beginning with one of her sisters

and her then-spouse. She testified that around her fourth visit, “[she] and

Dr. Kahn talked about bringing more people” in to get prescriptions from

him. Id. at 36. Kahn asked her if she “knew more people who needed pain

management” and asked if she knew the street price of oxycodone. Id. at 36–

37. Her spouse, who was in the room with her, replied that it went for about

a “dollar per milligram.” Id. at 40. By the end of the visit, Antelope had

agreed to “bring more people” in to get prescriptions from Kahn. Id. at 48.

Antelope began bringing people to whom she was selling oxycodone

for visits with Kahn. She would call Lyn to set up the appointments, bring

in the new patients, and be in the room for their first visit. Kahn would

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prescribe them “[t]he regular” dosage and amount that “he could start with,”

which was “120 oxycodone 15s and 120 oxycodone 30s.” Id. at 49. Antelope

would bring about two or three patients per day and pay the $500 for the

new patients she brought to the clinic. In return for paying for their fees

and incidentals for the trip to Kahn’s clinic, she would take 90 of the 120

pills of each strength oxycodone they were prescribed, which she would then

sell on the street. She had about 15 to 20 people who she regularly brought

to the clinic to get prescriptions. In her words, “the ones that were the most

addicted to [oxycodone] stayed with [her]” because they would run out of

money and so they needed her to pay Kahn for their pills. Id. at 64–65. She

would pay the fees for the patients in front of Lyn. In addition to bringing

new patients into the clinic, Antelope was involved with Kahn’s practice in

other ways. For example, Lyn asked her to get another patient to pay his

debt for a prescription he had received.

Kahn asserts that he did not have “any involvement with Antelope’s

pill sales” and did not have “any understanding of arrangements Antelope

might make on her own with any new patients.” Op. Br. at 42–43. But the

record evidence shows that he informed Antelope about the amount and

price of oxycodone he would sell to new patients, and he explicitly asked her

to bring him new pain management patients. Kahn cannot avoid the

common-sense conclusion that follows from these facts by using the words

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“patient” and “pain management services” instead of “addict” and “drug

dealing.” Id. at 43. The record evidence shows that he directed Antelope to

bring in new drug addicts so he could sell drugs to them at a set price. For

the same reasons as discussed for Muelhausen and Beland, there is

sufficient evidence to show that Antelope was under the managerial control

of Kahn for purposes of the CCE conviction.

In sum, the seven individuals discussed above, at a minimum, meet

the CCE element that Kahn acted in concert with “five or more other

persons.” 21 U.S.C. § 848(c)(2)(A). On the record before us, it is apparent

that Kahn was dealing oxycodone and other controlled substances using the

power of his prescription pad and his authority and status as a medical

doctor. Kahn employed Lyn, Nabeel, and Stacy (who included David) in this

endeavor, and directed all three to provide prescriptions to patients for

payment in his stead. The evidence adduced at trial supports the conclusion

that all three knew that patients were receiving prescriptions without

medical exams for cash payment – in effect, that Kahn was dealing opioid

medication to patients – and that they assisted him willingly in this

endeavor and at his direction.

Further, there is more than a mere buyer-seller relationship between

Kahn and Muelhausen, Beland, and Antelope. Kahn directed Muelhausen

to pick up prescriptions for other patients. Kahn also directly negotiated

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with Antelope and Beland about the prescription pricing for the patients

they brought into the practice, without even seeing the patients first. Even

if Kahn wasn’t involved in every oxycodone exchange or didn’t know about

every patient who these three paid for, the ”mere delegation of [his] duties”

as the person who wrote the prescriptions is enough to establish a

managerial role. Apodaca, 843 F.2d at 426. The district court was correct

when it found sufficient evidence to support the jury’s verdict of guilty for

the CCE count.

C

Kahn also challenges the sufficiency of the evidence underlying his

conviction on one count for conspiracy to distribute of oxycodone resulting

in death under 21 U.S.C. § 841(a) & (b)(1)(C) in connection with the death

of his patient, Jessica Burch. For this charge, the Government had to prove

beyond a reasonable doubt that: (1) Kahn knowingly, intentionally and

unlawfully distributed oxycodone to Jessica Burch; and (2) the oxycodone

Kahn distributed to Burch caused her death. 21 U.S.C. § 841(a) & (b)(1)(C).

Kahn contests that the Government adduced sufficient evidence to prove

that the oxycodone Kahn provided to Burch caused her death. Specifically,

he takes issue with the opinion of the Government’s expert witness,

Dr. Hail, which he challenges as “speculative” and as providing “no[]

support” for her finding that Burch died from an oxycodone overdose.

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Op. Br. at 44. Kahn’s argument mostly attacks Dr. Hail’s credibility as an

expert and the methodology she used to reach her conclusions, as well as

the information he asserts she did not properly consider. Id. at 44–48.

At a closer glance, Kahn’s argument is simply a repackaged Daubert

challenge to the admissibility of Dr. Hail’s expert testimony. However, a

Daubert challenge is not properly before this court on appeal because Kahn

does not argue for plain error in any of his briefs.

Kahn did not bring a Daubert challenge to Dr. Hail’s testimony before

the district court until his post-trial motions following the close of evidence.

Daubert challenges that come after the close of evidence, like Kahn’s, are

untimely, waived, and subject to plain error review on appeal. Macsenti v.

Becker, 237 F.3d 1223, 1233–34 (10th Cir. 2001); accord Brooks, 736 F.3d

at 932. Because Kahn does not affirmatively raise a Daubert challenge, let

alone under plain error, in his appellate briefing, such a challenge will not

be considered here. The Daubert challenge is waived, but a challenge to the

general sufficiency of the evidence underlying Kahn’s conviction on this

count is not, so we now consider sufficiency.

The evidence presented at trial concerning Jessica Burch’s death was

that she had filled a prescription for oxycodone that Kahn wrote for her

three days prior to her death, including 15-milligram oxycodone pills

manufactured by Actavis (green-colored) and that she died with green34

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colored crushed pill remnants in her nostrils. Her partner, Anthony Vargas,

testified that she normally crushed and snorted her oxycodone pills and that

she had passed out face down on their front lawn hours prior to her death.

Additionally, there was evidence that Jessica had a history of seizures and

had been hospitalized once before to be evaluated for a seizure. Jessica’s

mother also testified that she had medically died once when she had her

gallbladder removed. Dr. Hail was also called by the Government to testify

as to her expert opinion on the cause of Jessica’s death.

Dr. Hail is a medical doctor who testified for the Government as an

expert in emergency medicine and medical toxicology, with no objection

from Kahn during trial. Dr. Hail testified to her opinion regarding the cause

of death of Jessica Burch, specifically that she “would not have died but for

oxycodone.” Aplt. App. XVII at 219. In doing so, she ruled out traumatic

(e.g., gunshot wound) and natural causes of death. The primary

circumstances that led Dr. Hail to conclude that Jessica died of an

oxycodone overdose were that Jessica was a “young, healthy person who was

known to abuse her . . . medications,” that Jessica had a habit of “crush[ing]

up . . . oxycodone and snort[ing] it,” that there was “green powder present

in her nose,” and the description of her behavior “the night before she died.”

Id. at 221.

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By his telling, Kahn’s counsel conducted an “aggressive and thorough”

cross examination of Dr. Hail where, among other things, he challenged

Dr. Hail with Jessica’s medical records that indicated a history of a stomach

cancer diagnosis and a stroke. Op. Br. at 23. Dr. Hail testified that although

this history appeared in the medical records, there was no indication that a

doctor diagnosed Jessica with stomach cancer and there was no evidence

that Jessica ever had a stroke. In fact, a physician had written in Jessica’s

records that “Jessica Burch continually reports that she has stomach cancer

. . . [but] we have never found her to have anything other than chronic

abdominal pain, drug-seeking behavior, and constipation,” and the medical

records also indicated that Jessica’s history of strokes was self-reported

only. Aplt. App. XVII at 297–98. Dr. Hail also testified that Jessica’s

medical records indicated one prior episode where Jessica was taken to

Western Arizona Medical Center for a seizure, but that the medical records

indicated that Jessica’s behavior was “combative” and “inconsistent with

what one would observe . . . in somebody with a seizure disorder.” Id. at

221–23. Dr. Hail thus ruled any seizure disorder out as a possibility for

causing Jessica’s death.

On appeal, Kahn asserts that Dr. Hail’s opinion was “speculative”

because it assumed that Jessica was “young and healthy with no significant

underlying medical history.” Op. Br. at 44 (alterations and quotation

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omitted). He asserts that Jessica did, in fact, have significant underlying

medical history, including seizures, a stroke, and a cancer diagnosis, any of

which could have been a cause of Jessica’s death. To the extent Kahn asks

us to weigh the trial evidence or assess Dr. Hail’s credibility as a witness

outside of Daubert gatekeeping, that is an improper task for a reviewing

court. See United States v. Moya, 5 F.4th 1168, 1187–88 (10th Cir. 2021).

The jury had the benefit of hearing Kahn’s cross-examination of Dr. Hail as

to the issues he raises on appeal and found that Burch died because of the

oxycodone that Kahn prescribed her. On this record, there is no justification

or reason to disturb the jury’s verdict on this count.

D

Finally, Kahn argues that the medical regulation that covers the

proper purposes for prescribing controlled substances, 21 C.F.R. § 1304.06,

should have no bearing on criminal liability under the drug distribution

counts he faced, charged under 21 U.S.C. § 841(a)(1). Kahn was convicted

of ten drug distribution counts, which prohibit, “[e]xcept as authorized

. . . [,] any person knowingly or intentionally” from “manufactur[ing],

distribut[ing], or dispens[ing], or possess[ing] with intent to manufacture,

distribute, or dispense, a controlled substance.” 21 U.S.C. § 841(a)(1)

(emphasis added). Section 1306.04(a) is a regulation “defining the scope of

a doctor’s prescribing authority. . . by reference to objective criteria such as

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‘legitimate medical purpose’ and ‘usual course’ of ‘professional practice.’”

Ruan, 597 U.S. at 467 (quoting regulation). Kahn’s argument is that, under

the plain text of § 841, “a DEA-registered prescriber is authorized to issue

prescriptions . . . and cannot be prosecuted under that subsection,” and thus

the scope of his prescribing authority under § 1306.04 is legally irrelevant.

Op. Br. at 55. And since Kahn was a DEA-registered prescriber, as his

argument goes, his convictions are per se invalid.

The problem for Kahn is that the Supreme Court has already decided

this issue decades ago. In United States v. Moore, the Supreme Court held

that physicians registered under the Controlled Substances Act “can be

prosecuted under § 841 when their activities fall outside the usual course

of professional practice.” 423 U.S. 122, 124 (1975). And, as stated earlier, in

Ruan v. United States, the Supreme Court noted that § 1306.04 could help

the Government “prove knowledge of a lack of authorization through

circumstantial evidence . . . by reference to objective criteria such as

‘legitimate medical purpose’ and ‘usual course’ of ‘professional practice.’”

597 U.S. at 467 (quoting regulation). Kahn argues that Moore was wrongly

decided, but this court must follow Supreme Court precedent and reject his

argument.

AFFIRMED.

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