OPINION OF THE COURT
This ease requires us to review the factors a district court should consider in deciding whether a drug courier or “mule” convicted of importation may be characterized as a minor participant in the offense, such that a downward adjustment in sentencing pursuant to § 3B1.2 of the United States Sentencing Guidelines may be warranted. The district court concluded that, as a courier, the defendant’s role was “essential” and he was not a minor participant. Because we cannot determine whether this conclusion was a factual finding, or was based on an interpretation of the sentencing guidelines, we will vacate and remand for resentencing consistent with this opinion.
See United States v. Mummert,
I.
While in Colombia on a vacation, Oscar Ivan Isaza-Zapata was approached by two men, Carlos and Tyson, in a park. The men offered to pay him $16,000 to transport 800 grams of heroin to the United States. In need of money for a foot operation, Isaza-Zapata agreed. He later met Carlos and Tyson at a hotel in Perriera, Colombia, where they gave him 100 pellets of heroin to swallow. They provided him with a ticket to Newark, where he was to meet another man named Carlos.
Upon his arrival at Newark International Airport, Isaza-Zapata was subjected to a routine customs examination. After his demeanor aroused suspicion, Isaza-Zapata was asked to consent to an X-ray examination. Isaza-Zapata signed the consent form and was transported to Bayonne Medical Center, where he passed approximately 100 pellets containing heroin. He advised the customs agents that he had been paid to bring narcotics into the United States. Isaza-Zapata attempted to cooperate with Customs officials by placing a call .to his United States contact, but was unsuccessful.
In a one count indictment, the grand jury charged Isaza-Zapata with knowingly and intentionally importing into the United States more than 100 grams of heroin in violation of 21 U.S.C. §§ 952(a) & 960(a)(1), and 18 U.S.C. § 2. Isaza-Zapata subsequently pled guilty.- At sentencing, he requested a two-point downward adjustment in his offense level as a minor participant. The government agreed that Isaza-Zapata was entitled to the downward adjustment. The district court, however, declined to grant the adjustment. The court sentenced Isaza-Zapata to 60 months imprisonment, four years supervised release, a $1,000 fine, and a special ■ assessment of $100. This appeal followed.
II.
The district court had jurisdiction pursuant to 18 U.S.C. § 3231, and we have jurisdiction pursuant to 28 U.S.C. § 1291 and 18 U.S.C. § 3742. We employ a mixed standard of review when considering whether a defendant was entitled to a downward adjustment as a minor participant.
See United States v. Carr,
At the sentencing hearing, the distinct court denied the two-point downward adjustment, stating only that “I find that his role is essential for the commission of the crime and that he is not a minor participant.” The district court did not set forth any other reasons for its determination, and it is not clear whether the district court assessed the relative culpability of Isaza-Zapata as compared .to others and considered the factors
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we have outlined in
United States v. Headley,
We do not hold that the district court erred in refusing to grant Isaza-Zapata a minor role adjustment. .We are simply unable to determine the basis of the district court’s ruling from the record. Since our standard of review turns on whether the court denied the downward adjustment based on a proper legal interpretation of the mitigating role provision based on the facts 'of this particular case,
see Carr,
III.
The Sentencing Guidelines permit adjustments to a defendant’s offense level based on the role that he played in committing the offense. Section 3B1.2 affords a reduction in the offense level if the defendant was either a minimal or a minor participant:
Based on the defendant’s role in the offense, decrease the offense level as follows:
(a) If the defendant was a minimal participant in any criminal activity, decrease by 4 levels.
(b) If the defendant was a minor participant in an y criminal activity, decrease by 2 levels.
In cases falling between (a) and (b), decrease by 3 levels.
U.S. Sentencing Guidelines Manual § 3B1.2. The district courts are allowed broad discretion in applying this section, and their rulings are left largely undisturbed by the courts of appeal. See United States Sentencing Commission, 1996 Sourcebook of Federal Sentencing Statistics (1996) (stating that the affir-mance rate under § 3B1.2 is 99.3%).
The background commentary to this provision indicates that its application is heavily dependent on the facts of a particular case, and that the reduction is available for a .defendant whose role in the offense makes him substantially less culpable than the average participant.
See
U.S. Sentencing Guidelines Manual § 3B1.2, Background Commentary. Section 3B1.2 does not itself define the term “participant,” but an application note to § 3B1.1, which addresses a defendant’s aggravating role in the offense, defines a participant as “a person who is criminally responsible for the commission of the offense, but need not have been convicted. A person who is not criminally ■ responsible for the commission of the offense
{e.g.,
an undercover law enforcement officer) is not a participant.” U.S. Sentencing Guidelines Manual § 3B1.1, Application Note 1. That same definition of “participant” should also apply to the mitigating role provision.
See United States v. Katora,
It is clear that the adjustments for a defendant’s role in the offense apply where there has been concerted activity involving one or more participants. The application notes indicate that “a minor participant means any participant who is less culpable than most other participants, but whose role could not be described as minimal.” U.S. Sentencing Guidelines Manual §' 3B1.2, Application Note 3. The notes further explain that a defendant who plays a minimal role in concerted activity is one who is among the least culpable of those involved in the group conduct. Such factors as a defendant’s lack of knowledge or understanding of the overall
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enterprise and of others’ activities are evidence of a minimal role in the offense.
See
U.S. Sentencing Guidelines Manual § 3B1.2, Application Note 1. Thus, the two prerequisites to the application of § 3B1.2 are multiple participants and a differentiation in levels of culpability.
See Katora,
In
Headley,
we adopted the following principles, as enunciated by the Second Circuit, as relevant to the determination of whether a courier is a minor participant: “ ‘[t]he culpability of a defendant courier must depend necessarily on such factors as the nature of the defendant’s relationship to the other participants, the importance of the defendant’s actions to the success of the venture, and the defendant’s awareness of the nature and scope of the criminal enterprise.” ’
Since § 3B1.2 is ultimately concerned with the defendant’s relative culpability, a district court should consider the defendant’s conduct under the
Headley
factors in relation to the other participants.'
See Bierley,
In 1990, the Sentencing Commission clarified the scope of the conduct relevant to the role in the offense adjustment, and the introductory ’ commentary now directs' that the determination of the defendant’s relative culpability for purposes of’ assessing the applicability of the adjustment must be made on the basis of all relevant conduct — namely, all conduct within the scope-of■§ 1B1.3 — and not simply on the basis of the elements and acts referenced in the count of conviction.
1
See
U.S. Sentencing Guidelines Manual, Ch. 3, Pt. B, intro, comment;
see also Headley,
Although some of the courts considering this issúe have noted the centrality or essen
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tial nature of the courier’s role, they have done so in pointed response to the defendants’ contentions that a courier should automatically qualify for a minor role adjustment, and have proceeded then to engage in an analysis of the defendant’s conduct in relation to others.
See United States v. Walker,
The defendant bears the burden of demonstrating that other participants were involved and that, under the standards set forth above and the facts of his particular case, the minor role adjustment should apply.
See Price,
Although this offense involving several participants with different roles is exactly the type of situation in which a minor role adjustment should be considered, two arguments are commonly advanced to discourage the application of the minor role adjustment in this type of case. First, the government contends that a courier like Isaza-Zapata, who is not charged with conspiracy, does not play a minor role in the importation with which he is charged. However, the fact that no conspiracy is charged does not preclude consideration of the minor role adjustment as long as other participants were involved in the relevant conduct. Even if the defendant is charged only with, for example, importation or receiving stolen goods, if the evidence demonstrates that other participants were involved, the district court can consider whether the defendant played a minor role in the relevant conduct.
See Bierley,
Second, the government argues that no minor role adjustment is available where the defendant is charged only with the amount of drugs or money with which he was involved, or which he, in this instance, carried. The scope of the relevant conduct that a court should consider in assessing the applicability of the minor role adjustment, however, is broader than merely the conduct required by the elements of the offense of conviction. Even if a courier is charged with importing only the quantity of drugs that he actually carried, there may still be other participants involved in the conduct relevant to that small amount or that one transaction.
See United States v. Rodriguez De Varon,
The Seventh Circuit has expressed skepticism as to a defendant’s entitlement to a minor role adjustment in such a situation. In
United States v. Lampkins,
the court stated that where a defendant is sentenced only for the quantity of drugs that he himself handled, “it makes no sense to claim that [he] is a minor participant in [his] own conduct.”
We disagree with
Burnett.
The district court must examine
all
relevant conduct, not merely the defendant’s, in assessing his relative culpability. The Eleventh Circuit shares this view. In
Rodriguez De Varón,
the Eleventh Circuit expressly stated that “[w]e reject [the] rationale [of
Burnett
and
Lamp-
kins].”
See
Accordingly, although the amount of drugs with which the defendant is charged may be an important factor which weighs heavily in the court’s view of the defendant’s relative culpability, it does not necessarily preclude a minor role adjustment with one exception. Application Note 4 to § 3B1.2 indicates that a downward adjustment as a minor participant is not available to a defendant who has already received a lower offense level by virtue of being convicted of a substantially less serious offense than warranted by his actual conduct.
See
U.S. Sentencing Guidelines Manual .§ 3B1.2, Application Note 4. If this provision applies, the adjustment is not warranted. Courts have consistently applied this provision to preclude a minor role adjustment to defendants convicted of offenses less serious than warranted by their actual conduct. For example, where a larger conspiracy in which the defendant was involved is not taken into account in the charged offense that sets the defendant’s base offense level, the defendant is not entitled to a reduction for his minor role in that conspiracy.
See United States v. Gomez,
There may be some crimes which by their nature will normally involve only the defendant as the sole participant in the offense of conviction.
See United States v. Romualdi,
Accordingly, the mere fact that a courier was not charged with conspiracy or was charged only with the amount of drugs in his possession does not necessarily preclude consideration of a minor role adjustment. By the same token, a courier is not automatically entitled to a minor role adjustment.
See Headley,
IV.
For the foregoing reasons, we will vacate the sentence and remand for resentencing consistent with this opinion.
Notes
. Section lB1.3(a) defines relevant conduct as:
(1)(A) all acts and omissions committed, aided, abetted, counseled, commanded, induced, procured, or willfully caused by the defendant; • and
(B) in the case of a jointly undertaken criminal activity (a criminal plan, scheme, endeavor, or enterprise undertaken by the defendant in concert with others, whether or not charged as a conspiracy), all reasonably foreseeable acts and omissions of others in furtherance of the jointly undertaken criminal activity, that occurred during the commission of the offense of conviction, in preparation for that offense, or in the course of attempting to avoid detection or responsibility for that offense;
(2) solely with respect to offenses of a character for which § 3D 1.2(d) would require grouping of multiple counts, all acts and omissions described in subdivisions (1)(A) and (1)(B) above that were part of the same course of conduct or common scheme or plan as the offense of conviction;
(3) all harm that resulted from the acts and omissions specified in subsections (a)(1) and (a)(2) above, and all harm that was the object of such acts and omissions; and
(4) any other information specified in the applicable guideline
. We note that it is not entirely clear that the holding of
Burnett
would preclude a minor role adjustment every time a defendant is sentenced on the basis only of the amount of drugs with which he was directly involved. The court, although affirming the district court's denial of the minor role adjustment, emphasized the discretion of the district court and specifically stated that it would not have disturbed the decision even if the district court had ruled the other way.
See
