In the
 United States Court of Appeals
               For the Seventh Circuit
                          ____________

No. 07-2522
UNITED STATES OF AMERICA,
                                                   Plaintiff-Appellee,
                                  v.

MUHAMMAD KHATTAB,
                                               Defendant-Appellant.
                          ____________
             Appeal from the United States District Court
        for the Northern District of Illinois, Eastern Division.
             No. 05 CR 497—Matthew F. Kennelly, Judge.
                          ____________
       ARGUED JUNE 5, 2008—DECIDED AUGUST 5, 2008
                          ____________


  Before POSNER, KANNE, and SYKES, Circuit Judges.
  KANNE, Circuit Judge. Muhammad Khattab was con-
victed after a bench trial on one count of attempting
to possess or distribute pseudoephedrine with knowl-
edge, or a reasonable cause to believe, that it would be
used to manufacture methamphetamine. See 21 U.S.C.
§ 846; see also 

Khattab claims that the evi-
dence presented at trial was insufficient to sustain his
conviction. We disagree, and affirm.
2                                               No. 07-2522

                        I. HISTORY
  In early 2005, Muhammad Khattab began negotiating
with Khalid Hassan for the purchase of a large quantity
of pseudoephedrine. Unbeknownst to Khattab, Hassan
was a confidential informant for the Drug Enforcement
Agency (DEA), and recorded his telephone conversa-
tions with Khattab. On April 22, 2005, Khattab met in
person with Hassan and another man at an auto-parts
store. Hassan wore a recording device, which picked up a
conversation in Arabic between the three men about the
prospective sale. Khattab communicated with Hassan on
several other occasions, all of which were monitored and
recorded by the government. Over the course of these
conversations, Hassan told Khattab that he had a con-
tact who could sell Khattab 100 boxes of pseudoephedrine.
  On May 31, 2005, Khattab and Hassan scheduled a
meeting with DEA Agent James Jones, who posed as a
deliveryman for Hassan’s fictitious pseudoephedrine
supplier. Khattab and Hassan drove to the site where
they were supposed to meet Jones, but Khattab became
nervous because of the potential presence of law enforce-
ment officers in the area, and cancelled the meeting.
Khattab and Hassan then drove around and rescheduled
the meeting for a different location later that same day. The
three men met on the South Side of Chicago in an alley
behind a gas station, where Agent Jones opened the back
of his van and showed Khattab 100 boxes of
pseudoephedrine. Khattab gave Jones $3,000 in
cash—double the price that Jones had paid a wholesale
supplier for the drugs. Khattab began moving the
pseudoephedrine from Jones’s van to his own vehicle
when other DEA agents, who had been conducting sur-
veillance at the scene, emerged and identified themselves.
No. 07-2522                                             3

Khattab panicked and attempted to flee, but the agents
apprehended him about 20 yards away.
  Khattab was indicted on one count of attempting
to knowingly or intentionally possess or distribute
pseudoephedrine with knowledge, or a reasonable cause
to believe, that it would be used to manufacture a sub-
stance containing detectable amounts of methamphet-
amine. See 

see also 

Khattab
waived his right to a jury trial, and in late January 2007
the case proceeded to a bench trial.
  At trial, the government introduced testimony from
DEA Special Agent Wilfred Taylor, who stated that
pseudoephedrine is an over-the-counter drug that is
legally used to relieve respiratory congestion. Taylor
explained that pseudoephedrine can be converted into
methamphetamine, an illicit narcotic that users ingest by
sniffing the powder, smoking a mixture containing the
powder, or injecting the drug intravenously. Taylor
testified that because pseudoephedrine is the key ingredi-
ent in manufacturing methamphetamine, it has a high
likelihood of being “diverted” for illegal purposes. The
risk of diversion has led the DEA to impose many re-
strictions on the packaging, sale, and purchase of
pseudoephedrine. For example, although pseudoephedrine
was previously available for retail in bottles containing
loose pills, the drug is now sold at the retail level only
in “blister packs,” with each pill individually wrapped.
Taylor indicated that wholesalers still sell cases of
pseudoephedrine in loose, bottle form—each case con-
tains 144 bottles of 60 pills, or 8,640 pills per case—but
the wholesalers need a DEA license to import, export,
or distribute cases.
4                                              No. 07-2522

  Taylor also testified about his knowledge of metham-
phetamine production. He explained that some recipes
for manufacturing methamphetamine call for the use of
bulk amounts of 60 milligram pseudoephedrine tablets,
which leads methamphetamine producers to prefer bottles
of loose pills over individually wrapped blister packs
because the loose pills allow for more rapid processing.
Taylor also noted that methamphetamine producers use
the number “8,640” as a code word referring to a bulk
amount of pseudoephedrine. And Taylor explained
that Khattab was arrested while attempting to possess
57,600 tablets of pseudoephedrine—a bulk amount not
intended for personal use that “[could] treat 2,000 people
[for respiratory congestion] over a seven-day period.”
  Taylor testified that in his experience investigating
the illicit uses of pseudoephedrine, he had never dis-
covered any legitimate use for bulk quantities of
pseudoephedrine that are sold outside of DEA licensing
restrictions. Two other DEA witnesses elaborated that
they were unaware of any illegal black-market uses of
bulk amounts of pseudoephedrine, apart from the pro-
duction of methamphetamine. The government then
presented testimony from Agent Jones and two other
DEA agents concerning the attempted drug sale that led
to Khattab’s arrest.
  Additionally, the government introduced transcripts
containing English translations of eleven recorded tele-
phone conversations and the April 22 meeting. Agent
Jones laid foundation for the admission of the transcripts
by identifying the voice on the recordings as Khattab’s
voice. The government also called a linguist, Bassam
Abbasi, who testified that the government transcripts
reflected an accurate translation of the Arabic dialogue in
No. 07-2522                                                5

the recordings. The transcripts were admitted into evi-
dence.
  The transcript of the April 22 meeting revealed several
statements, made either by Khattab or in his presence,
that referred to extracting something from
pseudoephedrine to create a different substance: “they
extract those substances”; “[d]o they extract the same
amount from this substance, as from the other sub-
stance that they bring from . . . Canada?”; “they’ll mix it
with the baking soda”; “[t]hey dissolve the medicine,
and they extract this substance from it, and they mix it
up.” The transcript attributed the last statement about
dissolving the medicine to Khattab. The dialogue from the
meeting also contained references to the resulting sub-
stance made from the extracted pseudoephedrine as a
narcotic: “the narcotic substances”; “it’s a narcotic”; “half
and half with the . . . narcotic, uh, substance.” In one
exchange, Hassan and the unidentified man compared
the resulting narcotic substance to “heroin or cocaine.”
The unidentified man then asked, “[d]o they sniff it or
inject it?” Khattab directly answered this question, “No,
they sniff it.” Khattab explained that “They’ll mix with it
the baking soda . . . [o]r with cocaine.”
  The transcript also contained an acknowledgment by
Khattab that pseudoephedrine would fetch a higher
price if sold in loose bottle form, “[Khattab:] The Canadian
stuff. . . . First, it comes loose and ready. [Hassan:] Yeah,
this one you have to make it loose by yourself. [Khattab:]
No, I can give it to them the way it is, but with a lesser
price. It’s a cheaper price.” The transcripts contained
references to the number “8,640.” And Khattab impressed
upon the other men that “the most important thing” was
for the pills to be in 60-milligram doses.
6                                               No. 07-2522

  After the government presented its case, Khattab moved
for a judgment of acquittal. Khattab’s counsel argued that
there was no testimony linking Khattab to methamphet-
amine, which meant that the government had not proven
an element of the charged offense—that Khattab knew
or had reason to believe that the pseudoephedrine he
attempted to purchase would be used to manufacture
methamphetamine. See 

The district court
denied Khattab’s motion for a judgment of acquittal,
stating that it had yet to fully review the recordings
and transcripts in evidence. The district court added
that, given its role as the finder of fact, “[the motion] is
something that involves arguing the inferences and
what inferences are properly drawn and what inferences
aren’t properly drawn from the evidence, and it just
seems to me it’s more appropriate for me to do that at
the end of the case.”
  Khattab recalled two of the government’s witnesses for
the defense case, waived his right to testify, and then
rested. After closing arguments, the district court consid-
ered the evidence and concluded that it was “just barely”
sufficient “to prove beyond a reasonable doubt that Mr.
Khattab knew not just that the people he was planning
to sell to were up to no good, but that he was going to
distribute the product to people who would use it to
make methamphetamine.” The district court explained
that although the voice identifications on the recordings
were somewhat “problematic,” the statement, “they
sniff it,” was accurately attributed to Khattab. The district
court called this statement “the most incriminating evi-
dence or potentially incriminating evidence.” The dis-
trict court also examined circumstantial evidence of
Khattab’s knowledge, such as the facts that the participants
No. 07-2522                                                7

discussing the sale used code words and wanted their
meetings kept secret. The district court reasoned that
Khattab’s behavior on May 31 further demonstrated that
he knew his actions were “illicit in some way”—“he drove
to different locations really without any apparent legiti-
mate purpose, did what appears to be countersurveil-
lance, and finalized the transaction and attempted to
transfer the product in a back alley behind a gas
station . . . .” The district court accordingly found Khattab
guilty as charged in the indictment.
  A probation officer prepared a pre-sentence investiga-
tion report (PSR), which calculated Khattab’s offense
level at 38, and his Criminal History Category at II. The
probation officer recommended a guidelines sentence of
240 months’ imprisonment, based on the PSR. The district
court canvassed several of the factors listed in 18 U.S.C.
§ 3553(a), and sentenced Khattab to a below-guidelines
sentence of 144 months’ imprisonment, finding that such
a sentence was “sufficient to reflect the seriousness of
the crime, provide just punishment, promote adequate
deterrence, and protect the public.” Khattab appealed his
conviction; neither Khattab nor the government has
appealed the sentence.


                       II. ANALYSIS
   On appeal, Khattab argues that the evidence was not
sufficient to sustain his conviction for attempting to vio-
late 21 U.S.C. § 841(c)(2). See 21 U.S.C. § 846. Section
841(c)(2) makes it illegal for any person to knowingly or
intentionally possess or distribute “a listed chemical
knowing, or having reasonable cause to believe, that the
listed chemical will be used to manufacture a con-
8                                                  No. 07-2522

trolled substance . . . .” 

Khattab concedes
that the government sufficiently proved that he attempted
to knowingly or intentionally possess pseudoephedrine,
and he instead focuses on the second element, arguing
that the government did not prove that Khattab knew
the pseudoephedrine he attempted to possess would be
used to manufacture methamphetamine—a controlled
substance. 

  “A defendant making an insufficiency of the evidence
argument faces a difficult task.” United States v. Campbell,
No. 06-3606, slip op. at 10-12 (7th Cir. July 15, 2008); see
also United States v. Angle, 

, 339 (7th Cir.
2000) (“ ‘Challenging the sufficiency of the evidence
is an uphill battle and the defendant bears a heavy bur-
den.’ ” (quoting United States v. Wallace, 

,
1003 (7th Cir. 2000))). In reviewing a challenge to the
sufficiency of the evidence, “we view all the evidence
and draw all reasonable inferences in the light most
favorable to the prosecution and uphold the verdict if any
rational trier of fact could have found the essential ele-
ments of the crime beyond a reasonable doubt.” United
States v. Gallardo, 

, 737 (7th Cir. 2007) (internal
quotation marks and citations omitted); see also United
States v. Henry, 

, 933 (7th Cir. 2005). On a
sufficiency of the evidence claim, “[w]e do not weigh the
evidence or assess the credibility of witnesses.” United
States v. Orozco-Vasquez, 

, 1106 (7th Cir.
2006); see also United States v. Farris, No. 07-1643, slip op. at
8 (7th Cir. July 9, 2008).
  There is a split among our sister circuits as to the proper
interpretation of the mens rea requirement in 21 U.S.C.
§ 841(c)(2)—one circuit believes the statute requires a
defendant’s subjective knowledge that the drugs he
No. 07-2522                                                9

possesses or distributes will be used to manufacture a
controlled substance, while at least three other circuits
parse the statute to allow conviction based upon either
subjective knowledge or an objective “cause to believe.”
Compare United States v. Truong, 

, 1289 (10th
Cir. 2005) (requiring government to prove “actual knowl-
edge, or something close to”), and United States v. Saffo,

, 1269 (10th Cir. 2000) (“The ‘reasonable
cause to believe’ standard thus comports with the sub-
jective ‘guilty mind’ or ‘guilty knowledge’ requirement
for imposing criminal liability.”), with United States v.
Galvan, 

, 957 (8th Cir. 2005) (rejecting pro-
posed jury instruction that required actual knowledge
and ignored “reasonable cause to believe” statutory
language); United States v. Kaur, 

, 1157-58 (9th
Cir. 2004) (“[C]onsistent with the text of the statute, the
instruction incorporates both subjective and objective
considerations.”); and United States v. Prather, 

, 1270 (11th Cir. 2000) (“[T]he jury thus needed
to find either that he knew the pseudoephedrine would
be used to manufacture methamphetamine or that he
had reasonable cause to believe that it would be.”). The
district court applied the more stringent standard of the
Tenth Circuit, which requires “actual knowledge, or
something close,” and concluded that the government
sufficiently proved that Khattab knew that the
pseudoephedrine he attempted to purchase would be
used to manufacture methamphetamine.
  But this case is not the proper vehicle for us to weigh
in on the circuit split regarding the proper mens rea stan-
dard for 21 U.S.C. § 841(c)(2). The evidence in the rec-
ord, construed in the light most favorable to the prosecu-
tion, supports the district court’s conclusion that Khattab
10                                             No. 07-2522

actually knew that the pseudoephedrine he attempted
to purchase from Agent Jones would be used to manu-
facture methamphetamine. And actual knowledge con-
stitutes mens rea under either approach.
  Many facts in the record support the conclusion that
Khattab actually knew the pseudoephedrine would be
used to manufacture methamphetamine. First, there are
the numerous statements taken from the transcripts that
describe the process of “extracting” a “narcotic” from
pseudoephedrine. Whether or not Khattab personally
made the statements attributed to him by the transcripts
was a matter of some contention at trial. If Khattab made
any of these statements, as the transcripts and the dis-
trict court indicated that he did, then they clearly evince
his actual knowledge that the pseudoephedrine could be
used to manufacture methamphetamine. The district
court identified the statement “they sniff it,” as the most
damaging statement correctly attributed to Khattab, and
we agree that this statement alone reveals that Khattab
was fully aware of the potentially illicit uses of
pseudoephedrine. Irrespective of who actually uttered
the other incriminating statements reported in the tran-
scripts, it is clear that they were made either directly to
Khattab, or in his presence, and they too support the
district court’s finding that Khattab knew the intended
use for the pseudoephedrine. See 

.
  Khattab insists that the statements alone do not suffi-
ciently prove the government’s case because they prove
only that Khattab knew that pseudoephedrine could be
used to make methamphetamine, not that he or the people
he planned to distribute it to would use it to make metham-
phetamine. Khattab notes that if his conviction is sus-
tained based upon his knowledge of the mere potential to
No. 07-2522                                             11

turn pseudoephedrine into a controlled substance, then
“any individual who purchased Sudafed and knew it
could be used to manufacture methamphetamine would
be guilty under the statute.” Khattab explains that the
government put forth no evidence that he was going to
manufacture methamphetamine on his own, or that he
had a connection to anyone who would receive the
pseudoephedrine and turn it into methamphetamine.
  But Khattab’s argument ignores Agent Taylor’s testi-
mony, which frames the transcripts in such a way that
reveals the criminality underlying the transaction. Taylor
testified at trial that methamphetamine producers prefer
loosely packaged pseudoephedrine to the “blister packs”
available for retail because the loose pills are easier to
process into methamphetamine. Taylor also explained
the significance of calculating the dosages of pseudo-
ephedrine tablets to ensure the proper chemistry of meth-
amphetamine. The seemingly innocuous references in the
transcripts to the number “8,640,” and Khattab’s insistence
that the pseudoephedrine pills be in 60-milligram
doses—“the most important thing”—are damaging
when analyzed through the lens of Taylor’s testimony.
Moreover, Khattab’s statement that the “blister packs”
would yield a cheaper price than the loose form sold in
Canada makes sense in light of Taylor’s explanation that
methamphetamine producers prefer loose pills because
they reduce processing costs. See 

.
  Khattab also overlooks the numerous references in the
transcripts to a nebulous third party: “they extract those
substances”; “Do they extract the same amount from this
substance, as from the other substance that they bring
from . . . Canada?”; “they’ll mix it with the baking soda”;
“[t]hey dissolve the medicine, and they extract this sub-
12                                              No. 07-2522

stance from it, and they mix it up.” These statements
provide circumstantial proof that Khattab had targets in
mind who would acquire the pseudoephedrine from him,
and that he knew precisely what his targets would do
with the pills.
  In addition to the statements in the transcripts, there
is ample circumstantial evidence that Khattab intended
to obtain pseudoephedrine that he knew would be used
to produce methamphetamine. See United States v. Bailey,

, 735 (7th Cir. 2005) (“In proving its case, the
government can rely on both direct and circumstantial
evidence.”). First, there is Khattab’s conduct prior to the
May 31 DEA sting, which the district court explained
indicated Khattab’s knowledge that the transaction
was “illicit in some way.” Khattab grew apprehensive
about potential police presence and cancelled the initial
meeting. He then rescheduled it and attempted to execute
the sale in a back alley behind a gas station after he “drove
to different locations really without any apparent legiti-
mate purpose” and “did what appears to be counter-
surveillance” prior to finalizing this meeting. And there
is also circumstantial evidence derived from the
economics of the transaction. According to Taylor,
Khattab could not have had a legitimate use for at-
tempting to possess the large volume of pseudoephedrine
because purchasing such an amount violated DEA regula-
tions. It also appears there is no illicit use Khattab
could have had for enough pseudoephedrine to medically
treat 2,000 people for an entire week, other than the
manufacture of methamphetamine—two law enforce-
ment officers testified that they knew of no other black-
market use for pseudoephedrine. We doubt that Khattab
would have purchased such a vast supply of
No. 07-2522                                           13

pseudoephedrine for double the retail price without an
accompanying demand. The only plausibly rational
demand consistent with Khattab’s purchase of 57,600
loose pseudoephedrine pills at an inflated price is the
production of methamphetamine.
  Given the evidence, we do not believe that the gov-
ernment “just barely” met its burden of proof. A rational
fact finder could have easily found that the government
proved that Khattab knew the pseudoephedrine would
be manufactured into methamphetamine.


                   III. CONCLUSION
 We AFFIRM the district court’s judgment of conviction.




                   USCA-02-C-0072—8-5-08