PUBLISH 

UNITED STATES COURT OF APPEALS 

FOR THE TENTH CIRCUIT 

_________________________________ 

UNITED STATES OF AMERICA, 

 Plaintiff - Appellee, 

v. 

SHAKEEL KAHN, 

 Defendant - Appellant. 

No. 19-8054 

_________________________________ 

Appeal from the United States District Court 

for the District of Wyoming 

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

_________________________________ 

Submitted on the briefs:*

Beau B. Brindley and Blair T. Westover, Chicago, Illinois, for Appellant. 

Nicholas Vassallo, Acting United States Attorney, Stephanie I. Sprecher, Assistant 

United States Attorney, and David A. Kubichek, Assistant United States Attorney, Office 

of the United States Attorney for the District of Wyoming, Casper, Wyoming, for 

Appellee. 

_________________________________ 

Before MATHESON, BRISCOE, and CARSON, Circuit Judges. 

_________________________________ 

BRISCOE, Circuit Judge. 

*

 After examining the briefs and appellate record, this panel has determined 

unanimously that oral argument would not materially assist in the determination of this 

appeal. See Fed. R. App. P. 34(a)(2); 10th Cir. R. 34.1(G). The case is therefore ordered 

submitted without oral argument. 

FILED 

United States Court of Appeals 

Tenth Circuit 

February 3, 2023

Christopher M. Wolpert 

Clerk of Court

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_________________________________ 

This case comes before the court on remand from the United States Supreme 

Court. Doctor Shakeel Kahn (Dr. Kahn) was convicted in the United States District Court 

for the District of Wyoming, in part, for dispensing controlled substances not “as 

authorized,” in violation of the Controlled Substances Act (the CSA), 21 U.S.C. § 841(a). 

Included in his appeal to this court was his contention that the jury instructions issued by 

the district court improperly advised the jury regarding the mens rea requirement of 

§ 841(a). We affirmed Dr. Kahn’s convictions, rejecting not only his challenge to the 

instructions given, but also his challenges to multiple searches and the evidence seized. In 

upholding the instructions, we relied on our prior precedent, United States v. Nelson, 

383 F.3d 1227 (10th Cir. 2004), and further reaffirmed its holding, which was guided by 

21 C.F.R. § 1306.04(a).

Dr. Kahn appealed to the Supreme Court, raising only his instructional challenge. 

The Supreme Court held that § 841(a)’s “knowingly or intentionally” mens rea applies to 

the “except as authorized” clause of the statute, vacated our judgment, and remanded the 

case for further proceedings consistent with its opinion. Ruan v. United States, 142 S. Ct. 

2370 (2022).1

 The parties have submitted supplemental briefing, and the matter is now 

ripe for decision. 

1

 The Supreme Court consolidated Dr. Kahn’s appeal with that of Xiulu Ruan. 

Ruan, 142 S. Ct. at 2375 (“In each of these two consolidated cases, a doctor was 

convicted under § 841 for dispensing controlled substances not ‘as authorized.’”). 

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Exercising jurisdiction under 28 U.S.C. § 1291, we conclude that the jury 

instructions issued in Dr. Kahn’s trial incorrectly stated the mens rea requirement of 

§ 841(a) and, further, that such error was not harmless beyond a reasonable doubt. This 

prejudicial error infected all of Dr. Kahn’s convictions. Therefore, we VACATE Dr. 

Kahn’s convictions on all counts and REMAND for new trial. 

I. FACTS

A. Background 

In 2008, Dr. Kahn, a medical doctor, opened a practice in Fort Mohave, Arizona. 

Later that year, his brother Nabeel, who is not a medical doctor, arrived in Arizona and 

began assisting Dr. Kahn in managing his practice. Thereafter, Dr. Kahn’s practice 

shifted towards pain management. Beginning in late 2012, pharmacies in the Fort 

Mohave area began refusing to fill prescriptions issued by Dr. Kahn. In 2015, Dr. Kahn 

opened a second practice in Casper, Wyoming. During that time, Dr. Kahn continued to 

travel to Arizona to see patients; other patients travelled to Wyoming to see Dr. Kahn. Dr. 

Kahn’s wife, Lyn, began acting as office manager for Dr. Kahn’s Wyoming practice. 

By 2016, the government was investigating Dr. Kahn’s prescribing practices. 

After law enforcement executed a search warrant on Dr. Kahn’s Arizona residence, the 

government indicted him on the following charges: 

 Conspiracy to Dispense and Distribute Oxycodone, Alprazolam, 

Hydromorphone, and Carisoprodol Resulting in Death, in violation of 

21 U.S.C. §§ 846, 841(a)(1), (b)(1)(C), and (b)(2) (Count One); 

 Possession of Firearms in Furtherance of a Federal Drug Trafficking Crime, 

in violation of 18 U.S.C. § 924(c)(1) (Count Two); 

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 Dispensing of Oxycodone, in violation of 21 U.S.C. §§ 841(a)(1) and 

(b)(1)(C) (Counts Four, Six, Seven, Sixteen, and Twenty); 

 Possession with Intent to Distribute Oxycodone and Aid and Abet, in 

violation of 21 U.S.C. §§ 841(a)(1) and (b)(1)(C) and 18 U.S.C. § 2 

(Counts Five, Nine, and Ten); 

 Unlawful Use of a Communication Facility, in violation of 21 U.S.C. 

§ 843(b) (Counts Eight, Twelve, Thirteen, Seventeen, and Eighteen); 

 Dispensing of Oxycodone and Aid and Abet, in violation of 21 U.S.C. 

§§ 841(a)(1) and (b)(1)(C) and 18 U.S.C. § 2 (Counts Eleven, Fourteen, 

and Nineteen); 

 Continuing Criminal Enterprise, in violation of 21 U.S.C. § 848(a), (b) 

and (c) (Count Twenty One); 

 Engaging in Monetary Transactions Derived from Specified Unlawful 

Activity, in violation of 18 U.S.C. § 1957 (Counts Twenty Two and Twenty 

Three); 

Aplt. App., Vol. I at 45. 

B. Trial and Jury Instructions 

Lyn pleaded guilty to the conspiracy charge against her. Dr. Kahn and Nabeel, 

however, moved to suppress evidence seized in the searches of Dr. Kahn’s homes and 

businesses. The district court denied the motion (except that it suppressed the seizure of 

any automobiles), and the case proceeded to trial. 

After the close of evidence, the district court gave the following instructions to the 

jury pertaining to the 21 U.S.C. §§ 841(a)(1) and (b)(1)(C) charges in Counts Four, Six, 

Seven, Eleven, Fourteen, Sixteen, Nineteen, and Twenty: 

JURY INSTRUCTION NO. 36 . . . [The government] 

charge[s] various instances of knowingly and unlawfully 

dispensing and/or distributing Oxycodone while acting and 

intending to act outside the usual course of professional 

practice and without a legitimate medical purpose, in violation 

of 21 U.S.C. Section 841(a)(1) . . . . In pertinent part, 

Section 841(a) states it is “unlawful for any person knowingly 

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or intentionally to . . . distribute or dispense . . . a controlled 

substance,” unless a specific exception authorizes it. 

JURY INSTRUCTION NO. 37 . . . . To prove Defendant 

Shakeel Kahn is guilty of one or more of these Counts, the 

Government must prove beyond a reasonable doubt each of the 

following elements: . . . (3) Defendant Shakeel Kahn 

knowingly or intentionally distributed or dispensed the 

controlled substance outside the usual course of professional 

medical practice or without a legitimate medical purpose. 

JURY INSTRUCTION NO. 39 . . . The good faith of 

Defendant Shakeel A. Kahn is a complete defense to the 

charges in Count One (conspiracy to commit a federal drug 

crime) as well as the charges in Counts Four, Six, Seven, 

Eleven, Fourteen, Sixteen, Nineteen, and Twenty (knowingly 

and unlawfully dispensing and/or distributing Oxycodone 

outside the usual course of professional practice and without a 

legitimate medical purpose), because good faith on the part of 

Defendant Shakeel Kahn would be inconsistent with 

knowingly and intentionally distributing and/or dispensing 

controlled substances outside the usual course of professional 

practice and without a legitimate medical purpose, which is an 

essential part of the charges. “Good faith” connotes an attempt 

to act in accordance with what a reasonable physician should 

believe to be proper medical practice . . . . The good faith 

defense requires the jury to determine whether Defendant 

Shakeel Kahn acted in an honest effort to prescribe for patients’ 

medical conditions in accordance with generally recognized 

and accepted standards of practice. 

Aplt. App., Vol. I at 236–37, 239.2

Dr. Kahn and Nabeel objected to the district court’s jury instructions regarding 

their potential criminal liability under § 841(a)(1), their respective “good faith” defenses, 

2

 We discuss the jury instructions regarding the remaining counts in Section II.D, 

infra. 

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and the intent requirement under the CSA. The district court overruled these objections. 

The jury returned a verdict of guilty on all counts, except that it acquitted Nabeel of 

causing the death of one of Dr. Kahn’s patients. 

C. Appeals 

Dr. Kahn and Nabeel appealed their convictions on multiple grounds, including 

the jury instructions, and this court affirmed the convictions. See United States v. Kahn, 

989 F.3d 806 (10th Cir.), cert. granted sub nom. Kahn v. United States, and vacated and 

remanded sub nom. Ruan, 142 S. Ct. 2370. Dr. Kahn then appealed to the Supreme 

Court, challenging the jury instructions as they relate to his CSA convictions. 

Specifically, Dr. Kahn argued that the jury instructions did not properly instruct the jury 

regarding the mens rea requirements of the CSA for distributing controlled substances not 

“as authorized.” See 21 U.S.C. § 841(a). 

The Supreme Court determined that this court applied an incorrect scienter 

standard, and it vacated our earlier judgment. Ruan, 142 S. Ct. at 2382. The Supreme 

Court instructed us to address on remand whether the jury instructions that were given at 

Dr. Kahn’s trial complied with the mens rea standard set forth in Ruan, as well as 

whether any instructional error was harmless. Id.

II. DISCUSSION

In order to determine whether the instructions provided to the jury during Dr. 

Kahn’s trial complied with the mens rea standard set forth in Ruan, as well as whether 

any instructional error was harmless beyond a reasonable doubt, we first discuss the CSA 

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and the Ruan decision. Then, applying the scienter requirement discussed in Ruan to the 

jury instructions at issue, we conclude that (1) the district court did not properly instruct 

the jury as to the mens rea that the government was required to prove beyond a 

reasonable doubt to convict Dr. Kahn, and (2) such error was not harmless. 

A. The CSA and Ruan 

Dr. Kahn was convicted by a jury for violating the following provision of the 

CSA: 

(a) Unlawful acts 

Except as authorized by this subchapter, it shall be 

unlawful for any person knowingly or intentionally— 

(1) to manufacture, distribute, or dispense, or possess 

with intent to manufacture, distribute, or dispense, a 

controlled substance; or 

(2) to create, distribute, or dispense, or possess with 

intent to distribute or dispense, a counterfeit substance. 

21 U.S.C. § 841(a) (emphasis added). A federal regulation provides that, to be 

“authorized,” “[a] prescription for a controlled substance . . . must be issued for a 

legitimate medical purpose by an individual practitioner acting in the usual course of his 

professional practice.” 21 C.F.R. § 1306.04. 

In Ruan, the issue before the Supreme Court “concern[ed] the state of mind that 

the Government must prove to convict [a defendant] of violating [§ 841(a)].” Ruan, 142 

S. Ct. at 2375. In resolving this issue, the Supreme Court “h[e]ld that [§ 841(a)]’s 

‘knowingly or intentionally’ mens rea applies to authorization.” Id. Thus, “once a 

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defendant meets the burden of producing evidence that his or her conduct was 

‘authorized,’ the Government must prove beyond a reasonable doubt that the defendant 

knowingly or intentionally acted in an unauthorized manner.” Id. at 2376. 

The Supreme Court rejected the government’s argument that, “once a defendant 

meets his or her burden of production, the Government can convict by proving beyond a 

reasonable doubt that [the defendant] did not even make an objectively reasonable 

attempt to ascertain and act within the bounds of professional medicine.” Id. at 2381 

(internal quotation marks and citation omitted). The Court emphasized that § 841(a) does 

not contain a “good faith,” “objective,” “reasonable,” or “honest effort” standard, and 

courts cannot read such a standard into the statute. Id. The government must prove that a 

“defendant knew or intended that his or her conduct was unauthorized”—it cannot rely 

on comparison to the good faith efforts or mental state of “a hypothetical ‘reasonable’ 

doctor.” Id. at 2381–82. 

Further, the Supreme Court ruled that, to establish mens rea, it is insufficient for 

the government to prove that a defendant acted without “a legitimate medical purpose” or 

outside the “usual course” of generally recognized “professional practice.” Ruan, 142 S. 

Ct. at 2382; see 21 C.F.R. § 1306.04. Proof that a defendant did so is “circumstantial 

evidence” that may be used to prove knowledge of a lack of authorization. Ruan, 142 S. 

Ct. at 2382. Certainly, “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 carried its burden of proving knowledge.” 

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Id. (internal quotation marks and citation omitted). But, in order to convict a defendant, 

the government must prove that the defendant “knew or intended that his or her conduct 

was unauthorized.” Id.; see also United States v. Fabode, No. 21-1491, 2022 WL 

16825408, at *6 (6th Cir. Nov. 8, 2022) (“The Supreme Court reiterated, however, that 

circumstantial evidence and objective criteria such as ‘legitimate medical purpose’ and 

‘usual course’ of ‘professional practice’ are often probative indicia of a defendant’s 

subjective knowledge and intent.” (internal quotation marks and citation omitted)). 

To illustrate its holding, the Supreme Court discussed Liparota v. United States, 

471 U.S. 419 (1985), which concerned the mens rea required to convict a person for the 

unauthorized use of food stamps: 

Analogous precedent reinforces our conclusion. In Liparota, 

we interpreted a statute penalizing anyone who “‘knowingly 

uses [food stamps] in any manner not authorized by’” statute. 

We held that “knowingly” modified both the “use” of food 

stamps element and the element that the use be “not 

authorized.” We applied “knowingly” to the authorization 

language even though Congress had not “explicitly and 

unambiguously” indicated that it should so apply. But if 

knowingly did not modify the fact of nonauthorization, we 

explained, the statute “would . . . criminalize a broad range of 

apparently innocent conduct.” 

Ruan, 142 S. Ct. at 2378 (internal citations omitted). Just as in Liparota, to convict under 

§ 841(a) of the CSA, “the Government may prove by reference to facts and 

circumstances surrounding the case that petitioner knew that his conduct was 

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unauthorized or illegal.” Liparota, 471 U.S. at 434.3

 However, the government’s showing 

of objective criteria, without proving that a defendant actually intended or knew that he 

or she was acting in an unauthorized way, is not enough to convict. Id. 

B. The District Court Incorrectly Instructed the Jury as to Mens Rea 

We conclude that the jury instructions issued in Dr. Kahn’s case are inconsistent 

with the mens rea standard articulated in Ruan, as they do not require the government to 

prove beyond a reasonable doubt that Dr. Kahn knowingly or intentionally acted in an 

unauthorized manner. 

1. Standard 

“We review de novo whether jury instructions, as a whole, correctly state the law 

and provide the jury with an understanding of the issues.” United States v. Little, 829 

F.3d 1177, 1181 (10th Cir. 2016) (citation omitted). “We will disturb a judgment only if 

we have ‘substantial doubt that the jury was fairly guided.’” Id. (quoting United States v. 

Smith, 13 F.3d 1421, 1424 (10th Cir. 1994)). 

3

 While the defendant in Liparota knew that he was purchasing food stamps below 

the market rate, 471 U.S. at 421–22, such knowledge was not enough to establish guilt, 

id. at 429–30. The Supreme Court held that knowingly engaging in conduct that is, in 

fact, unauthorized is not sufficient, even if one is aware of all the factors that render it 

unauthorized. Instead, the government was required to prove that the defendant actually 

knew that his conduct was unauthorized under the law. Importantly, however, the 

Supreme Court concluded that “the Government need not show that [a defendant] had 

knowledge of specific regulations governing food stamp acquisition or possession.” Id. at 

434. 

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2. Analysis 

a. Legitimate Medical Purpose or Usual Course of Professional 

Practice 

The jury was repeatedly instructed that it could convict Dr. Kahn if it concluded 

that he acted outside the usual course of professional medical practice or without a 

legitimate medical purpose. See, e.g., Aplt. App., Vol. I at 220–21 (instructions for Count 

One), 224–25 (instructions for Count One), 232 (instructions for Count One), 236–37 

(instructions for Counts Four, Six, Seven, Eleven, Fourteen, Sixteen, Nineteen, and 

Twenty), 239 (instructions for Counts One, Four, Six, Seven, Eleven, Fourteen, Sixteen, 

Nineteen, and Twenty), 264 (instructions for Count Twenty One). In review of the 

instructions given, we previously concluded that “§ 841(a)(1) and § 1306.04(a) require 

the government to prove that a practitioner-defendant either: (1) subjectively knew a 

prescription was issued not for a legitimate medical purpose; or (2) issued a prescription 

that was objectively not in the usual course of professional practice.” Kahn, 989 F.3d at 

825 (emphasis added) (citing United States v. Nelson, 383 F.3d 1227, 1233 (10th Cir. 

2004)). In partitioning § 1306.04(a), we treated the inquiry under the first “prong” as 

wholly subjective, considering “why a defendant-practitioner subjectively issued that 

prescription, regardless of whether other practitioners would have done the same,” and 

we treated the inquiry under the second prong as wholly objective, considering “whether 

a defendant-practitioner objectively acted within that scope, regardless of whether he 

believed he was doing so.” Id. For two reasons, this analysis is incorrect under Ruan. 

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First, Ruan expressly disallows conviction under § 841(a)(1) for behavior that is 

only objectively unauthorized. The government must prove that a defendant “knowingly 

or intentionally acted in an unauthorized manner.” Ruan, 142 S. Ct. at 2376. 

Second, Ruan treats the two criteria in § 1306.04(a) not as distinct bases to support 

a conviction, but as “reference to objective criteria” that may serve as circumstantial 

evidence of a defendant’s subjective intent to act in an unauthorized manner. Id. at 2382; 

see also id. at 2377 (“[T]he regulatory language defining an authorized prescription is . . . 

ambiguous, written in generalit[ies], susceptible to more precise definition and open to 

varying constructions.” (internal quotation marks and citations omitted)). Under 

§ 841(a)(1), the government always has the burden of “proving that a defendant knew or 

intended that his or her conduct was unauthorized.” Id. at 2382.4

 Accordingly, the jury 

instructions were erroneous because they allowed the jury to convict Dr. Kahn after 

concluding either that Dr. Kahn subjectively knew a prescription was issued not for a 

legitimate medical purpose, or that he issued a prescription that was objectively not in the 

usual course of professional practice. Both approaches run counter to Ruan. 

4

 This court previously stated its concern that “[i]f a subjective standard applied to 

both prongs, a pharmacist who willingly ignored evidence that a prescription was invalid 

could escape liability, so long as he (even unreasonably) believed the prescription was 

filled for a legitimate medical purpose, and he acted within his own (unreasonable) scope 

of professional practice.” Kahn, 989 F.3d at 825. The Supreme Court, however, did not 

share this concern, and Ruan holds that an unreasonable pharmacist may not be convicted 

if he did not intend to act in an unauthorized way. Ruan, 142 S. Ct. at 2382. Of course, 

evidence of objective unreasonableness may support a jury’s ultimate finding that a 

defendant subjectively intended to act without authorization. Id. 

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b. Good Faith Instruction 

The district court provided the jury with the following “good faith” instruction: 

JURY INSTRUCTION NO. 39 . . . The good faith of 

Defendant Shakeel A. Kahn is a complete defense to the 

charges in Count One (conspiracy to commit a federal drug 

crime) as well as the charges in Counts Four, Six, Seven, 

Eleven, Fourteen, Sixteen, Nineteen, and Twenty (knowingly 

and unlawfully dispensing and/or distributing Oxycodone 

outside the usual course of professional practice and without a 

legitimate medical purpose), because good faith on the part of 

Defendant Shakeel Kahn would be inconsistent with 

knowingly and intentionally distributing and/or dispensing 

controlled substances outside the usual course of professional 

practice and without a legitimate medical purpose, which is an 

essential part of the charges. “Good faith” connotes an attempt 

to act in accordance with what a reasonable physician should 

believe to be proper medical practice . . . . The good faith 

defense requires the jury to determine whether Defendant 

Shakeel Kahn acted in an honest effort to prescribe for patients’ 

medical conditions in accordance with generally recognized 

and accepted standards of practice. 

Aplt. App., Vol. I at 239. In light of Ruan, this good faith exception is also problematic. 

The good faith exception’s reliance on terms like “reasonable physician” and 

“should believe” impose an objective standard and are exactly the type of language that 

the Supreme Court stated is impermissible. Ruan, 142 S. Ct. at 2381 (“The Government’s 

[‘objectively reasonable good-faith effort’] standard would turn a defendant’s criminal 

liability on the mental state of a hypothetical ‘reasonable’ doctor, not on the mental state 

of the defendant himself or herself.”). Section 841(a) does not “use[] words such as ‘good 

faith,’ ‘objectively,’ ‘reasonable,’ or ‘honest effort,’” and a district court cannot insert 

them into the jury instructions. Id. Further, the instruction’s use of the word “attempt” is 

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equally precarious. The question to be posed to a jury is whether a physician was 

subjectively intending to act in a way that he believed was unauthorized—not whether he 

was attempting to act in a way that a “reasonable physician should believe” was 

authorized or unauthorized. See Aplt. App., Vol. I at 239. Again, “[t]he Government . . . 

[must] prove knowledge of a lack of authorization.” Ruan, 142 S. Ct. at 2382. 

3. Conclusion 

To convict under the CSA, “the Government must prove beyond a reasonable 

doubt that the defendant knowingly or intentionally acted in an unauthorized manner.” Id.

Here, the instructions provided to the jury improperly interjected a good faith exception 

and effectively lowered the government’s burden to showing only that Dr. Kahn’s 

behavior was objectively unauthorized—not that Dr. Kahn intended to act without 

authorization. The government argued in Ruan that the Supreme Court “should read 

[§ 841] as implicitly containing an ‘objectively reasonable good-faith effort’ or ‘objective 

honest-effort standard,’” but the Supreme Court was “not convinced.” Id. at 2381. So our 

analysis, likewise, must end there. The instructions given in Dr. Kahn’s trial do not 

correctly state the mens rea requirement of § 841(a)(1), as articulated in Ruan. 

C. The Invalid Jury Instructions Did Not Result in Harmless Error 

Next, we must determine whether the errors in the jury instructions are harmless 

beyond a reasonable doubt. Because the issue of Dr. Kahn’s intent was contested during 

trial, and because the government has not established beyond a reasonable doubt that the 

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jury determined that Dr. Kahn knowingly or intentionally acted not “as authorized,” we 

conclude that the instructions provided to the jury did not result in harmless error. 

1. Standard 

The purpose of jury instructions is to give jurors the correct principles of law 

applicable to the facts so that they can reach a correct conclusion as to each element of an 

offense according to the law and the evidence. However, “[e]ven when the district court 

fails to include an element of the crime in the instruction (including a mens rea element), 

we . . . apply the harmless error rule, asking whether it appears beyond a reasonable 

doubt that the error complained of did not contribute to the verdict obtained.” Little, 829 

F.3d at 1183 (quoting United States v. Sorensen, 801 F.3d 1217, 1229 (10th Cir. 2015)). 

The harmless error rule also applies where an instruction was given incorrectly. See, e.g., 

United States v. Benvie, 18 F.4th 665, 670 (10th Cir. 2021). When applying the harmless 

error rule, “we must determine ‘whether the guilty verdict actually rendered in this trial 

was surely unattributable to the [alleged] error,’” United States v. Mullikin, 758 F.3d 

1209, 1211 (10th Cir. 2014) (quoting Sullivan v. Louisiana, 508 U.S. 275, 279 (1993))—

not “whether, in a trial that occurred without the error, a guilty verdict would surely have 

been rendered,” Sullivan, 508 U.S. at 279. “That must be so, because to hypothesize a 

guilty verdict that was never in fact rendered—no matter how inescapable the findings to 

support that verdict might be—would violate the jury-trial guarantee.” Id.

“It is well-established that the burden of proving harmless error is on the 

government.” United States v. Holly, 488 F.3d 1298, 1307 (10th Cir. 2007). Again, the 

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general test for harmless error requires that the government prove “beyond a reasonable 

doubt that the error complained of did not contribute to the verdict obtained.” United 

States v. Luke-Sanchez, 483 F.3d 703, 705 (10th Cir. 2007) (citing Neder, 527 U.S. at 15) 

(applying this test to “[a] jury instruction that improperly describe[d] an element of the 

charged crime”); see also Neder, 527 U.S. at 11 (extending harmless error analysis to 

instructions that omit an element; “[o]mitting an element can easily be analogized to 

improperly instructing the jury on the element, an error that is subject to harmless-error 

analysis.”). In the context of jury instructions that omit—rather than misstate—an 

element, we have sometimes invoked a passage of Neder that imposes additional 

requirements. Under that test, the government must prove “beyond a reasonable doubt 

that the omitted element was uncontested and supported by overwhelming evidence, such 

that the jury verdict would have been the same absent the error.” Neder, 527 U.S. at 11. 

We have previously declined to “parse out the proper formulation of the harmless-error 

standard for direct review under Neder,” United States v. Schneider, 665 F. App’x 668, 

672 (10th Cir. 2016),5

 and we may continue to avoid doing so here. Under either iteration 

5

 “Defendants contend the applicable standard for determining harmless error 

when, as here, the jury was not instructed on an element of the offense is whether the 

‘reviewing court concludes beyond a reasonable doubt that the omitted element was 

uncontested and supported by overwhelming evidence, such that the jury verdict would 

have been the same absent the error.’ Neder, 527 U.S. at 17. In reviewing such 

instructional error for harmlessness on direct appeal from a conviction, we have 

sometimes invoked this standard verbatim. We have on other occasions invoked another 

passage from Neder that does not refer to whether the omitted element was uncontested 

or supported by overwhelming evidence, but simply asks more generally ‘whether it 

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of the test for harmless error, the government has not shown beyond a reasonable doubt 

that the instructional error was harmless. 

2. Analysis 

During his testimony at trial, Dr. Kahn did not contest the fact that he wrote the 

relevant prescriptions, nor did he contest that the testifying patients were abusing or 

selling their medications. The central issue put to the jury in Dr. Kahn’s trial was his 

intent in issuing the charged prescriptions. We start with Neder’s test for reviewing 

instructions that omit an element, moving then to the general harmless error test. We 

conclude that, under both tests, the government has not met its burden in showing that the 

erroneous jury instructions played no part in the jury’s verdict. 

a. The Mens Rea Element Was Not Uncontested and Supported by 

Overwhelming Evidence, Such That the Jury Verdict Would Have 

Been the Same Absent the Error 

Under the more specific test articulated in Neder for reviewing instructions which 

omitted elements, the government must prove “beyond a reasonable doubt that the 

omitted element was uncontested and supported by overwhelming evidence, such that the 

jury verdict would have been the same absent the error.” 527 U.S. at 11. Here, the 

government is correct that the Supreme Court has acknowledged that “the scope of a 

doctor’s prescribing authority” remains tethered “to objective criteria such as ‘legitimate 

appears beyond a reasonable doubt that the error complained of did not contribute to the 

verdict obtained.” Schneider, 665 F. App’x at 672 (internal citations omitted). 

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medical purpose’ and ‘usual course’ of ‘professional practice.’” Ruan, 142 S. Ct. at 2382. 

A physician’s serial disregard of accepted medical norms constitutes relevant evidence of 

his mental state, and “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 carried its burden of proving knowledge.” 

Id. (internal quotation marks and citations omitted). But, while the government may point 

to voluminous trial testimony and numerous exhibits meant to prove (through 

circumstantial evidence) that Dr. Kahn knowingly or intentionally acted in an 

unauthorized manner, we cannot reach this conclusion. 

This is not a case in which the element of the crime that was impacted6

 by the 

invalid jury instruction was “uncontested and supported by overwhelming evidence,” and 

where “the defendant ‘did not contest the element . . . at trial,’ and did not ‘suggest that 

he would introduce any evidence bearing upon the issue . . . if so allowed.’” United States 

v. Ellis, 868 F.3d 1155, 1172 (10th Cir. 2017) (quoting Neder, 527 U.S. at 15, 17). Where 

an element of an offense is contested at trial, as it was here, the Constitution requires that 

the issue be put before a jury—not an appellate court. See Neder, 527 U.S. at 18–19 

(discussing the Sixth Amendment’s jury guarantee; “[i]n a case . . . where a defendant did 

not, and apparently could not, bring forth facts contesting the omitted element, answering 

6

 We need not decide whether the mens rea element was omitted or rather 

misstated in the jury instructions. Regardless of the label one could apply, the 

instructional requirements of Ruan are not satisfied. 

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the question whether the jury verdict would have been the same absent the error does not 

fundamentally undermine the purposes of the jury trial guarantee”). In this case, 

Dr. Kahn’s intent was in dispute throughout his trial and was the centerpiece of his 

defense. A jury, properly instructed, must address whether the government carried its 

burden to establish Dr. Kahn’s intent beyond a reasonable doubt. 

For this court to now essentially retry the case on appeal and opine on what verdict 

the jury would have reached if it had been properly instructed asks too much of an 

appellate court. This is particularly true here, where we would be determining Dr. Kahn’s 

subjective intent on a cold record. This court will not wade into the evidence to now 

apply the correct instructions—that is the jury’s prerogative. 

b. The Guilty Verdict Actually Rendered in Dr. Kahn’s Trial Was Not 

Surely Unattributable to the Alleged Instructional Error 

The more general harmless error question is whether, given what the jury 

necessarily did find based on the instructions it was provided, “the guilty verdict actually 

rendered in this trial was surely unattributable to the [alleged] error.” Mullikin, 758 F.3d 

at 1211 (quoting Sullivan, 508 U.S. at 279). Here, we cannot say with certainty that the 

erroneous instructions, which effectively reduced the government’s burden of proof, did 

not contribute to the verdict. 

As we stated in our prior opinion, the jury instructions given in Dr. Kahn’s trial 

meant that the jury “could only convict Dr. Kahn if it found, beyond a reasonable doubt, 

that Dr. Kahn failed to even attempt or make some honest effort to apply the appropriate 

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standard of care.” Kahn, 989 F.3d at 826. The instructions provided in Dr. Kahn’s trial 

did not require the jury to decide whether Dr. Kahn knowingly or intentionally acted 

without authorization. 

While proof that Dr. Kahn failed to try to conform his prescribing practices to the 

standards of his profession may “go far to show, circumstantially at least, that [Dr. Kahn] 

actually knew he was acting outside the standards of his profession,” Aple. Supp. Br. at 6, 

that evidence does not fully satisfy the requirement that the government prove that 

Dr. Kahn “knowingly or intentionally acted in an unauthorized manner,” Ruan, 142 S. Ct. 

at 2376. It is not enough that the jury found that Dr. Kahn failed to attempt or make some 

honest effort to apply the appropriate standard of care, nor is it enough that the jury 

accepted that Dr. Kahn subjectively knew a prescription was issued not for a legitimate 

medical purpose, and/or issued a prescription that was objectively not in the usual course 

of professional practice. 

To allow conviction where the government proved only that Dr. Kahn failed to 

attempt or make some honest effort to apply the appropriate standard of care does not 

require any finding by the jury that Dr. Kahn intended to act not “as authorized.” The 

government must show that the jury necessarily made a finding that Dr. Kahn knowingly 

or intentionally acted not “as authorized.” As it stands, the jury in Dr. Kahn’s case was 

provided incorrect instructions, and that error went directly to the heart of the trial: 

Dr. Kahn’s intent. The instructions allowed conviction if the jury concluded “that 

Dr. Kahn failed to even attempt or make some honest effort to apply the appropriate 

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standard of care.” Kahn, 989 F.3d at 826. Based on the jury instructions, as they were 

written and presented to the jury, the jury was not required to find that Dr. Kahn intended 

to or knowingly did act not “as authorized.” The jury did not make the required mens rea 

finding, and “to hypothesize a guilty verdict that was never in fact rendered—no matter 

how inescapable the findings to support that verdict might be—would violate the jurytrial guarantee.” Sullivan, 508 U.S. at 279. 

3. Conclusion 

We cannot conclude beyond a reasonable doubt that the mens rea element, “was 

uncontested and supported by overwhelming evidence, such that the jury verdict would 

have been the same absent the error.” Neder, 527 U.S. at 17 (emphasis added). Nor can 

we conclude that the jury’s verdict was unattributable to the erroneous instruction. The 

government may be able to present circumstantial evidence that Dr. Kahn knowingly or 

intentionally acted in an unauthorized manner (indeed, the government has attempted to 

do so on remand to this court), but this court should not assume the responsibility of 

making a finding on a contested issue of fact. Connecticut v. Johnson, 460 U.S. 73, 85–

86 (1983) (“If the jury may have failed to consider evidence of intent, a reviewing court 

cannot hold that the error did not contribute to the verdict. The fact that the reviewing 

court may view the evidence of intent as overwhelming is then simply irrelevant.”); see 

also United States v. Twitty, 641 F. App’x 801, 805 (10th Cir. 2016) (“Appellate judges 

are poorly equipped to evaluate states of mind based on a cold record. The issue of . . . 

subjective intent is one best left to the determination of a properly instructed jury.” 

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(internal quotation marks and citations omitted)). We cannot act as a “second jury.” 

Neder, 527 U.S. at 19 (citation omitted). We conclude that the erroneous jury instructions 

issued in Dr. Kahn’s trial did not result in harmless error. 

D. Dr. Kahn’s Remaining Convictions 

Finally, we discuss which of the counts of conviction, specifically, were affected 

by erroneous instructions. We determine that each of Dr. Kahn’s convictions was 

impacted by erroneous instructions in a way that prejudiced him, and, therefore, we 

remand with directions to vacate his convictions on all counts. 

The jury instructions pertaining 21 U.S.C. §§ 841(a)(1) and (b)(1)(C), as charged 

in Counts Four, Six, Seven, Eleven, Fourteen, Sixteen, Nineteen, and Twenty all contain 

the following language: 

 To Prove [Dr. Kahn] is guilty of [these counts], the 

Government must prove beyond a reasonable doubt [that] . . . 

[Dr. Kahn] knowingly or intentionally distributed or dispensed 

the controlled substance outside the usual course of 

professional medical practice or without a legitimate medical 

purpose. 

Aplt. App., Vol. I at 237. The instructions as to these counts and, in addition, Count One, 

which charges conspiracy to dispense and distribute controlled substances resulting in 

death, in violation of 21 U.S.C. §§ 846, 841(a)(1), (b)(1)(C), and (b)(2), also include the 

good faith exception. Id. at 239–40. Accordingly, as discussed above, the instructions as 

to Counts One, Four, Six, Seven, Eleven, Fourteen, Sixteen, Nineteen, and Twenty are 

erroneous and did not result in harmless error. 

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 As for the remaining counts, the instructions predicate conviction on the jury’s 

finding of guilt in the erroneously-instructed Counts One, Four, Six, Seven, Eleven, 

Fourteen, Sixteen, Nineteen, and Twenty. For example, the instructions for Counts Five, 

Nine, and Ten, which charge Dr. Kahn with aiding and abetting his codefendant in 

furtherance of § 841(a)(1) crimes, in violation of 21 U.S.C. §§ 841(a)(1) and (b)(1)(C) 

and 18 U.S.C. § 2, state, “[t]his means the government must prove that [Dr. Kahn] shared 

[his codefendant’s] knowledge of the underlying [§ 841(a)(1)] criminal act and intended 

to help him.” Id. at 258. The instructions for Counts Eight, Twelve, Thirteen, Seventeen, 

and Eighteen charge Dr. Kahn with use of a communication facility in furtherance of the 

crimes charged in Counts One, Seven, and Eleven, in violation of 21 U.S.C. § 843(b). Id.

at 253–55. Count Two charges Dr. Kahn with possession of a firearm, again, “in 

furtherance of a federal drug trafficking crime,” in violation of 18 U.S.C. § 924(c)(1), and 

the instructions indicate that conviction rested on whether the jury concluded that Dr. 

Kahn possessed a firearm in furtherance of Count One. Id. at 242–43. The instructions for 

Count Twenty One charge Dr. Kahn with “continuing criminal enterprise,” in violation of 

21 U.S.C. § 848(a), (b), and (c), which the instructions define as the continuation of the 

illegal drug activities detailed in Counts One through Twenty. Id. at 262. Finally, the 

instructions for Counts Twenty Two and Twenty Three charge Dr. Kahn with engaging in 

monetary transactions derived from specified unlawful activity (money laundering), in 

violation of 18 U.S.C. § 1957—the “unlawful activity” at issue is, again, tied back to the 

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conduct charged in Counts One, Four through Seven, Nine through Eleven, Fourteen, 

Sixteen, Nineteen, and Twenty. Id. at 271–73. 

For each § 841(a)(1) charge on which Dr. Kahn was convicted, the instructions 

erroneously articulated the mens rea requirement in light of Ruan. As regards the 

remaining charges, the instructions pertaining to those charges are likewise predicated, at 

least in part, on one or more of the erroneous § 841(a)(1) instructions. Accordingly, we 

conclude that Dr. Kahn’s convictions as to each count must be vacated. 

III. CONCLUSION 

The jury instructions issued in Dr. Kahn’s trial incorrectly instructed the jury 

regarding the mens rea requirement of § 841(a), and this same error infected the 

instructions given on all counts. The government has not shown beyond a reasonable 

doubt that the erroneous jury instructions resulted in harmless error. Accordingly, we 

VACATE Dr. Kahn’s convictions and REMAND for new trial. 

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