Hien Hai Hoac and Ngai Choy Chan appeal their convictions and sentences resulting from their participation in a scheme to import what proved to be the largest amount of heroin ever seized in the Central District of California. Both appellants raise a host of procedural and evidentiary issues. Hoac argues that the district court erred by excluding his proffered expert testimony, permitting a prosecutorial closing argument that violated his Fifth Améndment rights, admitting an incriminating statement of Chan’s, and declining to adjust his base offense level downward for being a minor participant. Chan alleges error in the admission of Hoac’s redacted confession, the court’s failure to give a statutorily required instruction on volun- *1102 tariness, and the increase of his base offense level for being an organizer, leader, manager, or supervisor. We reject all of these arguments but the last. We therefore affirm both convictions and Hoac’s sentence, but we vacate Chan’s sentence and remand for resentencing.
BACKGROUND
On December 21, 1989, the United States Customs Service intercepted a shipment of 1000 cases of lychee nuts, originating from Hong Kong, at Long Beach Harbor. Eight cases were specially marked with the num-' ber “8”; these cases were found to contain a total of approximately 55.74 kilograms of heroin with a purity of 77 percent.
The consignee of the shipment was Bea Kea Hong Imports, owned by appellant Hoac. Drug Enforcement Administration (DEA) agents tracked the shipment as it was delivered to a Los Angeles warehouse leased by Hoac. They watched Hoac unload the shipment into the warehouse, with the exception of the eight cases of heroin, which he loaded into a van. The agents then followed Hoac as he drove the van in a counter-surveillance manner. Concerned that Hoac was aware he was being followed, the agents stopped the van and arrested Hoac. Hoac waived his Miranda rights and agreed to assist in a controlled delivery of the heroin to its intended recipient, codefendant Chau Ngoc Au. Au was arrested accepting delivery of the eight cases from Hoac.
At the police station, Hoac told DEA Special Agent James Tse that he had met with Chan and codefendant Wai-Chong Leung in Hong Kong in September 1989 to discuss the shipment of lychee nuts. Hoac stated that in December 1989 he had also met with Leung and Au in Vancouver regarding the shipment. He understood that he was to be paid $80,000 for delivery of the boxes to Au. (At the time of his arrest, Hoac had given conflicting responses— $50,000, followed by $10,000 or $20,000— when asked what he expected to be paid for delivering the eight cases to Au.)
On January 7, 1990, the Royal Hong Kong Police took Chan into custody as he was leaving Hong Kong by ferry. A search of Chan’s residence revealed documents relating to the lychee shipment and a lease agreement and keys to a Hong Kong warehouse. In the warehouse the police found two boxes of lychee nuts, assorted handsaws and welding tools, and traces of morphine. Chan was informed of his rights and made three statements to Royal Hong Kong Police Officer Wai Yip Ng. He said that Leung had approached him and asked him to open up a trading company to ship lychee nuts to the United States. Chan opened the trading company,, obtained a business registration certificate, reserved a shipping date, and arranged a container for transportation. He and Leung cut open the cans in eight boxes of lychee nuts, filled them with heroin, and resealed the cans with a welding tool. They then packed those boxes with 992 untampered boxes into a shipping container. Leung paid Chan $10,000 (Hong Kong) and promised him an additional $50,000-$70,000 if the shipment was successful.
Hoac, Chan, and Au were tried together before a jury. 1 Hoac and Chan were both convicted of conspiracy to import and distribute heroin, conspiracy with intent to distribute heroin, and importation of heroin. Additionally, Hoac was convicted of attempted possession with the intent to distribute heroin and possession with the intent to distribute heroin, and Chan was convicted of distribution of heroin. Hoac was sentenced to 235 months in custody, a $100,000 fine, and five years of supervised release. Chan was sentenced to 292 months in custody, a $250,000 fine, and five years of supervised release.
DISCUSSION
I. Appellant Hoac
A. Exclusion of Proffered Expert Testimony
At trial Hoac sought to prove that he lacked knowledge of the heroin by introducing the testimony of Dr. Timothy Law, *1103 a clinical forensic psychologist who had examined Hoac on two occasions. The district court conducted a voir dire examination of Dr. Law to ascertain the substance of his testimony. Dr. Law proposed to give his opinion regarding Hoac’s intellect and general naivete and to testify about how Chinese cultural factors might lead Hoac to travel long distances for legitimate business dealings. The district court rejected Dr. Law’s proposed testimony, stating:
It seems to me that allowing testimony of this nature, that is the doctor's opinion after two relatively brief meetings, that the defendant struck him as being naive, it would not materially assist the jury with respect to the issues at hand and that Rule 403 would compel its exclusion because it would inject collateral matters with weak probative value and the effect would be to likely to [sic] create collateral issues and jury confusion. So, I am going to reject it.
Hoac argues that the district court’s exclusion of Dr. Law’s testimony was an abuse of discretion.
A qualified expert witness may testify if the witness’ “specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue.” Fed.R.Evid. 702;
United States v. Peralta,
Dr. Law had not performed any formal testing on Hoac and had spoken with him on only two occasions lasting approximately one hour each. Dr. Law’s knowledge about Hoac thus was limited and it is unlikely that his testimony would have helped the jury.
See United States v. Barnard,
B. The Prosecutor’s Closing Argument
In his rebuttal argument, the prosecutor stated to the jury:
[Hoac’s defense counsel] said that the defendant Hoac was used by others. That he was an innocent dupe.... And yet, [Hoac] never said that. He never said he was an innocent dupe. He was fully explained that he was being arrested for narcotics trafficking and he revealed his role. He never said that. He never said that the reason that there was counter surveillance driving is because he didn’t know who was behind him. That was argument of counsel.
Later, the prosecutor stated:
[Hoac] knew exactly what he was doing and he was told what he was being charged with, and he never said, ‘Well, I didn’t know it was drugs.’ He explained his role.
Hoac alleges that these comments violated his Fifth Amendment rights by referring to his failure to testify and his post-arrest, post-Miranda silence.
The standard of review for prosecu-torial comment on a defendant’s failure to testify or post-arrest silence is unclear.
Compare United States v. Mares,
The use for impeachment purposes of a defendant’s silence at the time of arrest and after receiving
Miranda
warnings violates due process.
Doyle v. Ohio,
a defendant who voluntarily speaks after receiving Miranda warnings has not been induced to remain silent. As to the subject matter of his statements, the defendant has not remained silent at all....
... Each of two inconsistent descriptions of events may be said to involve ‘silence’ insofar as it omits facts included in the other version. But Doyle does not require any such formalistic understanding of ‘silence’....
Anderson v. Charles,
Here, defense counsel presented Hoac’s version of events in opening and closing arguments. Hoac’s post-arrest statements meet the
Ochoa-Sanchez
requirement of being “arguably inconsistent” with the defense presented at trial,
see Diaz,
Nor did the prosecutor’s comments im-permissibly refer to Hoac’s failure to testify. While the Fifth Amendment prevents a prosecutor from commenting on an accused’s decision not to testify at trial,
see Griffin v. California,
The comments to which Hoac objects all referred to what he said or did not say at the time he was arrested, and were in no way phrased to comment on his failure to take the stand or produce evidence at trial. Nor were the prosecutor’s comments extensive or heavily emphasized. “[Wjhen taken in context and fairly construed, the comments do not appear to have been manifestly intended or to have been of such a character that the jury would necessarily take them as a comment on [Hoac’s] failure to testify.”
United States v. Soulard,
*1105 C. Admission of Chan’s Statement
At trial Royal Hong Kong Police Officer Ng, who took Chan’s statements, testified that Chan had said that he sent the shipment of heroin to Bea Kea Hong Imports. Over defense counsel’s objection, the prosecution introduced Chan’s handwritten note indicating that the shipment was going to Bea Kea Hong Imports, 1301 South Fremont Avenue, Alhambra, California. Chan never took the stand, and the court instructed the jury that these statements were only admissible against Chan. Hoac argues that the admission of this evidence violated his Sixth Amendment right of confrontation under
Bruton v. United States,
In
Bruton,
the Supreme Court held that the introduction of a nontestifying code-fendant’s confession violates a defendant’s Sixth Amendment right of confrontation, even if the judge instructs the jury that the confession is admissible only against the nontestifying codefendant.
Bruton,
[I]n this case the confession was not incriminating on its face, and became so only when linked with evidence introduced later at trial (the defendant’s own testimony).
Where the necessity of such linkage is involved, it is a less valid generalization that the jury will not likely obey the instruction to disregard the evidence. Specific testimony that “the defendant helped me commit the crime” is more vivid than inferential incrimination, and hence more difficult to be thrust out of mind.
Id.481 U.S. at 208 ,107 S.Ct. at 1707 (footnote omitted). In accordance with Richardson, this court has held that a codefendant’s statement that does not incriminate the defendant unless linked with other evidence introduced at trial does not violate the defendant’s Sixth Amendment rights. United States v. Sherlock,865 F.2d 1069 , 1080 (9th Cir.1989), amended,962 F.2d 1349 (9th Cir.), cert. denied, — U.S.-,113 S.Ct. 419 ,121 L.Ed.2d 342 (1992).
In this case, Chan’s confession and note never mentioned Hoac by name; rather, they revealed that Chan shipped the lychee nuts to a certain address in Alhambra, California, which address was linked to Hoac by other evidence. Moreover, the confession and note were not incriminating even when such linkage was established. Hoac never contested that he received the shipment of lychee nuts, but only contended that he was unaware of the contents; Chan’s statements led to no inference that Hoac had knowledge of the heroin. Under Richardson, the introduction of Chan’s statements was not a violation of Hoac’s Sixth Amendment rights.
D. Hoac’s Role in the Offense
Hoac argues that, the district court erred in failing to reduce his base offense level by two as a minor participant pursuant to § 3B1.2(b) of the Sentencing Guidelines. A defendant must prove his status as a minor participant by a preponderance of the evidence.
United States v. Howard,
Guidelines § 3B1.2 provides for a two-level reduction in the base offense level if the defendant was a “minor participant” in the offense and a four-level reduction if he was a “minimal, .participant.” The Application Notes define a minor participant as “any participant who is less culpable than most other participants, but whose role could not be described as minimal.” U.S.S.G. § 3B1.2, Application Note 3. The downward adjustment for minor or
*1106
minimal participants is to be used infrequently.
United States v. Gillock,
Hoac describes himself as a “courier” and argues that he is therefore “entitled” to a reduction in base offense level as a minor participant. The record contains ample evidence to support the view that Hoac was more than a mere courier. He owned the trading company and leased the warehouse to which the drugs were delivered, attended two foreign meetings to discuss the shipment with his coconspirators, and was paid a substantial sum for his participation. Because we conclude that Hoac’s involvement in the offense was greater than that of a courier, we do not reach the issue of whether one who is solely a courier is automatically entitled to a reduction of his base offense level as a minor participant.
See United States v. Flores-Payon,
Hoac also argues that the district court should have found him to be a minor participant because he had no ownership interest in the narcotics in his possession. We reject this argument. Hoac received and transported the narcotics in exchange for substantial compensation. Moreover, we have held that a defendant is not entitled to minor participant status merely because he may be less culpable than his codefendants.
United States v. Andrus,
II. Appellant Chan
A. Admission of Hoac’s Statement
DEA Special Agent James Tse testified at trial about statements that Hoac made after he was arrested. Although the Assistant United States Attorney had instructed Agent Tse not to refer by name to Chan, Tse testified on direct examination as follows:
Q: After these rights were given to [Hoac], did you have a further conversation regarding the eight boxes of lychee nuts that contained the heroin?
A: Yes.
Q: Can you tell us what he told you?
A: He told me that another individual was involved. He mentioned that his name was Anom.
“Anom” is an alias of Chan, although that information was never revealed to the jury.
Chan’s counsel informed the court in a sidebar that “Anom” was Chan and moved for a mistrial. The court rejected the motion, reasoning that “the jury doesn’t know that Anom is Chan and they have no way of perceiving that because there’s nothing in the case that links Anom to the name Chan. Plus, he didn’t say that Anom was a Hong Kong person, which might have a link.” The court concluded that any potential error could be cured by having Tse testify that he had previously misspoken when he mentioned the name Anom. Tse so testified on further direct examination. Tse’s testimony thereafter referred only to “individuals” with whom Hoac said he had met. Hoac did not testify at trial, and the court instructed the jury that Hoac’s hearsay statements were only admissible against Hoac. Chan argues that the admission of evidence of Hoac’s extrajudicial confession at trial was a violation of Chan’s Sixth Amendment right of confrontation under Bruton.
Redaction of a nontestifying codefendant’s confession, when accompanied by a proper limiting instruction, can prevent any
Bruton
violation.
Richardson,
In
United States v. Long,
In this case, Special Agent Tse used the neutral plural term “individuals” and did not indicate to the jury that Chan had given actual names or even had stated how many “individuals” he had met with in Hong Kong. The jury was aware that several people were involved in this conspiracy, including at least one (Leung) who was not being tried with the three defendants. Because “Anom” was never revealed to the jury to be Chan’s nickname and was immediately corrected and replaced with the vague plural “individuals,” and because the redaction did not invite the jury to “fill in the blanks,” Hoac’s extrajudicial statement did not facially incriminate Chan; rather, it could become incriminating only when linked' with other evidence introduced at trial.
See Richardson,
B. Failure to Give a Voluntariness In- ' struction
' 18 U.S.C. § 3501(a) provides in relevant part:
If the trial judge determines that [a] confession was voluntarily made it shall be admitted in evidence and the trial judge shall permit the jury to hear relevant evidence on the issue of voluntariness and shall instruct the jury to give such weight to the confession as the jury feels it deserves under all the circumstances.
Thus, where a defendant raises a genuine issue at trial concerning the voluntariness of a statement, the trial court is obligated by statute to instruct the jury concerning the weight to be accorded that statement.
United States v. Fera,
Chan’s counsel devoted the majority of her cross-examination of the Hong Kong police witnesses and her closing argument to the circumstances of Chan’s *1108 statements, which she argued included overly long periods of questioning, sleep deprivation, and unnecessary use of handcuffs and hoods. That she did not ultimately persuade the jury to disregard the statements does not mean that the weight to be given the statements was not in issue. The district court therefore properly recognized that a § 3501(a) instruction was required, although it rejected Chan’s proposed instruction 3 in favor of Ninth Circuit Model Criminal Jury Instruction 4.01. 4 Only moments after ruling that it would give the preferred Ninth Circuit instruction, however, the district court failed to give any instruction regarding a defendant’s extrajudicial statements. Chan argues that this was error requiring reversal of his conviction.
Because Chan did not object to the district court’s apparently inadvertent omission when the instructions were given, we review for plain error.
United States v. Boone,
Although we have stated that improper jury instructions will rarely justify a finding of plain error,
id.
at 1367-68, we are necessarily more cautious when the trial court omits an instruction that is .unequivocally mandated by statute. We are also aware that several circuits have held that a failure to issue a § 3501(a) instruction when voluntariness is in issue is plain error
per se,
focusing their analysis on whether the error was harmless beyond a reasonable doubt.
See United States v. McLernon,
Without referring to the Supreme Court’s words in
Young,
some of our cases have indicated that a plain error can also be harmless error.
See United States v. Payne,
Our plain error analysis must therefore turn not on any
per se
rule, but on whether the district court’s failure to give the required instruction, under all of the circumstances presented, was so prejudicial that it tainted the verdict or deprived Chan of a fair trial. We conclude that it was not. Chan’s confession was corroborated by the physical evidence, including his ownership of the company that shipped the lychees and his possession of documents relating to the shipment as well as the lease and keys to the packing warehouse. Further evidence indicated that Chan was repeatedly read his rights, signed three separate statements after being permitted to read and correct them, and was given approximately seven hours in a cell to sleep between interviews. All insinuations by Chan’s counsel of threats and intimidation were denied on the stand by
*1110
the Hong Kong Police witnesses,
7
whose trustworthiness the jury was instructed to weigh by the court's general credibility instruction.
See United States v. Williams,
C. Chan’s Role in the Offense
Finally, Chan argues that the district court erred by increasing his base offense level by two for his aggravating role as “an organizer, leader, manager, or supervisor” of the heroin conspiracy under U.S.S.G. § 3Bl.l(c). To justify a two-level increase under § 3Bl.l(c), the government must prove by a preponderance of the evidence that the defendant had an aggravating role in the offense.
See United States v. Mares-Molina,
In
Mares-Molina,
this court adopted a First Circuit holding that for an upward adjustment under § 3B1.1 “ ‘the defendant must have exercised some control over others involved in the commission of the offense or he must have been responsible for organizing others for the purpose of carrying out the crime.’ ”
Id.
(quoting
United States v. Fuller,
We do not believe that the district court, properly applying the Mares-Molina standard, could have found by a preponderance of the evidence that Chan was “an organizer, leader, manager, or supervisor” under § 3Bl.l(c). At sentencing the government argued that the two-level increase was justified because Chan opened the trading company to export the heroin, reserved a shipping date and arranged for a shipping container, assisted Leung in placing the heroin in the cans and loading the shipping container, was promised $50,000-$70,000 by Leung if the shipment was successful, and at the time of his arrest possessed the rental contract and keys for the packing *1111 warehouse. While all of these facts suggest that Chan was perhaps one of the more culpable defendants, they do not indicate that he exercised “control over others” or was “responsible for organizing others” so as to justify an increase under § 8Bl.l(e). Moreover, the court justified the two-level increase by stating: “[Chan] didn’t organize the whole scenario ... I mean, it seems that Mr. Leung did that_ But [Chan] implemented the importation and in that, utilized organization skills.” Organizing the importation, however, is not the same as organizing other conspirators and does not satisfy Mares-Molina.
Because no evidence indicated that Chan exercised control over other defendants or was responsible for organizing' them, 8 Mares-Molina requires us to hold that the district court’s finding that Chan was “an organizer, leader, manager, or supervisor” was clearly erroneous. We therefore vacate Chan’s sentence and remand for resen-tencing in accordance with this opinion.
AFFIRMED IN PART, REVERSED IN PART, AND REMANDED IN PART.
Notes
. Leung, a fugitive at the time of trial, was subsequently apprehended, tried, and convicted.
. Other circuits have held that no such correlation exists.
See United States v. McCann,
. Chan requested the following instruction:
Evidence relating to any statement, or act or omission, claimed to have been made or done by a defendant outside of court, and after a crime has been committed, should always be considered with caution and weighed with great care; and all such evidence should be disregarded entirely, unless the evidence in the case convinces the jury beyond a reasonable doubt that the statement or act or omission was knowingly made or done.
A statement or act or omission is "knowingly" made or done, if done voluntarily and intentionally, and not because of mistake or accident or other innocent reason.
If after considering the evidence you determine that a statement, act or admission [sic] was knowingly made or done, you will give it such weight as you feel it deserves under the circumstances.
. The Ninth Circuit instruction provides:
You have heard testimony that the defendant made a statement. It is for you to decide (1) whether the defendant made the statement and (2) if so, how much weight to give to it. In making those decisions, you should consider all of the evidence about the statement, including the circumstances under which the defendant may have made it.
9th Cir.Crim.Jury Instr. 4.01 (1992). This instruction satisfies the requirements of § 3501(a), and there was no error in rejecting Chan’s alternative instruction.
United States v. Solomon,
. The explanation for some of our cases to the contrary, we believe, is the tendency to give "plain” its ordinary meaning of "obvious.”
See, e.g., United States v. Wilson,
. In holding that all plain errors are harmful, we do not imply that all harmful errors are plain. The Supreme Court has made clear that “Rule 52(b) is to be used sparingly, solely in those circumstances in which a miscarriage of justice would otherwise result."
United States v. Frady,
. The following is a representative sample of Chan’s cross-examination of Officer Ng:
Q. Mr. Ng, isn’t it true that at the beginning of interview [sic] Officer Chung told Mr. Chan that he has [sic] going to die?
A. No.
Q. Isn't it true that he threatened him and said, “You will die sooner"?
A. No.
Q. Following that trip, sir, isn’t you true [sic] Mr. Chan said, “I will sign anything you want me to”?
A. No.
. The only evidence that could arguably support an increase under § 3Bl.l(c) is Chan’s statement that he and Leung were partners. We conclude that this alone is insufficient to satisfy Mares-Molina.
