                 FOR PUBLICATION
 UNITED STATES COURT OF APPEALS
      FOR THE NINTH CIRCUIT

UNITED STATES OF AMERICA,                  No. 05-30397
                Plaintiff-Appellee,
               v.                            D.C. No.
                                          CR-04-05525-FDB
JOEL BATTERSHELL,
                                             OPINION
             Defendant-Appellant.
                                      
       Appeal from the United States District Court
          for the Western District of Washington
       Franklin D. Burgess, District Judge, Presiding

                  Argued and Submitted
            June 5, 2006—Seattle, Washington

                   Filed August 10, 2006

     Before: Robert R. Beezer, Richard C. Tallman, and
               Jay S. Bybee, Circuit Judges.

                Opinion by Judge Tallman




                           9259
9262           UNITED STATES v. BATTERSHELL


                       COUNSEL

Colin Fieman, Assistant Federal Public Defender, Tacoma,
Washington, for the defendant-appellant.

John McKay, United States Attorney, Seattle, Washington,
for the plaintiff-appellee.
                 UNITED STATES v. BATTERSHELL              9263
                          OPINION

TALLMAN, Circuit Judge:

   We are asked to determine whether a search warrant appli-
cation describing allegedly illegal photos contained on a com-
puter was sufficient to establish probable cause to search the
computer when the application did not include copies of the
offending images.

   Vancouver, Washington, police seized Joel Battershell’s
computer after responding to a call from Battershell’s girl-
friend and her sister that they had found child pornography on
it. Four months later, a police forensic detective trained in
retrieving computer evidence applied for a search warrant to
examine its contents. The warrant application signed by the
forensic investigator did not include copies of the digital pho-
tographs taken by patrol officers of two pictures the officers
had seen on the computer when they took the complaint. The
police report appended to the warrant application, however,
recited the women’s original complaint that the computer con-
tained photos of “kids having sex” as well as the officers’
description of the two photos they had viewed.

   A Clark County, Washington, district court judge found the
warrant application sufficient to establish probable cause that
Battershell’s computer contained images of minors engaged
in sexually explicit activity. Following the search, Battershell
was indicted for possession of more than 2,500 prohibited
images located on his computer and he moved to suppress the
evidence seized pursuant to the warrant on grounds that the
warrant was invalid. The United States district judge denied
his motion and this appeal followed a conditional plea of
guilty. We affirm.

                               I

   The following facts are drawn from the evidence presented
at the suppression hearing before the federal district court and
on the court’s factual findings in support of its ruling.
9264             UNITED STATES v. BATTERSHELL
   On April 6, 2004, Vancouver Police Officer Steven Lobdell
responded to a call from Grace Smith, Battershell’s girlfriend,
reporting that she and her sister had found pictures of minors
engaged in sexual activity on Battershell’s computer. Smith
had been living at Battershell’s home for three months and
was given permission to use the computer so that she and her
sister could look for jobs online. Smith and her sister told
Officer Lobdell that while using Battershell’s computer they
had opened a file entitled “Potter,” in which they saw pictures
of “kids having sex.” Smith and her sister also told the officer
that Battershell was the only Windows user.

   Smith and her sister opened the “Potter” folder and gave
Officer Lobdell permission to view several small thumbnail
photos. It was clear that some of the photos showed undressed
people, but Officer Lobdell enlarged two pictures to see more
details. According to Officer Lobdell’s report, which was
included in the warrant application, the first picture showed
“a young female (8-10 YOA) naked in a bathtub. The second
picture showed another young female having sexual inter-
course with an adult male. This confirmed that the pictures
were illegal to obtain.”

   Officer Lobdell retrieved a digital camera from his police
car and “took photos of [the two pictures he had enlarged] to
document should there be a computer problem.” At this time
Officer Jennings arrived at the home and “also observed the
photos to confirm they were on the computer.” The officers
then turned the computer off and seized it.

   Officer Lobdell called Vancouver police computer foren-
sics investigator Maggi Holbrook for advice on how to handle
the computer. She told him to place it into evidence and said
that she would later obtain a warrant to search the computer
for pictures. On August 28, 2004, after obtaining the search
warrant from a Washington state court judge, Holbrook con-
ducted a forensic examination of Battershell’s computer and
uncovered 2,731 images depicting the sexual abuse and
                 UNITED STATES v. BATTERSHELL              9265
exploitation of children. These images were found on the hard
drive in the “Potter” folder and on a compact disk taken from
the computer.

   After Battershell was indicted by a federal grand jury, and
following an evidentiary hearing, the district court denied
Battershell’s motion to suppress the evidence, ruling that the
warrant application established probable case. Battershell and
the government then entered into a conditional plea agreement
pursuant to Rule 11(c) of the Federal Rules of Criminal Pro-
cedure for violation of possessing visual depictions of minors
engaged in sexually explicit conduct. 18 U.S.C. §§ 2252A(a)
(5)(B), (b)(2), and 2256 (2000 & Supp. 2005). The district
court sentenced Battershell to thirty-six months of imprison-
ment. This timely appeal followed.

                               II

                               A

   A district court’s denial of a motion to suppress evidence
is reviewed de novo. United States v. Bynum, 362 F.3d 574,
578 (9th Cir. 2004). The factual findings underlying the
denial of the motion are reviewed for clear error. Id.

   The governing legal principles are clear and easy to apply
in this case. We want to encourage police officers to obtain
search warrants and we rely on the judgment of neutral and
detached magistrates to determine whether probable cause
exists to support their issuance. “A magistrate’s determination
of probable cause should be paid great deference by review-
ing courts,” Illinois v. Gates, 462 U.S. 213, 236 (1983) (inter-
nal quotation marks omitted), and can only be reversed if it
is clearly erroneous. United States v. Moreno, 758 F.2d 425,
427 (9th Cir. 1985); see also United States v. Leon, 468 U.S.
897, 914 (1984) (“Reasonable minds frequently may differ on
the question whether a particular affidavit establishes proba-
ble cause, and we have thus concluded that the preference for
9266               UNITED STATES v. BATTERSHELL
warrants is most appropriately effectuated by according great
deference to a magistrate’s determination.” (internal quotation
marks omitted)).

   In Gates, the Supreme Court abandoned the old reliability
and corroboration tests of Spinelli v. United States, 393 U.S.
410 (1969), and Aguilar v. Texas, 378 U.S. 108 (1964), and
“reaffirm[ed] the totality-of-the-circumstances analysis that
traditionally has informed probable-cause determinations.”
462 U.S. at 238. The Court held that “[t]he task of the issuing
magistrate is simply to make a practical, common-sense deci-
sion whether, given all the circumstances set forth in the affi-
davit before him . . . there is a fair probability that contraband
or evidence of a crime will be found in a particular place.”
Gates, 462 U.S. at 238 (emphasis added); see also Walden v.
Carmack, 156 F.3d 861, 870 (8th Cir. 1998) (“[Search war-
rant a]pplications and affidavits should be read with common
sense and not in a grudging, hyper technical fashion.”). Our
role as “a reviewing court is simply to ensure that the magis-
trate had a substantial basis for concluding that probable
cause existed.” Gates, 462 U.S. at 238-39 (internal quotation
marks and alteration omitted). Indeed, we recently clarified en
banc that “[w]e are not in a position to flyspeck the affidavit
through de novo review.” United States v. Gourde, 440 F.3d
1065, 1069 (9th Cir. 2006) (en banc).

   [1] To withstand review, we must determine that the war-
rant application made a sufficient showing that there was
probable cause for the magistrate to believe that the pictures
likely to be found on Battershell’s computer depicted: (1) sex-
ually explicit conduct; and (2) a minor engaged in that con-
duct. See 18 U.S.C. §§ 2252(A) and 2256. We are satisfied
that it did.1
   1
     Our analysis is no different where First Amendment concerns may be
at issue, such as the case here when photographs are expected to be seized
pursuant to the warrant. See New York v. P.J. Video, Inc., 475 U.S. 868,
875 (1986) (“[A]n application for a warrant authorizing the seizure of
materials presumptively protected by the First Amendment should be eval-
uated under the same standard of probable cause used to review warrant
applications generally.”).
                   UNITED STATES v. BATTERSHELL                     9267
                                    B

   [2] Federal law2 defines five categories of “sexually explicit
conduct” with respect to child pornography. See 18 U.S.C.
§ 2256(2)(A). The first four categories deal with specific con-
duct that is easy to identify and describe: “(i) sexual inter-
course, including genital-genital, oral-genital, anal-genital, or
oral-anal, whether between persons of the same or opposite
sex; (ii) bestiality; (iii) masturbation; [and] (iv) sadistic or
masochistic abuse . . . .” Id.; see also United States v. Jasorka,
153 F.3d 58, 60 (2d Cir. 1998) (quoting the district court’s
declaration that the conduct involved in the first four catego-
ries is “clearly defined and easily recognized”). The second
photo falls within the first category.

   [3] The fifth category, exemplified by the bathtub photo, is
the “lascivious exhibition of the genitals or pubic area of any
person.” 18 U.S.C. § 2256(2)(A)(v). The fifth category, which
turns on the meaning of “lascivious,” is far more subjective
and open to interpretation than the first four. See United
States v. Brunette, 256 F.3d 14, 18 (1st Cir. 2001) (“[T]he
identification of images that are lascivious will almost always
involve, to some degree, a subjective and conclusory determi-
nation on the part of the viewer.” (internal quotation marks
omitted)); United States v. Getzel, 196 F. Supp. 2d 88, 91
(D.N.H. 2002) (ruling that the identification of images as las-
civious is “subjective”).

  [4] Officer Lobdell described the first photograph as “a
young female (8-10 YOA) naked in a bathtub.” The govern-
ment correctly concedes that the description of the first photo-
  2
    Although the warrant application sought evidence of violations of a
Washington statute—Wash. Rev. Code § 9.68A.070, Possession of Depic-
tions of Minors Engaged in Sexually Explicit Conduct—the United States
Attorney correctly notes that “[f]or purposes of the probable cause analy-
sis, there is no meaningful difference between the Washington statute and
the federal child pornography statutes.”
9268            UNITED STATES v. BATTERSHELL
graph is insufficient to establish probable cause because the
first photograph falls within the fifth category of child por-
nography: “lascivious exhibition of the genitals or pubic
area.” Officer Lobdell’s terse description, absent an accompa-
nying photograph, is insufficient to establish probable cause
that the photograph lasciviously exhibited the genitals or
pubic area because his conclusory statement is an inherently
subjective analysis and it is unclear if the photograph exhib-
ited the young female’s genitals or pubic area. See Brunette,
256 F.3d at 18-19.

  [5] Officer Lobdell described the second image as depicting
“another young female having sexual intercourse with an
adult male.” Both federal law and Washington law define
“sexual intercourse” as “sexually explicit conduct.” Compare
18 U.S.C. § 2256(2)(A) with Wash. Rev. Code § 9.68A.070.
We explained in United States v. Smith, 795 F.2d 841 (9th
Cir. 1986), that:

    The statement that the photographs depict sexually
    explicit conduct is similar to many other factual con-
    clusions routinely accepted by courts in applications
    for warrants . . . . [F]actual conclusions are a normal,
    necessary, and perfectly acceptable part of an affida-
    vit . . . .

Id. at 848 n.7. Under Gates, courts are directed to evaluate
probable cause based on “all the circumstances set forth” in
the warrant application. 462 U.S. at 238; see also Smith, 795
F.2d at 849 (stating that the warrant application “does not
stand on the evaluation of the photographs alone”). The Gates
approach “permits a balanced assessment of the relative
weights of all the various indicia of reliability” surrounding
informants’ tips. Gates, 462 U.S. at 234.

   [6] Significant to our ruling is the fact that the warrant
application also included statements from Smith and her sister
that the “Potter” folder on Battershell’s computer had “pic-
                 UNITED STATES v. BATTERSHELL               9269
tures that they believed were kids having sex.” This statement
is one circumstance that creates a fair probability that visual
depictions of minors engaged in sexually explicit conduct will
be found on Battershell’s computer. Indeed, the circumstances
presented in the warrant application show that the information
provided by Smith and her sister was highly reliable. Smith
was turning in her boyfriend, which enhances the credibility
of her statement. Also, Smith and her sister did not give their
information anonymously. Rather, their identities were
“known to law enforcement and thus [they were] liable to
repercussions” if they lied about what they had seen. United
States v. Harding, 273 F. Supp. 2d 411, 419 (S.D.N.Y. 2003).
Officer Lobdell corroborated the report by viewing samples of
what the two women had discovered.

   Battershell argues that the warrant application is invalid
without the accompanying photographs or other support suffi-
cient to permit the issuing magistrate to make an independent
probable cause determination. Battershell grounds his claim
on our decision in Smith. In Smith, we upheld a warrant to
search the defendant’s apartment that had issued based on a
postal inspector’s affidavit asserting that photos depicted “ex-
plicit sexual conduct.” Smith, 795 F.2d at 848. Although we
were “troubled by the fact that the government did not present
and the magistrate did not see the photos in question before
the warrant issued,” id. at 847, we nonetheless upheld the
warrant, in part because the language of the affidavit echoed
the “quite specific” definitions of the child pornography stat-
ute and we determined that the magistrate could “reasonably
consider[ ] the statement of an experienced postal inspector
that the photos depicted ‘sexually explicit conduct’ . . . .” Id.
at 848. We recognize, of course, that in some investigations
of child pornography copies of the pictures sought may not be
readily available even though probable cause to believe they
exist may be established through other means.

   [7] Indeed, a judge may properly issue a warrant based on
factual descriptions of an image. See P.J. Video, 475 U.S. at
9270             UNITED STATES v. BATTERSHELL
874 n.5 (“[W]e have never held that a magistrate must person-
ally view allegedly obscene films prior to issuing a warrant
authorizing their seizure. On the contrary, we think that a rea-
sonably specific affidavit describing the content of a film gen-
erally provides an adequate basis for the magistrate to
determine whether there is probable cause . . . .” (internal cita-
tion omitted)); see also United States v. Chrobak, 289 F.3d
1043, 1045 (8th Cir. 2002) (ruling that a magistrate may base
probable cause on viewing images or on a description of
them).

   [8] Battershell relies on the First Circuit’s decision in
United States v. Brunette, however, to argue that the warrant
application was insufficient to establish probable cause. In
Brunette, the First Circuit determined that a warrant applica-
tion, supported by the affiant’s statement that the photograph
at issue depicted “a prepubescent boy lasciviously displaying
his genitals,” was insufficient to establish probable cause. 256
F.3d at 17. The court held that “[o]rdinarily, a magistrate
judge must view an image in order to determine whether it
depicts the lascivious exhibition of a child’s genitals.” Id. at
19.

   [9] With respect to the second photograph, this case is eas-
ily distinguishable from Brunette because it involves an image
in one of the first four categories, (i.e., sexual intercourse)
while Brunette involved an image in the fifth category (i.e.,
lasciviously displaying the genitals). The first four categories,
with the possible exception of the fourth category, which is
not at issue here, involve easily identifiable nouns that are not
qualified by amorphous adjectives. As we stated in Smith,
“[t]he affiant need only be able to identify the specific, clearly
defined acts listed” in the statute, such as sexual intercourse
or bestiality, and such conclusory statements are permissible
to establish probable cause. 795 F.2d at 848 n.7. Elaborate
and detailed descriptions are unnecessary because “[a]ny
rational adult person can recognize sexually explicit conduct
engaged in by children under the age of 16 when he sees it.”
                 UNITED STATES v. BATTERSHELL               9271
United States v. Hurt, 808 F.2d 707, 708 (9th Cir. 1987),
amending 795 F.2d 765 (1986). Thus, the more demanding
standard for establishing probable cause of “lascivious”
images that the First Circuit employed in Brunette does not
apply.

   [10] It would have been preferable if the affiant in this case
had included copies of the photographs in the warrant applica-
tion. See Smith, 795 F.2d at 847. But failing to include a pho-
tograph in a warrant application is not fatal to establishing
probable cause. Id. at 847-48. Indeed, a judge may properly
issue a warrant based on factual descriptions of an image. See
P.J. Video, 475 U.S. at 874 n.5. Officer Lobdell’s description
of the second photograph is sufficient to establish probable
cause.

   [11] Under the totality of the circumstances the warrant
application, including Smith and her sister’s statements and
Officer Lobdell’s report confirming their observations, estab-
lished a fair probability that Battershell’s computer contained
images of sexually explicit conduct.

                               C

  [12] The only remaining question is whether the warrant
application was sufficient to permit the judge to conclude it
was fairly probable that the person engaged in the sexually
explicit conduct depicted in the second photograph was a
minor.

   [13] Officer Lobdell described the first image as showing
a naked “young female (8-10 YOA).” In the very next sen-
tence, Officer Lobdell described the second picture as show-
ing “another young female having sexual intercourse.” The
word, “another,” is an adjective whose meaning is defined by
its reference to an immediately preceding noun. Here, it refers
to a “young female (8-10 YOA).” Having just used the term
“young female” to mean a girl between the ages of eight and
9272            UNITED STATES v. BATTERSHELL
ten, Officer Lobdell’s use of the phrase “another young
female” can only mean, grammatically, that he was describing
another minor between the ages of eight and ten.

   [14] Furthermore, Officer Lobdell noted in his report that
the second young female was having sex with an “adult”
male. His use of the term “adult” for the male, juxtaposed
with the term “young” for the female, suggests that the female
was not an “adult.” Officer Lobdell concluded that the details
in the two enlarged images “confirmed that the pictures were
illegal to obtain.” If Officer Lobdell did not think that the
“young female” in the second picture was a minor, then he
would not have said that the photograph was illegal to obtain.

   Battershell argues that the warrant application was insuffi-
cient to establish probable cause absent an attached copy of
the photographs or “some sort of meaningful confirmation” of
the ages, such as the pediatrician’s analysis in Smith. While
a medical confirmation of the subject’s age may be sufficient
to establish probable cause absent an attached photograph, it
is not necessary. Indeed, we have accepted, for purposes of an
affidavit in support of a search warrant, the conclusory age
estimates made by civilians and other untrained lay witnesses
without demanding a detailed explanation of how the wit-
nesses reached that conclusion. See United States Wiegand,
812 F.2d 1239, 1243 (9th Cir. 1987) (“Common sense sug-
gests that most of the time one can tell the difference between
a child and an adult.”); see also United States v. Hall, 142
F.3d 988, 995 (7th Cir. 1998) (accepting a computer repair-
man’s statement that images showed “minors”); United States
v. Peterson, 294 F. Supp. 2d 797, 806 (D.S.C. 2003) (accept-
ing a computer repairman’s statement that images showed
“pre-pubescent” boys).

   [15] The issuing magistrate properly applied a practical,
common-sense approach in light of the circumstances set
forth in the affidavit, including Officer Lobdell’s description
of the two photographs and the statement of Smith and her
                 UNITED STATES v. BATTERSHELL               9273
sister as to what they had seen before calling the police. This
was sufficient to establish a fair probability that the person in
the image was a child engaged in sexually explicit conduct
with an adult. See Gates, 462 U.S. at 238.

                              III

  [16] The warrant application to search Battershell’s com-
puter established probable cause. The district court’s decision
denying Battershell’s motion to suppress the evidence was
correct and his conditional guilty plea and conviction are
AFFIRMED.
