United States v. Castro Alavez

FOR PUBLICATION

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA, No. 24-1921

D.C. No.

Plaintiff - Appellee,

1:23-cr-00055-

SOM-1

v.

LUIS MIGUEL CASTRO ALAVEZ,

OPINION

Defendant - Appellant.

Appeal from the United States District Court

for the District of Hawaii

Susan O. Mollway, District Judge, Presiding

Argued and Submitted June 3, 2025

Honolulu, Hawaii

Filed February 20, 2026

Before: William A. Fletcher, Morgan B. Christen, and

Roopali H. Desai, Circuit Judges.

Opinion by Judge Desai

2 USA V. CASTRO ALAVEZ

SUMMARY *

Criminal Law

The panel affirmed in part and vacated in part the district

court’s judgment, and remanded, in a case in which a jury

found Luis Miguel Castro Alavez guilty of one count of

attempted possession with intent to distribute 500 grams of

a mixture containing methamphetamine and one count of

conspiracy to possess 500 grams of a mixture containing

methamphetamine.

Castro Alavez argued that his conviction and sentence

for attempted possession of a specific drug type and quantity

should be reversed under United States v. Hunt, 656 F.3d

906 (9th Cir. 2011), because the district court improperly

instructed the jury that “the government does not have to

prove that [Castro Alavez] knew that the controlled

substance was methamphetamine or knew the quantity of

methamphetamine.” The panel agreed in part. To impose the

heightened penalty prescribed by 21 U.S.C.

§ 841(b)(1)(A)(viii), the government must prove that Castro

Alavez intended to possess 500 grams of a

methamphetamine mixture. On the facts of this case, the

district court’s erroneous jury instruction was not harmless.

The panel declined to extend to the attempt context a line of

conspiracy cases that require no heightened mens rea beyond

what the underlying crime requires. The panel therefore

vacated Castro Alavez’s sentence for attempted possession

of a controlled substance, but not his conviction.

*

This summary constitutes no part of the opinion of the court. It has

been prepared by court staff for the convenience of the reader.

USA V. CASTRO ALAVEZ 3

Castro Alavez also argued that his attempt conviction

and conspiracy conviction should be vacated because the

district court improperly admitted religious images and

expert testimony about “narco saints.” While the expert

testimony did not satisfy Federal Rule of Evidence 702, the

panel held that the district court’s error in admitting this

evidence was harmless. The panel thus affirmed Castro

Alavez’s convictions.

COUNSEL

Michael F. Albanese (argued), Sara Ayabe, and Gregg P.

Yates, Assistant United States Attorneys; Clare E. Connors,

United States Attorney; Office of the United States Attorney,

United States Department of Justice, Honolulu, Hawaii; for

Plaintiff-Appellee.

Georgia K. McMillen (argued), Law Office of Georgia K.

McMillen, Wailuku Maui, Hawaii, for Defendant-Appellant.

4 USA V. CASTRO ALAVEZ

OPINION

DESAI, Circuit Judge:

A jury found Luis Miguel Castro Alavez (“Castro

Alavez”) guilty of one count of attempted possession with

intent to distribute 500 grams of a mixture containing

methamphetamine and one count of conspiracy to possess

500 grams of a mixture containing methamphetamine, both

in violation of 21 U.S.C. §§ 846, 841(a)(1),

841(b)(1)(A)(viii). Castro Alavez appeals on two grounds.

First, he argues that his conviction and sentence for

attempted possession of a specific drug type and quantity

should be reversed under United States v. Hunt, 656 F.3d

906 (9th Cir. 2011), because the district court improperly

instructed the jury that “the government does not have to

prove that [Castro Alavez] knew that the controlled

substance was methamphetamine or knew the quantity of

methamphetamine.” We agree in part. To impose the

heightened penalty prescribed by § 841(b)(1)(A)(viii), the

government must prove that Castro Alavez intended to

possess 500 grams of a methamphetamine mixture. On the

facts of this case, the district court’s erroneous jury

instruction was not harmless. We therefore vacate Castro

Alavez’s sentence for attempted possession of a controlled

substance, but not his conviction.

Second, Castro Alavez contends that his attempt

conviction and conspiracy conviction should be vacated

because the district court improperly admitted religious

images and expert testimony about “narco saints.” While the

expert testimony did not satisfy Federal Rule of Evidence

702, we nonetheless hold that the district court’s error in

USA V. CASTRO ALAVEZ 5

admitting this evidence was harmless. We thus affirm Castro

Alavez’s convictions.

BACKGROUND

Castro Alavez, a native and citizen of Mexico, entered

the United States in 2017 and lived in California until 2023.

On June 15, 2023, Castro Alavez traveled to Hilo, Hawaii

and rented a studio apartment from Diana Machado. Castro

Alavez’s vacation rental was on the same property as

Machado’s residence.

On June 28, 2023, the postal service delivered a package

addressed to “Marco Alavez” to Machado’s residence.

Machado did not recognize the name on the package and

became suspicious of its contents. Shortly after, Castro

Alavez went to Machado’s residence, presumably to look for

the package. When Machado opened the door, Castro Alavez

saw the package sitting on her table and pointed at it saying,

“Mine, mine.” Machado responded that the package

belonged to her daughter. Castro Alavez left briefly but

returned with tracking information indicating that he was

expecting a package and asked whether she received it.

Machado told him that she did not receive his package but

would let him know if she did.

After he left, Machado opened the package and

discovered a substance that felt like “rock salt.” Suspecting

that the substance could be drugs, Machado took the package

to the police station and gave it to Special Agent Ryan

Faulkner (“Agent Faulkner”) of Homeland Security

Investigations. Agent Faulkner obtained a search warrant

and tested the package for narcotics, which revealed

4,970.92 grams of a mixture or substance containing a

detectable amount of methamphetamine.

6 USA V. CASTRO ALAVEZ

Police arrested Castro Alavez, and Agent Faulkner

interviewed him at the police station. In the interview, Castro

Alavez explained that he was hired by an unknown man at a

nightclub in Riverside, California, who claimed he could

help Castro Alavez get out of poverty if Castro Alavez

agreed to pick up an unspecified item and give it to another

individual. The job also required Castro Alavez to deposit

money into a designated bank account. The man assured

Castro Alavez that he would not be doing anything wrong

but warned that, if Castro Alavez agreed to the work, there

would be “no going back” and that if Castro Alavez pulled

“a fast one,” Castro Alavez and his family would be in

danger.

Castro Alavez accepted the job and was sent to Hawaii.

There, an unknown man gave Castro Alavez $8,000 to

$10,000 and instructed him to wire the money to a bank

account in Mexico. Castro Alavez told Agent Faulkner that

he knew the money was drug money but felt that he was in

too deep.

Castro Alavez moved into Machado’s vacation rental in

Hawaii and gave Machado’s address to the people who

recruited him. Castro Alavez explained to Agent Faulkner

that he was instructed to retrieve a delivery at the vacation

rental and to give it to an individual who would come to pick

it up. The same morning the package arrived at Machado’s

residence, Castro Alavez received a call notifying him that

the package would arrive soon. Castro Alavez stated in his

interview that he knew the package likely contained drugs

but did not know the type or quantity of drugs inside.

Castro Alavez also consented to a search of his two cell

phones, his shoulder bag, and the vacation rental. And he

shared with Agent Faulkner the location of receipts for

USA V. CASTRO ALAVEZ 7

several wire transfers to Mexico, which investigators found

during their search of the vacation rental.

Officers also found messages on Castro Alavez’s cell

phones instructing him to wire large amounts of U.S.

currency to Mexico and to conceal money inside chocolate

boxes before sending the boxes through the postal service.

In addition, they discovered two drawings from Castro

Alavez’s shoulder bag, depicting Jesus Malverde and Santa

Muerte, Mexican patron saints. Castro Alavez explained that

the people who recruited him gave him the Jesus Malverde

drawing in California and that the saint “helps the poor.”

The government charged Castro Alavez with:

(1) conspiracy to distribute and possess with intent to

distribute 500 grams of a mixture containing

methamphetamine in violation of 21 U.S.C. §§ 841(a)(1),

841(b)(1)(A)(viii), and 846 (count one); and (2) attempted

possession with intent to distribute 500 grams of a mixture

containing methamphetamine in violation of 21 U.S.C.

§§ 841(a)(1), 841(b)(1)(A)(viii), and 846 (count two). At

trial, the district court gave the following jury instruction for

attempted possession over Castro Alavez’s objection:

If you find the defendant guilty of [attempted

possession of a controlled substance], you are

then to determine whether the government

proved beyond a reasonable doubt that the

controlled substance involved in the offense

was 500 grams or more of a mixture or

substance containing a detectable amount of

methamphetamine, its salts, isomers, and

salts of its isomers. Your determination of

weight must not include the weight of any

8 USA V. CASTRO ALAVEZ

packaging material. Your decision as to type

of drug and weight must be unanimous.

The government does not have to prove that

the defendant knew that the controlled

substance was methamphetamine or knew the

quantity of methamphetamine.

The jury convicted Castro Alavez on both counts. The

district court sentenced him to concurrent 120-month prison

terms on each count, followed by five years of supervised

release. Castro Alavez timely appeals.

STANDARD OF REVIEW

We review “de novo whether the jury instructions

accurately define the elements of a statutory offense.”

United States v. Hicks, 217 F.3d 1038, 1045 (9th Cir. 2000).

While we ordinarily review a district court’s evidentiary

rulings for an abuse of discretion, United States v. Shryock,

342 F.3d 948, 981 (9th Cir. 2003), we review unpreserved

objections for plain error, Tan Lam v. City of Los Banos, 976

F.3d 986, 1006 (9th Cir. 2020).

DISCUSSION

I. The government must prove a defendant’s intent to

possess the specified drug type and quantity to

impose an increased penalty based on the defendant’s

attempted possession of a particular type and

quantity of controlled substance.

21 U.S.C. § 841(a) makes it unlawful for a person to

“knowingly or intentionally” possess with the intent to

distribute a controlled substance. Section 841(b)(1) sets out

separate and increasing penalties depending on the type and

quantity of the controlled substance. Relevant here,

USA V. CASTRO ALAVEZ 9

§ 841(b)(1)(A)(viii) imposes a mandatory minimum

sentence of ten years imprisonment if the offense involves

“500 grams or more of a mixture or substance containing a

detectable amount of methamphetamine.” Section 846

provides that “[a]ny person who attempts or conspires to

commit any offense” under § 841(a) “shall be subject to the

same penalties as those prescribed for the offense.”

The Sixth Amendment and Due Process Clause

“require[] that each element of a crime be proved to the jury

beyond a reasonable doubt.” Alleyne v. United States, 570

U.S. 99, 104 (2013). “[A]ny ‘facts that increase the

prescribed range of penalties to which a criminal defendant

is exposed’”—such as drug type and quantity under

§ 841(b)(1)—constitute “elements of the crime” that the

government must prove to the jury beyond a reasonable

doubt. Id. at 111 (quoting Apprendi v. New Jersey, 530 U.S.

466, 490 (2000)). We applied these principles in Hunt and

held that, to impose a heightened penalty under § 841(b)(1)

based on a defendant’s attempted possession of a particular

type and quantity of controlled substance, the government

must prove that the defendant intended to possess the

specified drug type and quantity. 656 F.3d at 913.

Castro Alavez argues that we must vacate his sentence

under Hunt. We agree.

A. Hunt controls our analysis.

In Hunt, after police intercepted a package and

discovered that it contained about a kilogram of cocaine, the

government charged the defendant with attempted

possession of 500 grams or more of a mixture containing

cocaine. Id. at 908–09. The defendant pleaded guilty without

a plea agreement to attempted possession of a controlled

substance but denied knowing the specific amount or type of

10 USA V. CASTRO ALAVEZ

drug. Id. at 909–10. The district court sentenced him to 15

years in prison for attempting to possess cocaine in violation

of §§ 846 and 841(b)(1)(C), a penalty provision that

increases the statutory maximum sentence from a one-year

term of imprisonment to a 20-year term for offenses

involving specified drugs, including cocaine. Id. at 908,

910–11, 913, 916; compare 21 U.S.C. § 841(b)(1)(C) with

§ 841(b)(3).

We held that because the drug type “support[ed] an

increase in the maximum statutory sentence [the defendant]

faced,” it was an element of the crime the government must

prove beyond a reasonable doubt. Hunt, 656 F.3d at 912–13.

Although the defendant admitted that he intended to possess

a controlled substance, he did not admit to “attempt[ing] to

possess cocaine.” Id. The facts to which the defendant

admitted in his guilty plea were thus insufficient to support

a sentence under § 841(b)(1)(C). Id. at 913. Without “an

explicit admission” or proof of intent, the drug type “could

not be used to support an increase in the maximum statutory

sentence.” Id. at 912–13.

We rejected the government’s contention that it need

only prove the defendant “‘knowingly’ attempted to possess

cocaine.” Id. at 912. “While knowing possession is an

element of the completed offense of possession with intent

to distribute, attempted possession requires proof of intent,

not knowledge.” Id. (citations omitted); see also United

States v. Gracidas-Ulibarry, 231 F.3d at 1188, 1196 (9th Cir.

2000) (en banc) (explaining that “‘purpose’ corresponds to

the concept of specific intent, while ‘knowledge’

corresponds to general intent”). Thus, to obtain a sentence

under § 841(b)(1)(C) for attempted possession of cocaine,

“the government needed to prove that [the defendant]

intended to possess cocaine.” Hunt, 656 F.3d at 912. And

USA V. CASTRO ALAVEZ 11

because the government failed to do so, we vacated the

sentence. Id. at 916–17.

B. Hunt is buttressed by our precedent holding that

criminal attempt requires specific intent even

when the underlying crime does not.

We explored the mens rea required for criminal attempt

in Gracidas-Ulibarry. There, we considered what level of

intent the government must prove to convict a defendant of

attempted illegal reentry under § 1326, when the underlying

offense required a showing only of general intent and the

statute did not otherwise specify an intent requirement. 231

F.3d at 1190.

Our starting point was the common law, which defines

attempt as “the specific intent to engage in criminal conduct

and an overt act which is a substantial step towards

committing the crime.” Id. at 1192 (citation modified). This

“accepted common law definition” underlies our rule that

“Congress’ use of the term ‘attempts’ in a criminal statute

manifest[s] a requirement of specific intent to commit the

crime attempted, even when the statute d[oes] not contain an

explicit intent requirement.” Id. (citing United States v.

Hadley, 918 F.2d 848, 853 (9th Cir. 1990) and United States

v. Sneezer, 900 F.2d 177, 179 (9th Cir. 1990)); see also

Neder v. United States, 527 U.S. 1, 21 (1999) (holding that

when a term has a settled common law meaning, “a court

must infer, unless the statute otherwise dictates, that

Congress means to incorporate the established meaning”

(citation modified)).

By requiring specific intent for attempt crimes, we

“resolve the uncertainty [over] whether the defendant’s

purpose was indeed to engage in criminal, rather than

innocent, conduct.” Gracidas-Ulibarry, 231 F.3d at 1193.

12 USA V. CASTRO ALAVEZ

And such “uncertainty is not present when the defendant has

completed the underlying crime, because the completed act

is itself culpable conduct.” Id. Thus, we held that attempted

illegal reentry requires proof that the noncitizen “had the

purpose, i.e., conscious desire, to reenter the United States

without the express consent of the Attorney General.” Id. at

1196. This is true even though the substantive offense—

illegal reentry—does not require either willfulness or an

unlawful intent. Id. at 1194–95.

Our conclusion in Gracidas-Ulibarry was not

exceptional. Years earlier, we required the government to

prove a higher mens rea for attempt than for substantive

offenses. See, e.g., United States v. Darby, 857 F.2d 623, 626

(9th Cir. 1988) (holding that attempted bank robbery

requires a specific intent to rob a bank, even though bank

robbery is a general intent crime); Sneezer, 900 F.2d at 179

(holding that attempted sexual abuse under 18 U.S.C. § 2242

required a specific intent to commit the crime even though

§ 2242 “itself d[id] not appear to include any element of

specific intent”). And we have continued to require specific

intent for attempt crimes since Gracidas-Ulibarry. See, e.g.,

United States v. Ramirez-Martinez, 273 F.3d 903, 914 (9th

Cir. 2001) (holding that attempted unlawful transportation of

noncitizens requires a “purpose, i.e., the conscious desire, to

transport an undocumented [noncitizen],” even though

“[a]ctual (completed) transporting” requires only that the

defendant act with “reckless disregard” of the noncitizen’s

status (citation modified)), overruled on other grounds by

United States v. Lopez, 484 F.3d 1186 (9th Cir. 2007) (en

banc).

In short, even if a substantive offense lacks an intent

requirement, an attempt to commit that offense requires

specific intent. Hunt applied this longstanding mens rea

USA V. CASTRO ALAVEZ 13

requirement to attempt under § 841(b)(1), and it controls

here. The district court thus erred by instructing the jury that

the government need not prove that Castro Alavez intended

to possess 500 grams or more of a methamphetamine

mixture. This error was not harmless. 1 We thus vacate

Castro Alavez’s sentence for attempted possession of a

controlled substance and remand for resentencing. 2

1

The government does not argue harmlessness and therefore forfeits the

issue. United States v. Rodriguez, 880 F.3d 1151, 1163 (9th Cir. 2018).

But even so, the erroneous instructions relieved the government of its

burden to prove an element of the offense. See Dang v. Cross, 422 F.3d

800, 805 (9th Cir. 2005) (“In evaluating jury instructions, prejudicial

error results when, looking to the instructions as a whole, the substance

of the applicable law was not fairly and correctly covered.” (citation

modified)). And this error likely affected the outcome because there is

scant evidence suggesting Castro Alavez knew the type and quantity of

drugs involved. See id. at 811–12.

2

To the extent Castro Alavez argues that the district court’s instructional

error warrants vacatur of his conviction for attempted possession of a

controlled substance, we disagree. Drug type and quantity are elements

of the “aggravated crime” created by § 841(b)(1)(A)(viii), but they are

not elements of the “core crime” set forth in §§ 841(a) and 846. See

Alleyne, 570 U.S. at 113. The district court properly instructed the jury

on the core crime of attempted possession of a controlled substance, and

the jury found Castro Alavez guilty of this offense. Thus, Castro Alavez

is entitled only to resentencing. See United States v. Toliver, 351 F.3d

423, 431 (9th Cir. 2003) (holding that the government’s failure to prove

drug type and quantity did not entitle the defendants to a judgment of

acquittal and that the district court was instead “restricted in the

maximum sentence that it could impose”), abrogated on other grounds

by Blakely v. Washington, 542 U.S. 296 (2004); see also Alleyne, 570

U.S. at 114–18 (vacating the defendant’s sentence for the aggravated

crime of brandishing a firearm and remanding “for resentencing

consistent with the jury’s verdict” of guilty as to the core crime of using

or carrying a firearm); United States v. Delgado-Marrero, 744 F.3d 167,

192 (1st Cir. 2014) (collecting cases establishing that a defendant with a

14 USA V. CASTRO ALAVEZ

II. We decline to extend our separate line of cases

involving criminal conspiracy to this context.

To avoid Hunt, the government argues that United States

v. Collazo, 984 F.3d 1308 (9th Cir. 2021) (en banc)

overruled it. But Collazo—which addressed the crime of

conspiracy—did not expressly or impliedly overrule Hunt

and, in fact, did not involve the same crime. Still, the

government insists that Collazo controls because its

reasoning is “clearly irreconcilable” with Hunt.

“[W]here the reasoning or theory of our prior circuit

authority is clearly irreconcilable with the reasoning or

theory of intervening higher authority, . . . [we are] bound by

the later and controlling authority, and should reject the prior

circuit opinion as having been effectively overruled.” Miller

v. Gammie, 335 F.3d 889, 893 (9th Cir. 2003) (en banc). But

we remain “bound by our prior precedent if it can be

reasonably harmonized with the intervening [higher]

authority.” Lair v. Bullock, 697 F.3d 1200, 1206 (9th Cir.

2012) (citation modified).

At bottom, Hunt controls here unless the government can

show that Hunt’s reasoning is “clearly irreconcilable” with

Collazo. The government does not meet this “high standard.”

Id. at 1207 (citation modified).

successful Apprendi or Alleyne claim “is not entitled to a new trial, but

rather is only entitled to resentencing”).

USA V. CASTRO ALAVEZ 15

A. Collazo relied on “well-established principles of

conspiracy law,” which require no heightened

mens rea beyond what the underlying crime

requires.

In Collazo, a jury convicted the defendants of conspiracy

to distribute 500 grams of a mixture containing

methamphetamine in violation of 21 U.S.C. § 846, and the

district court sentenced defendants under

§ 841(b)(1)(A)(viii). 984 F.3d at 1317–18. The district court

instructed the jury to determine “whether the government

proved beyond a reasonable doubt that the amount of

methamphetamine that was reasonably foreseeable to [the

defendants] or fell within the scope of [their] particular

agreement equaled or exceeded . . . 500 grams of a mixture

containing methamphetamine.” Id. at 1317.

We held that this jury instruction was incorrect because

the conspiracy crime did not require the defendants’

knowledge of drug type and quantity. Id. at 1333. Relying

on “well-established principles of conspiracy law,” we

explained that a conspiracy conviction requires the

government to prove “(1) the defendant agreed with another

person that some member of the conspiracy would commit

the relevant underlying offense,” and “(2) the defendant had

the requisite intent necessary for a conviction of the

underlying offense.” Id. at 1318, 1320 (emphasis added).

Turning to the underlying offense, we observed that § 841(a)

makes it unlawful for any person to knowingly or

intentionally distribute “‘a controlled substance,’ which is an

unspecified substance listed on the federal drug schedules.”

Id. at 1325 (citation modified).

Although “the facts of drug type and quantity under

§ 841(b) constitute elements or ingredients of the crime

16 USA V. CASTRO ALAVEZ

because they affect the penalty that can be imposed on a

defendant,” id. at 1322, we concluded that there was “no

natural or ordinary way to read the intent requirement in

§ 841(a)(1) as modifying the drug types and quantities in

§ 841(b),” id. at 1326. Thus, “[b]ecause the government

need not prove that a defendant knew (or had an intent) with

respect to a specific drug type and quantity in order to secure

a conviction under § 841(a) . . . , the government likewise

need not prove such knowledge or intent for” a conspiracy

conviction under § 846. Id. at 1320 n.10, 1329.

We reached this conclusion because—unlike attempt—

conspiracy requires no greater mens rea than the underlying

offense. See id. at 1329–33. Relying on United States v.

Feola, 420 U.S. 671 (1975), we explained that “where an

element of the underlying substantive offense does not

include an intent requirement, the same will be true for a

conspiracy to commit that offense, unless one of the policies

behind the imposition of conspiratorial liability is not served

by having the same intent.” Id. at 1330 (citation modified).

For § 846, “the offense of conspiracy to distribute a

controlled substance is as ‘opprobrious’ and dangerous to

society as the act of the individual drug dealer who actually

distributes the controlled substance,” and so imposing an

additional burden on the government to prove the

conspirator’s knowledge of drug type and quantity would

serve “no apparent purpose.” Id. at 1332–33 (quoting Feola,

420 U.S. at 693, 694).

Indeed, our court has repeatedly upheld convictions for

conspiracy based only on the mens rea required for the

underlying crime. In United States v. Karr, 742 F.2d 493 (9th

Cir. 1984), we held that the defendant could be found guilty

of conspiring to receive stolen explosives even though he did

not know the materials were stolen, because the underlying

USA V. CASTRO ALAVEZ 17

offense required only that an individual have “reasonable

cause to believe” the materials were stolen. Id. at 497

(citation modified). So too in United States v. Thomas, 887

F.2d 1341 (9th Cir. 1989), where we upheld a conviction for

conspiracy to transport, receive, and acquire elk in interstate

commerce in violation of state law based only on proof that

the defendant “should have known” the conduct violated

state law. Id. at 1346–47. And in United States v. Baker, 63

F.3d 1478 (9th Cir. 1995), we held that “the defendants

c[ould] be guilty of conspiring to violate RICO even if they

were not aware their actions were illegal.” Id. at 1493. This

was because “establishing a defendant’s guilt of conspiracy

to commit a substantive crime requires proof of the mens rea

essential for conviction of the substantive offense itself. No

greater or different intent is necessary.” Id. (emphasis

added) (citation omitted).

B. Collazo’s reasoning cannot be grafted onto

attempted possession.

Hunt’s reasoning is not clearly irreconcilable with

Collazo. Collazo rests on the principle that conspiracy

requires no greater level of intent than the underlying crime.

But that principle does not apply to attempt. While

conspiracy demands “proof of the mens rea essential for

conviction of the substantive offense itself,” Baker, 63 F.3d

at 1493, attempt requires specific intent even when the

underlying crime does not, see Gracidas-Ulibarry, 231 F.3d

at 1193. This distinction makes sense. We require specific

intent for attempt to ensure that a defendant’s “purpose was

indeed to engage in criminal, rather than innocent, conduct.”

Id. at 1192–93. But the same rationale does not apply to

conspiracy, because “[t]he agreement itself is the offense.”

Collazo, 984 F.3d at 1319. Thus, because the mens rea for

attempt differs from the mens rea for conspiracy, the

18 USA V. CASTRO ALAVEZ

government fails to show that Hunt is irreconcilable with

Collazo’s conspiracy-specific reasoning.

The government also argues that it is illogical to apply

Collazo to conspiracy to possess but not attempted

possession, because both crimes are inchoate offenses

covered by the same statute. To be sure, applying Hunt and

Collazo yields different outcomes for Castro Alavez’s

conspiracy conviction and his attempted possession

conviction. But there is nothing illogical about this result. At

most, the government highlights that there might be some

tension between the two cases. Even so, mere tension is not

a valid basis to disregard precedent. Lair, 697 F.3d at 1207

(“It is not enough for there to be some tension between the

intervening higher authority and prior circuit precedent, or

for the intervening higher authority to cast doubt on the prior

circuit precedent.” (citation modified)).

In sum, Collazo does not apply here, and we are bound

by Hunt.

III. The district court improperly allowed Detective

Kelly Moniz to testify about the significance of

Jesus Malverde and Santa Muerte, but the error

was harmless.

At trial, the government called Detective Kelly Moniz as

an expert witness on drug trafficking methods and valuation.

Detective Moniz testified that the drawings seized from

Castro Alavez’s bag depicted Jesus Malverde and Santa

Muerte, and that these are Mexican patron saints that drug

traffickers pray to for protection, wealth, abundance, and

USA V. CASTRO ALAVEZ 19

silence. Castro Alavez argues the district court plainly erred

by admitting this testimony. 3

Under plain error review, Castro Alavez must show:

(1) an error; (2) that is plain; and (3) that affected his

substantial rights. See United States v. Olano, 507 U.S. 725,

732–36 (1993). “If these conditions are met, we may

exercise our discretion to notice the forfeited error only if the

error seriously affects the fairness, integrity, or public

reputation of judicial proceedings.” United States v.

Mendoza-Paz, 286 F.3d 1104, 1113 (9th Cir. 2002) (citation

modified).

The district court’s admission of Detective Moniz’s

testimony plainly contravened Federal Rule of Evidence

702, but Castro Alavez fails to show that the error affected

his substantial rights.

A. The district court abandoned its gatekeeping role.

Rule 702 allows a “witness who is qualified as an expert

by knowledge, skill, experience, training, or education” to

give opinion testimony if the expert’s “specialized

knowledge will help the trier of fact to understand the

evidence or to determine a fact in issue.” Fed. R. Evid.

702(a). “[B]efore admitting expert testimony, the district

court must perform a gatekeeping role to ensure that the

testimony is both relevant and reliable.” United States v.

Valencia-Lopez, 971 F.3d 891, 897–98 (9th Cir. 2020)

(citation modified).

The reliability of an expert’s testimony “is the lynchpin.”

Id. at 898. The reliability requirement ensures “that an

3

Castro Alavez concedes that he forfeited his objection to Detective

Moniz’s testimony, and thus plain error review applies. See Tan Lam,

976 F.3d at 1006.

20 USA V. CASTRO ALAVEZ

expert, whether basing testimony upon professional studies

or personal experience, employs in the courtroom the same

level of intellectual rigor that characterizes the practice of an

expert in the relevant field.” Kumho Tire Co. v. Carmichael,

526 U.S. 137, 152 (1999). When law enforcement officers

are offered as experts, “reliability depends heavily on the

knowledge and experience of the expert, rather than the

methodology or theory behind [the testimony].” Mendoza-

Paz, 286 F.3d at 1112 (citation modified).

Because the reliability analysis “is a malleable one tied

to the facts of each case,” district courts have “broad

latitude” to decide how to test an expert’s reliability. United

States v. Ruvalcaba-Garcia, 923 F.3d 1183, 1189 (9th Cir.

2019) (citation modified). But they “do not have discretion

to abandon the gatekeeping function altogether.” Id. (citation

modified). Here, the district court neglected its gatekeeping

role when it allowed Detective Moniz to testify about

religious iconography purportedly associated with drug

trafficking.

Detective Moniz has twenty years of experience as a law

enforcement officer and has investigated more than 300

narcotics-related cases. He no doubt has sufficient

knowledge and experience to qualify as an expert in drug

valuation and drug trafficking methods. But that expertise,

alone, does not qualify him to testify about every matter

remotely related to drug trafficking. See Valencia-Lopez,

971 F.3d at 900 (“[The expert’s] qualifications and

experience are relevant, and indeed necessary. But they

cannot establish the reliability and thus the admissibility of

the expert testimony at issue.”).

The government points to slim evidence that Detective

Moniz knows anything about religious iconography

USA V. CASTRO ALAVEZ 21

associated with drug trafficking. His experience is limited to

one four-hour class in 2010 and another in 2022. He never

investigated or researched the subject; nor had he served as

an expert on the subject before this case. Across hundreds of

investigations, Detective Moniz has only encountered Jesus

Malverde iconography one other time. The government

offers no other basis to support the reliability of Detective

Moniz’s testimony.

These qualifications fall short of Rule 702’s demanding

standard. Cf. Mendoza-Paz, 286 F.3d at 1112–13 (finding

that the expert was qualified to testify about the value of the

seized drugs because the expert “had investigated illegal

narcotics trafficking for eleven years” and had “obtained

experience in the value of illegal narcotics from intelligence

databases” and investigations he conducted). Detective

Moniz’s minimal exposure to drug-related religious

iconography rendered his opinion unreliable. See Valencia-

Lopez, 971 F.3d at 900. We thus hold that the district court

erred by allowing him to testify on the subject.

B. Detective Moniz’s testimony did not affect Castro

Alavez’s substantial rights.

For an error to affect a defendant’s substantial rights,

“the error must have been prejudicial,” which means “[i]t

must have affected the outcome of the district court

proceedings.” Olano, 507 U.S. at 734. Castro Alavez fails to

demonstrate a reasonable probability that absent Detective

Moniz’s testimony, the jury would have returned a verdict of

not guilty on the conspiracy charge. See id. (explaining that

the defendant has the burden to show prejudice); United

States v. Rangel-Guzman, 752 F.3d 1222, 1224 (9th Cir.

2014).

22 USA V. CASTRO ALAVEZ

The evidence incriminating Castro Alavez was

extensive. Besides the circumstantial evidence implicating

him in drug trafficking, Castro Alavez admitted that he was

involved in drug trafficking and that he knew the package

that arrived at Machado’s residence likely contained drugs.

Because Castro Alavez fails to show a reasonable probability

that Detective Moniz’s testimony affected the jury’s verdict,

we affirm his convictions. 4

CONCLUSION

We vacate Castro Alavez’s sentence for attempted

possession with the intent to distribute a controlled substance

but affirm his convictions for attempted possession and

conspiracy to possess a controlled substance. We remand for

further proceedings consistent with this opinion.

AFFIRMED in part, VACATED in part, and

REMANDED.

4

Castro Alavez also argues that the district court abused its discretion by

admitting the drawings that depicted Jesus Malverde and Santa Muerte.

We need not reach this issue because we are persuaded that any error is

harmless for the same reasons that Detective Moniz’s testimony did not

affect Castro Alavez’s substantial rights. See Olano, 507 U.S. at 734

(explaining that the plain error standard “normally requires the same

kind of inquiry” as the “harmless error” standard except that the burden

of persuasion is on the defendant instead of the government).