FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 07-50195
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-06-00019-DSF-1
TYRONE ALAN GANOE,
                                              OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
          for the Central District of California
        Dale S. Fischer, District Judge, Presiding

                   Argued and Submitted
            July 14, 2008—Pasadena, California

                   Filed August 15, 2008

  Before: Barry G. Silverman, Johnnie B. Rawlinson, and
           Milan D. Smith, Jr., Circuit Judges.

               Opinion by Judge Silverman




                           10733
10736               UNITED STATES v. GANOE
                          COUNSEL

Karen L. Landau, Oakland, California, for the defendant-
appellant.

Thomas P. O’Brien, Christine C. Ewell, and Mark C. Krause,
United States Attorney’s Office, Los Angeles, California, for
the plaintiff-appellee.


                          OPINION

SILVERMAN, Circuit Judge:

    In this appeal from convictions for receipt and possession
of child pornography, we hold today that the district court
acted within its discretion in allowing the jury to briefly view
a carefully limited number of images that were the subjects of
the charged offenses. Ganoe’s offer to stipulate that anyone
viewing the images would have known that they met the legal
definition of child pornography did not render the evidence
impermissible, because he refused to also stipulate that the
titles of the computer files alone were enough to import
knowledge of what they were. We also affirm the denial of
Ganoe’s motion to suppress evidence obtained by a federal
agent using peer-to-peer software. Ganoe installed and used
file-sharing software on his computer; he knew or should
have known that the folder into which he downloaded files
was accessible to others on the peer-to-peer network. We hold
that Ganoe lacked an objectively reasonable expectation of
privacy in those files. Lastly, we find no error or abuse of dis-
cretion in the district court’s calculation of Ganoe’s sentence.

         I.   FACTUAL AND PROCEDURAL BACKGROUND

The investigation

  On January 5, 2004, Immigration and Customs Enforce-
ment Special Agent Ken Rochford was using LimeWire to
                    UNITED STATES v. GANOE                10737
locate people using file-sharing programs to trade child por-
nography. LimeWire is a file-sharing program that can be
downloaded from the internet free of charge; it allows users
to search for and share with one another various types of files,
including movies and pictures, on the computers of other per-
sons with LimeWire. Once a user downloads the program
onto his computer, the user can click on an icon that connects
his computer to others on the network. Users can input search
terms and receive a list of responsive files available on other
computers connected to the network.

   Upon observing a file entitled “Baby J Compilation,”
Rochford downloaded and viewed the movie, confirming that
it depicted an adult having sexual intercourse with a very
young girl. (The computer forensics expert testified that
“BabyJ” is a common term in the world of child pornography,
referring to “a specific victim of child exploitation” depicted
in a series of pictures and movies.) Rochford used
LimeWire’s “Browse Host” feature to view all of the files
being shared by a particular “Host,” thereby discovering four
additional file titles that suggested similar content. Rochford
downloaded and viewed these files, observing that they too
contained footage of children engaged in sexually explicit
conduct. Rochford determined that the downloads originated
from a computer with a particular IP address, and that the IP
address was assigned to Tyrone Ganoe, located at a specified
residence in Norwalk, CA.

   Agents obtained a search warrant for that address, which
was executed on March 9, 2004. Tyrone Ganoe arrived at the
residence while the agents were engaged in the search. He
spoke with Agent Margaret Condon, who advised him that he
was not under arrest but that she would like to ask him a few
questions. Ganoe agreed, confirming that he lived at the house
with his mother Josephine and his sister Yvette. Condon
asked Ganoe if he knew why the agents were there, and he
said that he did; he explained that he had been using
LimeWire to download music and had inadvertently down-
10738               UNITED STATES v. GANOE
loaded child pornography. He stated that the “bad stuff” could
be found in the “z” folder on the iMac. Upon examination, the
“z” folder was found to contain 72 image and movie files sus-
pected to be child pornography.

   The day after the search of Ganoe’s residence, Agent Con-
don called Ganoe on his cell phone to inform him that he
could retrieve some of the items taken during the search.
Ganoe volunteered that he was seeking counseling for his
“problem.” Agent Condon asked him what he meant, and he
stated that he was referring to his habit of viewing child por-
nography.

The indictment

   The first superseding indictment charged Ganoe with three
counts of knowingly receiving child pornography and one
count of knowingly possessing child pornography, all in vio-
lation of 18 U.S.C. § 2252A. The first count alleged that
Ganoe had received a digital image entitled “babyj Cock in
Her.mpg.” on or about November 22, 2003. The second count
alleged that Ganoe had received a digital image entitled
“BabyJ-ButtHump.mpg” on or about December 5, 2003. The
third count alleged that Ganoe had received a digital image
entitled “BabyJ-Teddy.mpg” on or about January 21, 2004.
The fourth count listed 65 different image titles and alleged
that Ganoe had possessed at least one on or about March 9,
2004.

Pre-trial motions

   Prior to trial, Ganoe moved to exclude the images at issue
on the grounds that they were inflammatory and unduly preju-
dicial, offering to stipulate that “the images seized on the
computer at the Ganoe family home are child pornography
within the meaning of the statute,” and that any reasonable
person viewing the images would have known that they were
child pornography. The government sought more, asking the
                    UNITED STATES v. GANOE                 10739
defense to stipulate that Ganoe himself “had knowledge that
they were, in fact, illegal.” Defense counsel refused and the
court directed the attorneys to “attempt to agree on a stipula-
tion that might make the introduction of such images unneces-
sary. Alternatively, counsel should attempt to agree to a
representative selection of still photographs and short portions
of video clips to be introduced into evidence after the Govern-
ment presents evidence sufficient for the jury to conclude that
defendant saw the images.”

   At a subsequent hearing on the motion to exclude the
images, the district court reviewed the selection of images
proposed by the prosecution for viewing by the jury. Defense
counsel reiterated that the images were highly inflammatory
and argued further that the sequence was very repetitive;
defense counsel again asserted that the proffered stipulation
“makes the whole issue moot.” The district court directed the
government to select ten images to show to the jury. The dis-
trict court also directed the government to investigate whether
technology was available to distort the faces of the children
depicted in the images. On January 5, 2007, the parties stipu-
lated that the images specified in the indictment were trans-
ported in interstate commerce and depicted actual minors
engaging in sexually explicit conduct. Despite defense coun-
sel’s earlier proffer, this stipulation did not include the provi-
sion that any reasonable person would have known that the
images were child pornography.

   In its written order the district court elaborated on its rea-
soning. Noting that the government was obligated to prove
that Ganoe knew the downloaded images were child pornog-
raphy and that Ganoe would not so stipulate, the district court
reasoned that “the images must be produced so that the jury
can determine whether a reasonable person would know of
the nature of the images.”

  The next day, immediately prior to the beginning of trial,
defense counsel made another attempt to have the images
10740               UNITED STATES v. GANOE
excluded, offering to stipulate further that “[a]nyone who sees
those images for one second knows that they are child por-
nography.”

   The following day the government offered to accept a stip-
ulation that anyone who read the file titles would have known
they were downloading child pornography. The defense
refused, rejecting the proposition that merely selecting a file
for download on the basis of a title was sufficient to constitute
knowledge in the absence of a showing that the images were
actually viewed. The district court ruled that “although the
images obviously are prejudicial, in the context of this case,
they are extremely probative. They have been limited. We
have inquired of the jury concerning their ability to view
those images. We have an instruction that I will give them
that the Government proposed, and I am going to allow the
images to be shown.”

   Also prior to trial, the defense moved to suppress the evi-
dence obtained from Ganoe’s computer during the execution
of the search warrant on the grounds that Rochford’s initial
search was illegal. The district court denied the motion, rea-
soning that Ganoe did not have a reasonable expectation of
privacy in a computer on to which he had loaded the file-
sharing program. Rejecting Ganoe’s claim that he wasn’t
“computer-savvy” enough to have used the disabling feature,
the district court concluded that “[h]e knew or should have
known that the software might allow others to access his com-
puter.”

   Ganoe also sought to exclude evidence of the firearms
seized at the Ganoe family, including evidence that some of
the weapons were not legal to possess. The district court ruled
that the evidence was not inextricably intertwined with the
charged conduct, and that the admissibility of the evidence
would depend on the evidence introduced by Ganoe; the dis-
trict court instructed that the government was not to introduce
the firearm evidence without seeking permission.
                   UNITED STATES v. GANOE                10741
The prosecution’s case-in-chief

   At trial Agent Rochford testified about his experience in
investigating child pornography offenses and explained how
he had downloaded files containing child pornography from
an IP address later determined to be associated with Ganoe’s
computer. Agent Condon testified about the search that was
conducted at the Ganoe residence, including Ganoe’s state-
ments acknowledging his possession of child pornography,
and her subsequent telephone conversation with Ganoe in
which he volunteered that he was receiving counseling for his
“problem.” Bruce Pixley, the government’s computer foren-
sics expert, explained how peer-to-peer programs such as
LimeWire work and testified about his examination of
Ganoe’s computer. Pixley said that he found 72 pictures and
videos depicting child pornography in a subfolder entitled
“z,” located within the iTunes folder. Ten of these images,
each lasting only a few seconds, were shown to the jury one
time. In addition, before the images were played, the district
court gave a cautionary instruction that the images were being
shown “only to assist you in determining whether the govern-
ment has met its burden to prove the defendant guilty of all
of the elements of the charges against him.” The district court
cautioned the jurors not to “allow any feelings that you may
have regarding these images to affect this determination in
any way,” and reminded the jurors of their oath to be fair and
impartial to both sides.

The defense

   The defense called Ganoe’s sister Yvette, her boyfriend
Joseph DiLello, and her friend Rhonda Poston to testify that
a man named Ray Rodriguez lived at the Ganoe family home
for several months during the fall of 2003 and the winter of
2004, but vanished after Yvette told him that federal agents
had seized the computer from the music room. DiLello testi-
fied that he had personally observed Rodriguez search for and
download child pornography on to the computer, and that he
10742              UNITED STATES v. GANOE
had never seen Ganoe on the computer. The defense also cal-
led a number of witnesses to provide alibis for Ganoe on the
dates and times during which the child pornography was
downloaded.

Prosecution’s rebuttal case

   In rebuttal the prosecution called Coraly Serrano, Ganoe’s
ex-girlfriend. Serrano testified that Ganoe asked her to assist
him in the fabrication of an alibi and that the Ganoe family
had invented the existence of Ray Rodriguez. At the conclu-
sion of the direct examination, defense counsel asked to defer
cross-examination, stating that Serrano’s testimony was
“nothing we have ever heard before” and that the defense
needed “an opportunity to look into it further so that we can
address the witness appropriately.” The court denied the
request, and Serrano was cross-examined about her feelings
of anger towards Ganoe as a result of their break-up. During
the cross-examination of Serrano, defense counsel renewed
the request for a continuance to allow for additional prepara-
tion, which the district court denied.

   The government also recalled Pixley, who testified that
whoever was using the computer at the time the child pornog-
raphy was downloaded had also accessed Ganoe’s PayPal
account, used Ganoe’s American Express card, logged onto
his email account, and sent emails to people associated with
Ganoe, suggesting that it must have been Ganoe himself.

Defense surrebuttal

   After the conclusion of the prosecution’s case in rebuttal,
defense counsel sought to present surrebuttal, asking to recall
Yvette, DiLello, and Poston to address the accusation of fabri-
cation. The district court agreed to “very limited” questioning
to allow these witnesses to address the allegations that they
had fabricated the existence of Rodriguez. Joseph DiLello tes-
tified that a list of passwords and user names for various
                   UNITED STATES v. GANOE                10743
password-protected websites was kept next to the computer,
suggesting that anyone using the computer could have
accessed these sites. DiLello was cross-examined about the
password list and other aspects of his testimony, and was then
excused by the judge, at which point defense counsel sought
to ask “one follow-up question.” The district court refused; at
sidebar, defense counsel explained that she wanted DiLello to
identify the paper containing the password list and to have the
list introduced into evidence. The district court denied the
request on the grounds that counsel had the paper during
direct examination.

   Defense counsel also sought to call Coraly Serrano back as
an adverse witness to probe more extensively Serrano’s “bi-
ases and motives.” The district court viewed this proposed
line of questioning as outside the purview of proper surrebut-
tal, noting that the defense had been “well aware” of Serra-
no’s existence prior to her appearance on the prosecution’s
witness list. After an extended colloquy regarding the scope
of questioning that would be allowed, Serrano took the stand
and was asked about her relationship with the Ganoe family,
her blog postings about Ganoe and his arrest, and a number
of other topics. Defense counsel began to question Serrano
about her employment history, triggering a relevance objec-
tion from the prosecution. At sidebar, defense counsel
explained that she was preparing to ask the witness about
prior instances of dishonesty, specifically that Serrano had
undergone breast augmentation surgery and charged it to the
credit card of her former employer; similarly, that while
working for a finance company Serrano had purchased shoes
using stolen credit card numbers from the company’s custom-
ers. Commenting that “[i]t doesn’t really have anything to do
with this case,” the district court ruled that such questioning
would not be allowed.

Verdict, sentencing, and appeal

  Ganoe was convicted on counts one, two, and four, and was
acquitted on count three. He was sentenced to 96 months in
10744               UNITED STATES v. GANOE
prison, a $15,000 fine, and five years of supervised release.
He timely appealed and raises the following claims of error.

                        II.   DISCUSSION

A.   The district court did not abuse its discretion in
     allowing the jury to view a carefully tailored selection
     of the child pornography images charged in the
     indictment.

   Ganoe contends that the images of child pornography
shown to the jury were unfairly prejudicial, lacking in proba-
tive value, and should have been excluded under Federal Rule
of Evidence 403. Reviewing for abuse of discretion, see
United States v. Merino-Balderrama, 

, 761 (9th
Cir. 1998), we find none.

   [1] Federal rule of Evidence 403 provides that “evidence
may be excluded if its probative value is substantially out-
weighed by the danger of unfair prejudice.” As to the danger
of unfair prejudice, Ganoe observes that the images at issue
here were “unusually inflammatory,” depicting children as
young as four years old being subjected to anal and vaginal
intercourse with adult males. Ganoe asserts that the probative
value of the images was eliminated by his offer to stipulate
that the images represented actual children engaged in sexual
conduct and that anyone seeing the images even for a moment
would know that they were child pornography. We disagree.

   [2] To begin, Ganoe’s proffered stipulation was incom-
plete, because he refused to stipulate that the file titles alone
would convey to a reasonable user that the files contained
child pornography; moreover, some aspects of his defense
suggested that one could mistakenly download such files
thinking they were adult pornography or otherwise legal. This
left the government with the obligation to prove that Ganoe
was aware of the content of the images. As to this burden
Ganoe’s proffered stipulation was silent, whereas the images
                    UNITED STATES v. GANOE                 10745
— in conjunction with the rest of the forensic evidence —
said a great deal. Of the child pornography files charged in the
indictment — including the subset shown to the jury — many
had titles that were excruciatingly suggestive of the content
(“babyj Cock in Her”), while other titles could arguably be
said to be ambiguous as to either the depiction of sexual con-
duct (“BabyJ Teddy”) or the age of participants (“Vicky69”).
Every single child pornography file found on Ganoe’s com-
puter, descriptively titled or not, was placed in the “z” folder,
and the “z” folder contained nothing but child pornography.
Pixley explained that this categorization had to have been
achieved manually, by “user intervention” rather than by vir-
tue of a default setting.

   [3] The fact that the vast majority of the titles accurately
described the nature of the corresponding image was relevant
to rebut the defense’s suggestion that one could download the
files without intending to obtain child pornography. The fact
that even those files that were not explicitly titled also turned
out to contain child pornography and were likewise placed in
the “z” folder strongly suggests that the images had to have
been viewed in order to be categorized. The jury had to see
the images to be able to draw these conclusions. Thus the
images themselves, published to the jury as part of the gov-
ernment’s detailed and comprehensive forensic evidence
regarding the downloading, viewing, categorizing, and storing
of the files, were highly probative of the state of mind with
which the files were received and possessed. Seen in this con-
text we think it plain that Ganoe’s proffered stipulation sim-
ply did not “supply evidentiary value at least equivalent to
what the Government’s own evidence carried.” See Old Chief
v. United States, 

, 186 (1997).

   [4] In weighing the probative value of the images against
the danger of unfair prejudice, we emphasize that each of the
clips was derived from files charged in the indictment; the
images shown to the jury were thus not extrinsic to the crime
charged “but rather a part of the actual pornography pos-
10746               UNITED STATES v. GANOE
sessed.” See United States v. Dodds, 

, 898 (11th
Cir. 2003). Even more importantly, for every image shown to
the jury there was forensic evidence that the files had actually
been opened and viewed after downloading. This is what
makes this case distinguishable from United States v. Merino-
Balderrama, in which we reversed a conviction for possession
of child pornography where the district court erroneously
allowed the government to show excerpts from child pornog-
raphy films found in the trunk of the defendant’s car. 

. Seeking to keep the films from the jury’s view,
the defendant had offered to stipulate that the films were child
pornography and had traveled in interstate commerce. 

In Merino, however, it had been undisputed that the
defendant never saw the actual films — only the box covers,
which depicted images that turned out to be stills taken from
the movies within. This is a crucial distinction, because in
conducting the Rule 403 analysis, we emphasized that the
films, which had not been viewed by the defendant, were con-
siderably less probative to scienter than the box covers, which
the defendant had seen. 

In this case, the images
themselves were probative of scienter in a way that was sim-
ply absent in Merino-Balderrama.

   [5] As the First Circuit recently observed, “The trial judge’s
job is to avoid unfair prejudice. The court is not required to
scrub the trial clean of all evidence that may have an emo-
tional impact.” United States v. Morales-Aldahondo, 

, 120 (1st Cir. 2008) (affirming the admission of 12 photo-
graphs and 10 video clips depicting child pornography). Here
the record reflects that the district court used just about every
tool at its disposal to minimize the inflammatory nature of the
images. The district court limited the government to ten clips,
each one lasting a few seconds, with a total duration of under
one minute. The images were played only once. The district
court gave two cautionary instructions, directing the jury to
view the images in an impartial and unbiased manner. All of
this was after careful voir dire on the subject during jury
selection. Indeed, the jury’s verdict demonstrates quite com-
                   UNITED STATES v. GANOE                10747
pellingly that the district court succeeded in avoiding unfair
prejudice. The jury acquitted Ganoe on count three of the
superseding indictment that charged him with receiving a dig-
ital file entitled “BabyJ-Teddy.mpg,” in spite of the fact that
a portion of that very film was shown to the jury. The district
court properly exercised its discretion in connection with the
admission of the images.

B.   Any abuse of discretion in the district court’s
     limitation on the questioning of Coraly Serrano was
     harmless.

   [6] Ganoe next asserts that his Sixth Amendment right to
confrontation was violated by the district court’s refusal to
allow him to question Serrano during surrebuttal about
whether she had used the credit cards of her former employer
and former customers for personal gain. Because Serrano had
already been subjected to robust cross-examination about her
biases and motivations to lie and because it arises in the con-
text of surrebuttal, we view this ruling as a limitation on the
scope of questioning regarding Serrano’s credibility, and we
therefore review the ruling for abuse of discretion. See United
States v. Larson, 

, 1101-02 (9th Cir. 2007) (en
banc).

   [7] The next step is to consider whether the ruling violated
Ganoe’s right “to be confronted with the witnesses against
him,” which includes “the right of effective cross-
examination.” 

We have identified three factors to
consider in determining whether a defendant’s right to effec-
tive cross-examination was violated: “(1) whether the
excluded evidence was relevant; (2) whether there were other
legitimate interests outweighing the defendant’s interest in
presenting the evidence; and (3) whether the exclusion of evi-
dence left the jury with sufficient information to assess the
credibility of the witness.” 

We note that we con-
sider the excluded evidence to be relevant, as it tends to
reflect Serrano’s character for truthfulness and thus sheds
10748                 UNITED STATES v. GANOE
light on the truthfulness of her testimony. See 1 MCCORMICK
ON EVIDENCE 150 (5th ed. 1999) (“The fact that the witness
previously engaged in deception tends to show the witness
has a character trait for untruthfulness, and in turn the exis-
tence of that character trait at least slightly increases the prob-
ability that the witness lied during his testimony.”). Because
the proposed line of questioning was offered as evidence of
Serrano’s character for untruthfulness, we do not quite under-
stand the district court’s comment that “it doesn’t really have
anything to do with this case.”1 As to whether the jury had
sufficient information to assess Serrano’s credibility, we note
that the jury was presented with voluminous evidence that
Serrano had made threats against Ganoe, was still very angry
with him over their break-up, and had made prior statements
inconsistent with her testimony. Ultimately, however, we
need not determine whether this was adequate to satisfy the
Sixth Amendment: even if Ganoe did suffer a Confrontation
Clause violation, we conclude that any error was harmless
beyond a reasonable doubt. See 

.
Although the trial was certainly hard fought, the evidence of
Ganoe’s guilt was overwhelming. Ganoe made statements to
Condon acknowledging that there were child pornography
files on his computer and explaining that he had placed all the
“bad stuff” in the “z” folder. During the search he character-
ized the downloading as inadvertent, but the next day he
informed her that he was seeking counseling for his “prob-
lem.” The government also introduced substantial forensic
evidence to demonstrate that it was Ganoe who knowingly
received or possessed child pornography, including evidence
that most of the files were downloaded while Ganoe accessed
password-protected websites such as his online bank account;
that all of the files had been opened and viewed after down-
loading; and that the categorized placement of the child por-
  1
   The government suggested during oral argument that the district
court’s ruling can be understood as a determination that defense counsel
sought to impeach Serrano on a collateral matter and without sufficient
factual foundation.
                    UNITED STATES v. GANOE                 10749
nography files into the “z” folder would have to have been
done manually by the user. In light of this evidence, we are
unable to entertain a reasonable doubt that the outcome of the
trial would have been different had Ganoe been permitted to
ask Serrano about her misuse of employer and customer credit
cards.

C.   The district court did not abuse its discretion in
     excluding the list of passwords.

   The defense recalled Joseph DiLello in its surrebuttal case
to counter forensic expert Pixley’s testimony that whoever
was using the computer at the time the child pornography was
downloaded also accessed Ganoe’s PayPal account, used
Ganoe’s American Express card, logged onto his email
account, and sent emails to people associated with Ganoe.
During his surrebuttal testimony, DiLello explained that there
was a list of usernames and passwords “kept right next to the
iMac computer.” After he was cross-examined, defense coun-
sel sought an opportunity to have DiLello identify the pass-
word list, and the district court refused. Ganoe challenges the
district court’s ruling, a decision reviewed for abuse of discre-
tion. See United States v. Blackstone, 

, 1145 (9th
Cir. 1995).

   [8] Ganoe’s own argument reveals why there was no abuse
of discretion. In explaining why the list should have been
admitted, he states that “DiLello would have testified the list
was visible and physically close to the iMac computer and
was used to access the internet accounts by persons other than
Tyrone Ganoe.” The problem is that DiLello did testify that
the password list “was kept right next to the iMac computer.”
When asked whether anyone using the computer could have
logged on to the password-protected accounts by using the
passwords on the list, DiLello answered “[i]f they so wished
they could, yes.” This was made perfectly clear without the
paper upon which the passwords were written. The actual list
may have added a measure of credibility to DiLello’s testi-
10750                UNITED STATES v. GANOE
mony in the jury’s eyes, but it was cumulative, and the district
court did not abuse its discretion by excluding it.

D.   The district court did not abuse its discretion in
     admitting evidence that firearms were seized from
     Ganoe’s home.

   Ganoe objects to the admission of evidence that numerous
firearms, including assault rifles, were seized from his home
during the execution of the search warrant. Agent Murphy,
who assisted Agent Condon, testified that during the search
Ganoe was asked if there were firearms in the home. Ganoe
directed the agents to the “music room” attached to the garage
— the same room in which the computer was located. Mur-
phy testified that within the room there were two separate
cases in which assault rifles were secured, and that agents also
found a “substantial number” of “legal-to-possess” hunting
rifles, shotguns, and possibly antique weapons throughout the
rest of the house.

   [9] Ganoe contends that such evidence was prejudicial and
“irrelevant to charges that a defendant, using a computer,
received or possessed images of child pornography.” The dis-
trict court did not abuse its discretion in ruling to the contrary.
The evidence was relevant to demonstrate Ganoe’s ownership
and control over the music room and the items found in it. We
reject Ganoe’s contention that the firearms were cumulative
for that purpose due to previous testimony that he kept his
guitars and their cases in the music room. Because assault
rifles are dangerous and heavily regulated, it is unlikely that
visitors would have unfettered access to the room in which
they were kept. Furthermore, the district court instructed the
jury that evidence concerning the firearms could be consid-
ered “only as it bears on the defendant’s knowledge, identity,
or absence of mistake or accident in the commission of the
charged crimes,” and not for any other purpose. The district
court did not abuse its discretion by allowing the govern-
                    UNITED STATES v. GANOE                 10751
ment’s introduction of firearms evidence to rebut the Ray
Rodriguez defense.

E.   There is no cumulative error.

   Ganoe urges us to conclude that the cumulative effect of
the four evidentiary rulings discussed above deprived him of
a fair trial. As we have explained, we discern no error in the
district court’s decisions regarding the child pornography, the
password list, and the firearms evidence. As we have also
explained, any error in the district court’s refusal to allow Ser-
rano to be questioned about prior instances of dishonesty was
harmless beyond a reasonable doubt in light of the over-
whelming evidence of Ganoe’s guilt. There is no cumulative
error warranting reversal. Cf. United States v. Wallace, 

, 1475 (9th Cir. 1988).

F.   The district court correctly denied the motion to
     suppress evidence obtained from Ganoe’s computer.

   [10] Ganoe asserts that when Agent Rochford used
LimeWire to access the child pornography files on his com-
puter, Rochford conducted a warrantless search that was ille-
gal under the Fourth Amendment. The district court denied
Ganoe’s motion to suppress evidence obtained from Roch-
ford’s search on the grounds that having installed file sharing
software on his computer, Ganoe “knew or should have
known that the software might allow others to access his com-
puter” and thus lacked a reasonable expectation of privacy in
the files stored on his computer. We agree and affirm the
denial of the motion to suppress.

   Although as a general matter an individual has an objec-
tively reasonable expectation of privacy in his personal com-
puter, see United States v. Heckenkamp, 

, 1146
(9th Cir. 2007), we fail to see how this expectation can sur-
vive Ganoe’s decision to install and use file-sharing software,
thereby opening his computer to anyone else with the same
10752                 UNITED STATES v. GANOE
freely available program. The crux of Ganoe’s argument is
that he simply did not know that others would be able to
access files stored on his own computer. But he knew he had
file-sharing software on his computer; indeed, he admitted
that he used it — he says to get music. Moreover, he was
explicitly warned before completing the installation that the
folder into which files are downloaded would be shared with
other users in the peer-to-peer network. Ganoe thus opened up
his download folder to the world, including Agent Rochford.
To argue that Ganoe lacked the technical savvy or good sense
to configure LimeWire to prevent access to his pornography
files is like saying that he did not know enough to close his
drapes. Having failed to demonstrate an expectation of pri-
vacy that society is prepared to accept as reasonable, Ganoe
cannot invoke the protections of the Fourth Amendment. See
United States v. Bautista, 

, 589 (9th Cir. 2004).

G.    Sentencing contentions

   In conducting its sentencing analysis the district court used
a base offense level of 17, pursuant to the 2003 version of
U.S.S.G. § 2G2.2 . This sentencing guideline applies to “Traf-
ficking in Material Involving the Sexual Exploitation of a
Minor; Receiving, Transporting, Shipping, or Advertising
Material Involving the Sexual Exploitation of a Minor; Pos-
sessing Material Involving the Sexual Exploitation of a Minor
with Intent to Traffic.” Ganoe asserts that the district court
should have applied U.S.S.G. § 2G2.4 , which is titled “Pos-
session of Materials Depicting a Minor Engaged in Sexually
Explicit Conduct” and provides a base offense level of 15.
The essence of Ganoe’s position is that his offense was pos-
sessory in nature, lacking the intent or conduct associated
with trafficking.2
  2
  This view was shared by the probation officer, who calculated the rec-
ommended sentence using U.S.S.G. § 2G2.4.
                    UNITED STATES v. GANOE                 10753
   [11] The problem with this contention is that the statutory
index for the 2003 sentencing guidelines, under which Ganoe
was sentenced, allows the district court to apply either
§ 2G2.2 or § 2G2.4 to violations of 18 U.S.C. § 2252A. The
index instructs the district court to use the guideline “most
appropriate for the offense conduct charged in the count of
which the defendant was convicted.” The district court did so,
beginning with the observation that both the statute and the
guidelines present two categories of conduct — simple pos-
session and “everything else.” Noting that Ganoe was con-
victed of two counts of receiving child pornography, the
district court determined that this took him out of the realm
of simple possession and into the world of § 2G2.2 which
applies to receiving and a host of other activities, even though
“[s]imple receiving is likely the least serious of these various
charges.” The district court did not err in its interpretation of
the guidelines or abuse its discretion in applying § 2G2.2 to
Ganoe’s conduct. See United States v. Rising Sun, 

, 993 (9th Cir. 2008).

   Nor are we able to identify clear error in the district court’s
imposition of a $15,000 fine, as it is the defendant’s burden
to establish that he is unable to pay. See United States v. Rear-
don, 

, 617 (9th Cir. 2003). That there may be
uncertainty in the record about Ganoe’s ability to pay reflects
that Ganoe failed to carry that burden.

  The judgment of the district court is therefore AFFIRMED.