United States v. Long, Kenneth

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United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT

Argued March 13, 2003 Decided May 16, 2003

No. 02-3003

UNITED STATES OF AMERICA,
APPELLEE

v.

KENNETH KEITH LONG,
APPELLANT

Appeal from the United States District Court
for the District of Columbia
(No. 99cr00182–01)

Neil H. Jaffee, Assistant Federal Public Defender, argued
the cause for appellant. With him on the briefs was A. J.
Kramer, Federal Public Defender.
Mary B. McCord, Assistant U.S. Attorney, argued the
cause for appellee. With her on the brief were Roscoe C.
Howard, Jr., U.S. Attorney, John R. Fisher, Roy W. McLeese

Bills of costs must be filed within 14 days after entry of judgment.
The court looks with disfavor upon motions to file bills of costs out
of time.
 2

III, Gregg A. Maisel and Sherri L. Berthrong, Assistant U.S.
Attorneys.
Before: RANDOLPH and ROGERS, Circuit Judges, and
WILLIAMS, Senior Circuit Judge.
Opinion for the Court filed by Circuit Judge ROGERS.
ROGERS, Circuit Judge: Two main issues predominate in
this appeal of a criminal conviction for interstate transporta-
tion of a minor with intent to engage in criminal sexual
activity and possession of photographs of minors engaged in
sexually explicit conduct. The first issue is whether the
district court abused its discretion in admitting other-acts
evidence and expert testimony; the second involves the stan-
dard of proof to be applied at sentencing. Kenneth Keith
Long appeals his conviction on the ground that the district
court admitted extrinsic evidence of Long’s sexual activity
with young adults and of his possession of photographs
depicting unidentified individuals for no proper reason under
Federal Rule of Evidence 404(b), thereby creating a prejudi-
cial risk of misuse of the evidence to show propensity under
Federal Rule of Evidence 403. Long also contends that the
district court erred by permitting the government to intro-
duce expert testimony profiling ‘‘preferential sex offenders’’
in violation of Federal Rules of Evidence 404(a) and 403.
Long’s challenge to his sentence arises because the district
court’s application of the cross references in §§ 2G1.1(c)(1)
and 2G2.4(c)(1) of the Sentencing Guidelines resulted in an
eight-level increase in his offense level. He contends that
this increase required clear and convincing proof (of which, he
claims, there is none) to show that his offenses included
conduct that had as its purpose the production of sexually
explicit depictions of the minors, as required by the cross
references.
Under Rules 401, 403, and 404, a defendant is entitled to
the considered judgment of the district court before evidence
of uncharged conduct is admitted. In the main, these are
rules of admission, subject to limited exceptions to be applied
in the exercise of the district court’s discretion. The record
makes clear that Long received his due. The district court’s
examination of the government’s proffered evidence was sen-
 3

sitive to the prejudicial effect of which Long complains on
appeal, while remaining responsive to the government’s need
to rebut Long’s defense and present its case, see Old Chief v.
United States, 519 U.S. 172, 182–83, 187–88 (1997), and we
find no abuse of discretion by the district court in the
application of Rules 401, 403, and 404. We further find no
error by the district court in applying a preponderance of the
evidence standard at sentencing, and that Long’s evidentiary
challenges to his sentence fail. Accordingly, because Long’s
challenges to the sufficiency of the evidence under counts four
and seven are without merit, we affirm.

I.
The evidence at trial revealed that Long, a Baptist minister
and substitute teacher, became acquainted through those
positions with a number of minor boys between thirteen and
sixteen years of age. Six of the boys were the victims
underlying the charges in the indictment. According to the
six boys’ trial testimony, Long engaged in a pattern of
conduct that resulted in sexual contact with them, often
taking sexually explicit photographs. In addition to the six
boys, the government called two non-minor males, ‘‘FM’’ and
‘‘AG,’’ ages sixteen and nineteen at the time of their interac-
tion with Long, who testified that Long had engaged in
similar patterns of conduct resulting in sexual activity with
them and had taken sexually explicit photographs. The
government also introduced a large number of photographs—
over 250—found in Long’s apartment, showing the minor
victims and other young males in sexually explicit poses.
Finally, the government presented Federal Bureau of Investi-
gation Agent Kenneth Lanning, who testified as an expert ‘‘in
the field of sexual exploitation of children,’’ including ‘‘the
typology, identification, characteristics, and strategies of sex-
ual offenders, in particular preferential sexual offenders,’’ as
well as ‘‘the characteristics and behavior of child victims of
sexual abuse.’’
Long was tried on a seven-count indictment charging four
counts of interstate transportation of a minor with the intent
 4

to engage in criminal sexual activity, 18 U.S.C. § 2423(a)
(2000), and two counts of possession of visual depictions of
minors engaged in sexually explicit conduct, 18 U.S.C.
§ 2252(a)(4)(B) (2000). The government dismissed a seventh
count, for sexual exploitation of a child, during trial. The
jury returned a split verdict: it found Long guilty of two
counts of interstate transportation and two counts of posses-
sion of child pornography but not guilty of one count of
interstate transportation (of ‘‘JLG’’); it deadlocked on anoth-
er count of interstate transportation (of ‘‘EB’’), which the
government later dismissed. After denying Long’s motion
for a new trial, the district court sentenced Long to 360
months imprisonment followed by three years supervised
release, imposed a fine and assessment, and recommended
mental health counseling under the Bureau of Prisons’ sex
offender treatment program.

II.
On appeal, Long contends that the district court abused its
discretion in admitting two types of evidence. First, Long
contends that the district court erred in admitting the testi-
mony of FM and AG, who were not minors under the
applicable statute at the time of their acquaintances with
Long. Acknowledging that FM’s testimony was ‘‘prejudicial,’’
the district court ruled the testimony was admissible to show
intent, modus operandi, and absence of mistake or accident.
Similarly, the court ruled that AG’s testimony was admissible
and instructed the jury that it could consider AG’s testimony
only to determine whether Long acted with a criminal intent
with respect to the charges in the indictment, engaged in a
scheme or plan, used a similar modus operandi, had a motive
to commit the charged crimes, or acted knowingly. The court
cautioned that the jury could not consider either man’s testi-
mony to find that Long had a bad character or criminal
propensity. Long contends that testimony about his lawful
acts was not relevant under Federal Rule of Evidence 401 to
establishing criminal intent, modus operandi, or a common
plan or scheme. He further contends that the testimony was
inadmissible character evidence under Rule 404(b) and should
 5

have been excluded under Rule 403 because its unfair preju-
dicial effect substantially outweighed its probative value.
Our review of the district court’s Rule 404(b) rulings is for
abuse of discretion, United States v. Bowie, 232 F.3d 923,
926–27 (D.C. Cir. 2000) (citations omitted), and necessarily
affords the district court ‘‘much deference,’’ United States v.
Cassell, 292 F.3d 788, 792 (D.C. Cir. 2002) (quotation and
citation omitted). A district court’s ruling on a Rule 404(b)
objection will be sustained so long as the evidence is relevant
under Rule 401 and is offered as proof of a matter other than
the defendant’s character or propensity to commit a crime.
Bowie, 232 F.3d at 930. Evidence of similar acts must also be
sufficient to support a jury finding that the defendant com-
mitted the other crime or act. Huddleston v. United States,
485 U.S. 681, 689 (1988).
Under Rule 401, evidence is relevant if it has ‘‘any tenden-
cy to make the existence of any fact that is of consequence to
the determination of the action more probable or less proba-
ble than it would be without the evidence.’’ Fed. R. Evid.
401. Not all relevant evidence, however, is admissible. Rule
404(b) provides that ‘‘[e]vidence of other crimes, wrongs, or
acts is not admissible to prove the character of a person in
order to show action in conformity therewith.’’ Fed. R. Evid.
404(b). But the rule stipulates that such evidence ‘‘may TTT
be admissible for other purposes, such as proof of motive,
opportunity, intent, preparation, plan, knowledge, identity, or
absence of mistake or accidentTTTT’’ Id. Under the law of
this circuit, ‘‘Rule 404(b) is a rule of inclusion rather than
exclusion,’’ Bowie, 232 F.3d at 929, and it is ‘‘quite permis-
sive,’’ excluding evidence only if it is offered for the sole
purpose of proving that a person’s actions conformed to his or
her character. Id. at 929–30 (quotation and citations omit-
ted).
Among the several grounds for admitting the testimony of
FM and AG, the district court found that it was probative of
Long’s intent to engage in criminal sexual conduct with the
six minor victims. Long contends that this was not a proper
ground for admission because there is an incongruence be-
 6

tween Long’s intent to engage in lawful sexual conduct with
males over the age of sixteen and his alleged intent to engage
in unlawful sexual conduct with minor boys. Extrinsic act
evidence is admissible under the intent theory, he maintains,
only if the intent underlying the extrinsic act is the same
illegal intent required for the charged act.
Evidence of a similar act must meet a threshold level of
similarity in order to be admissible to prove intent, see
Jankins v. TDC Mgmt. Corp., 21 F.3d 436, 441 (D.C. Cir.
1994); United States v. Foskey, 636 F.2d 517, 524 (D.C. Cir.
1980), but the court has not required the sort of exact
congruence that Long suggests. On the contrary, ‘‘Rule
404(b)’s terminology ‘other crimes, wrongs, or acts’ includes
conduct that is neither criminal nor unlawful if it is relevant
to a consequential fact.’’ 2 Weinstein’s Federal Evidence
§ 404.20[2][a] (2d ed. 2003) (footnote omitted). The other
activity need not have resulted in a charge or conviction;
indeed, the defendant may even have been acquitted of the
conduct, or the conduct may have been entirely lawful. Id.
§ 404.21[2][b]; e.g., United States v. Cavin, 39 F.3d 1299,
1311 (5th Cir. 1994); United States v. Ashman, 979 F.2d 469,
492 (7th Cir. 1992); United States v. Brown, 961 F.2d 1039,
1042 (2d Cir. 1992); United States v. Atwell, 766 F.2d 416,
421–22 (10th Cir. 1985) (per curiam). What matters is that
the evidence be relevant ‘‘to show a pattern of operation that
would suggest intent’’ and that tends to undermine the defen-
dant’s innocent explanation. 2 Weinstein’s Federal Evidence
§ 404.22[1][a]. Thus, this court has opined, ‘‘the admissible
bad acts evidence need not show incidents identical to the
events charged, so long as they are closely related to the
offense,’’ United States v. DeLoach, 654 F.2d 763, 769 (D.C.
Cir. 1980), and are probative of intent rather than mere
propensity.
The chief theory of Long’s defense was that the six alleged
minor victims had fabricated their tale of sexual abuse. Long
thus denied not that he had a close relationship with the boys,
but rather that he had ever engaged in sexual activity with
them. The testimony of FM and AG was relevant to show
Long engaged in a ‘‘pattern of operation,’’ 2 Weinstein’s
 7

Federal Evidence § 404.22[1][a], that lends credence to the
minors’ assertions that in their cases as well the seemingly
innocent behavior culminated in sexual contact. The manner
in which Long developed a relationship with the minor boys
was strikingly similar to the way in which he ingratiated
himself to FM and AG. Like the minor victims, FM was a
special education student, and Long asked FM to give Long
‘‘candy’’ whenever Long wanted oral sex, in exchange for
which Long promised to buy FM sneakers and other gifts.
Long also sought to videotape and take photographs of FM
masturbating. AG, too, was a special education student for
whom Long was a substitute teacher, and AG, too, received
offers of gifts from Long in addition to overt sexual advances.
As he had done with the six minors, Long recruited FM and
AG to join the Alpha Phi Gents fraternity, which both wit-
nesses understood would (and, in FM’s case, did) involve
sexual acts. In a similar context, the Seventh Circuit held
that ‘‘classic modus operandi evidence used to respond to the
defense argument that [the defendant] had only innocent
intentions’’ with respect to the young male victim was ‘‘highly
probative of intent.’’ United States v. Romero, 189 F.3d 576,
588 (7th Cir. 1999). So, too, the testimony of FM and AG met
the threshold level of similarity to the charged events and
tended to establish that Long’s pattern of ingratiation was
animated by an intent to engage in sexual contact. As such,
the testimony of FM and AG was admissible for a proper
purpose under Rule 404(b). See United States v. Crowder,
141 F.3d 1202, 1209 (D.C. Cir. 1998) (Crowder II).
Long contends, however, that even if the testimony of FM
and AG was relevant for a purpose unrelated to criminal
propensity, its ‘‘slight probative value was substantially out-
weighed by the unfair risk that the jury would infer that
Long had a propensity to engage in sexual activities with
teenagers—be they minors or young adults.’’ Appellant’s Br.
at 20. Under Rule 403, relevant evidence ‘‘may be excluded if
its probative value is substantially outweighed by the danger
of unfair prejudice, confusion of the issues, or misleading the
jury, or by TTT needless presentation of cumulative evidence.’’
Fed. R. Evid. 403. This court has observed that ‘‘Rule 403
 8

contemplates the thoughtful consideration of the trial court
and leaves the admission of evidence to the sound discretion
of the trial judge.’’ United States v. Boney, 977 F.2d 624, 631
(D.C. Cir. 1992). Because ‘‘[t]he trial court is in the best
position to perform’’ the ‘‘subjective balancing’’ that Rule 403
requires, its decision is reviewed only for ‘‘ ‘grave abuse.’ ’’
United States v. Washington, 969 F.2d 1073, 1081 (D.C. Cir.
1992) (citations omitted).
The district court concluded that the significant probative
value of FM’s and AG’s testimony was ‘‘not substantially
outweighed by the danger of unfair prejudice or confusion of
the issues or misleading the jury’’ in light of instructions that
the court would give to the jury. See Crowder II, 141 F.3d at
1210 (citing Fed. R. Evid. 403, advisory committee notes); see
also United States v. Hersh, 297 F.3d 1233, 1254 n.31 (11th
Cir.), cert. denied, 123 S. Ct. 1319 (2002). Its probative force
arose because the men, at or above the age of consent, were
still teenagers, and Long did not claim they lied about his
sexual contact with them. Limiting instructions may some-
times demand of jurors ‘‘a mental gymnastic which is beyond,
not only their powers, but anybody’s else,’’ Nash v. United
States, 54 F.2d 1006, 1007 (2d Cir. 1932) (L. Hand, J.), and
the nature of the pattern evidence here might suggest that
instructions would have marginal effect, see United States v.
Brown, 490 F.2d 758, 765–66 & nn.20–21, 777–78 (D.C. Cir.
1973); cf. Carter v. District of Columbia, 795 F.2d 116, 126–
27 (D.C. Cir. 1986). But limiting instructions ordinarily
suffice to protect the defendant’s interests. Spencer v. Texas,
385 U.S. 554, 561 (1967). Even though admission for a
proper purpose under Rule 404(b) does not the end the
inquiry, because Rule 403 has an independent role to play,
Rule 403 ‘‘focuses on the ‘danger of unfair prejudice’ and
affords the court discretion to exclude evidence only if that
danger ‘substantially outweigh[s]’ the evidence’s probative
value.’’ United States v. Gartmon, 146 F.3d 1015, 1021 (D.C.
Cir. 1998) (citing Fed. R. Evid. 403). Given the probative
strength of the witnesses’ testimony regarding strikingly
similar conduct and the government’s need to respond to
Long’s defense, Long fails to show that the district court
 9

gravely abused its discretion in admitting the testimony of
FM and AG.
Similar concerns underlie Long’s second evidentiary objec-
tion to the admission of ‘‘voluminous’’ photographic evidence.
Long challenges the admission of photographs and negatives
that were not part of the child pornography charges in counts
six and seven but instead were seized from Long’s home after
his arrest. He contends that evidence of his possession of
these uncharged photographs was irrelevant because the
photographs were not proven to be depictions of minors, and
his possession was therefore lawful. Hence, he maintains, the
substantial number of uncharged, sexually explicit and sug-
gestive photographs only provided bad character evidence
and served no proper purpose under Rule 404(b) inasmuch as
‘‘evidence of lawful possession of certain items is not admissi-
ble under Rule 404(b) to prove unlawful possession of similar
items.’’ Appellant’s Br. at 25.
The district court did not allow the government to offer
into evidence all 301 of its proffered photographs and nega-
tives. Rather, over the course of three days, the court
examined each piece of evidence and spent hours with counsel
in chambers reviewing the photographs in addition to hearing
arguments in court regarding their admissibility. The dis-
trict court then limited the government to introducing photo-
graphs that: (1) corroborate the government witnesses’ testi-
mony of certain events and activity; (2) demonstrate the
minor boys’ relationship with Long; (3) rebut Long’s defense
that the minor victims had fabricated the allegations of sexual
abuse and that he did not possess the charged photographs;
or (4) show modus operandi. The court also instructed the
jury that it could not consider the photographic evidence to
conclude that Long had a ‘‘bad character.’’ With these
limitations, the district court concluded that admission of
uncharged photographs in Long’s possession would not show
mere propensity to collect child pornography but were admis-
sible for legitimate Rule 404(b) purposes. The uncharged
photographic evidence was relevant in light of Long’s denial
of the possession of the child pornography charged in counts
six and seven of the indictment: many of the charged photo-
 10

graphs and negatives were found in packets and envelopes
with the uncharged photographs that the court allowed the
government to introduce into evidence, and Long’s finger-
prints also were found on some of the uncharged photo-
graphs.
It hardly can be denied that ‘‘in cases where a defendant is
charged with unlawful possession of something, evidence that
he possessed the same or similar things at other times is
often quite relevant to his knowledge and intent with regard
to the crime charged.’’ United States v. King, 254 F.3d 1098,
1100 (D.C. Cir. 2001) (citing Huddleston, 485 U.S. at 689).
Hence, ‘‘it [is] within the discretion of the district court to
admit evidence regarding similar acts of possession that
suggest ‘repetitive involvement in the same kind of criminal
activity’ even if they do not involve the same objects.’’ Id. at
1100–01 (quoting United States v. Lego, 855 F.2d 542, 546
(8th Cir. 1988)). Because the evidence of Long’s possession
of the uncharged photographic evidence was probative of
disputed elements—possession and intent—of the charged
offenses, the district court did not abuse its discretion in
allowing admission of certain of the non-charged photographs
in Long’s home. See United States v. Garot, 801 F.2d 1241,
1247 (10th Cir. 1986).
Long’s reliance on Guam v. Shymanovitz, 157 F.3d 1154
(9th Cir. 1998), is misplaced. In Shymanovitz, the defendant
was charged with unlawful sexual activity involving minors,
and the district court admitted, as relevant to intent, police
testimony regarding the contents of sexually explicit maga-
zines found in the defendant’s house, as well as two sexually
explicit articles from the magazines. 157 F.3d at 1155. The
Ninth Circuit held that ‘‘mere possession of reading material
that describes a particular type of activity makes it neither
more nor less likely that a defendant would intentionally
engage in the conduct describedTTTT’’ Id. at 1158. ‘‘At the
very most,’’ the court stated, the magazines tended to show
that the defendant ‘‘had an interest in looking at gay male
pornography, reading gay male erotica, or perhaps even,
reading erotic stories about men engaging in sex with under-
age boys, and not that he actually engaged in, or even had a
 11

propensity to engage in, any sexual conduct of any kind.’’ Id.
at 1158–59. Shymanovitz is distinguishable. The Ninth
Circuit stated that lawful possession of gay erotica was not
probative of the defendant’s intent to engage in the charged
conduct of sexual abuse. Shymanovitz, 157 F.3d at 1158–59.
Even if this is correct, and we express no view on the subject,
the court did not suggest that possession of pornography
would be inadmissible for other, permissible purposes. Here,
as explained, the district court admitted the uncharged photo-
graphic evidence for purposes that were both specific and
unrelated to propensity. Hence, Long fails to show an abuse
of discretion under Rule 404(b).
Of course, evidence that is admissible under Rule 404(b)
may still be excluded under Rule 403 ‘‘if its probative value is
substantially outweighed by the danger of unfair preju-
diceTTTT’’ Fed. R. Evid. 403. Long contends that ‘‘[t]he
sheer volume of the extrinsic photographic evidence contrib-
uted to its prejudicial impact’’ and that ‘‘the devastating effect
of the hundreds of photos of mostly unidentified young males
substantially outweighed their marginal probative value un-
der Rule 403.’’ Appellant’s Br. at 28. In Long’s view, the
district court ‘‘should have severely restricted the number of
photographs of young males viewed by the jury and excluded
virtually all of the uncharged sexually explicit or suggestive
ones.’’ Appellant’s Br. at 29. At oral argument in this court,
the government acknowledged that ‘‘a lot’’ of photographs
were introduced into evidence but contended that the evi-
dence was necessary to rebut Long’s defense of lack of
possession of the charged items.
Under Rule 403, the district court has discretion to exclude
evidence that is unfairly prejudicial where its effect is merely
cumulative. Fed. R. Evid. 403; see, e.g., United States v.
Rose, 104 F.3d 1408, 1414 (1st Cir. 1997); United States v.
Hays, 872 F.2d 582, 588 (5th Cir. 1989); Levin v. United
States, 338 F.2d 265, 273 (D.C. Cir. 1964). There may well be
a point at which the admission of a multitude of photographs
depicting uncharged conduct would tilt so far as to unfairly
prejudice a defendant’s right to a fair trial. But it is difficult,
if not impossible, to draw a line at which such evidence, by
 12

virtue of its sheer volume, necessarily becomes unfairly preju-
dicial. As this court has observed, ‘‘the Rule 403 inquiry in
each case involving Rule 404(b) evidence will be case-specific.
There can be no ‘mechanical solution,’ no per se ruleTTTT’’
Crowder II, 141 F.3d at 1210. Rather than drawing a bright
line, appellate courts have instead enforced the gatekeeping
role of the district court in admitting relevant evidence and
reviewed its decision for abuse of discretion. See United
States v. Manner, 887 F.2d 317, 322–23 (D.C. Cir. 1989).
That is, ‘‘Rule 403 contemplates the thoughtful consideration
of the trial court and leaves the admission of evidence to the
sound discretion of the trial judge.’’ Boney, 977 F.2d at 631.
In Long’s case, the record confirms that the district court
commendably fulfilled its proper role.
The district court reviewed in camera every photograph
that the government sought to introduce into evidence and
heard argument on the admissibility of each. Outside the
presence of the jury, the court identified virtually every
photograph and explained its reasons for admitting or exclud-
ing the evidence. For instance, the court described a number
of photographs that featured nude or partially nude males of
unidentified ages, often sexually aroused or masturbating.
The court ruled that the government would not be allowed to
introduce these photographs into evidence if they contained
no other relevant information that connected Long to the
charged offenses. While undertaking this examination, the
court was mindful of the possibility that the large number of
photographs, taken together, might have an unfair prejudicial
effect. It explained that ‘‘there is a continuum of explicit-
ness,’’ and that, ‘‘to the extent that the quantity of pictures
TTT may together create TTT unfair prejudice,’’ the court was
inclined to exclude the most explicit and least probative
photographs. This is the type of ‘‘thoughtful consideration,’’
Boney, 977 F.2d at 631, that Rule 403 requires. The district
court confined the admission of the uncharged photographs
under Rule 404(b) to four relevant purposes, imposed further
constraints on the photographs’ admission under Rule 403,
and gave limiting instructions to the jury. The court demon-
strated an awareness of the need to exclude photographs at
 13

either extreme, either because they were too explicit or
barely probative. Long has offered no reason why admission
of any particular photograph was an abuse of discretion, or
why the total number created unfair prejudice that ‘‘substan-
tially outweighed’’ the probative purposes found by the dis-
trict court. Consequently, this court cannot conclude that
admission was a ‘‘grave abuse’’ of discretion. Washington,
969 F.2d at 1081.

III.
Long also contends that the district court erred in admit-
ting the expert testimony of FBI Agent Kenneth Lanning.
The district court allowed Lanning to testify ‘‘as an expert
concerning sexual exploitation of children, including the typol-
ogy, identification, characteristics and strategies of a sexual
offender, particularly preferential sex offenders, and the char-
acteristics and behavior of child victims of sexual abuse.’’
Long does not challenge Lanning’s testimony as improper
under the Rules of Evidence that generally govern expert
testimony, Fed. R. Evid. 702–05, or the Supreme Court’s
decisions in Daubert v. Merrell Dow Pharmaceuticals, 509
U.S. 579 (1993), and Kumho Tire Co. v. Carmichael, 526 U.S.
137 (1999). Instead, Long maintains that Lanning’s testimo-
ny amounted to improper character evidence under Rule
404(a)(1) and was unfairly prejudicial under Rule 403. Fed.
R. Evid. 403, 404(a)(1).
Lanning’s testimony focused on the behavior of a class of
criminals he termed ‘‘preferential sex offenders,’’ whose sex
offenses are characterized by ‘‘paraphilia,’’ or ‘‘an attraction
to or intense fantasies TTT involving certain elements.’’ He
opined that ‘‘very often part of their preference is the age and
gender of their victim,’’ and that ‘‘their primary motivation is,
in fact, sexual gratification.’’ Lanning identified three pat-
terns of behavior within the general class of preferential sex
offenders. Among these patterns of behavior is the ‘‘seduc-
tion process,’’ through which the sex offender uses attention,
kindness, gifts, and money to lower his or her victims’ inhibi-
tions. During this process, the sex offender often will use
 14

alcohol, drugs, and pornography to arouse the victims and to
lower further their inhibitions. Lanning also opined that
these offenders often have strong interpersonal skills and
occupy positions of authority, such as a school teacher or
minister, and also are often adept at identifying victims who
are weak and vulnerable, such as children whose family life is
dysfunctional. Lanning added that sex offenders often photo-
graph their victims, and he also offered insight into the
reasons why children who are victimized by a sex offender
may remain in the offender’s presence.
Rule 404(a) provides that ‘‘[e]vidence of a person’s charac-
ter or a trait of character is not admissible for the purpose of
proving action in conformity therewith on a particular occa-
sion,’’ except in specified circumstances. Fed. R. Evid.
404(a). According to Long, Lanning’s testimony contravened
this rule because it tended to show that Long acted in
conformity with the characteristics of a preferential sex of-
fender in committing the charged offenses. Although Long
acknowledges that Lanning did not explicitly testify that
Long exhibited the characteristics of a preferential sex of-
fender, he contends that, to the extent the expert testimony
mirrored the government’s case against him, it was analogous
to the improper use of a criminal profile as substantive
evidence.
‘‘Courts have condemned the use of profiles as substantive
evidence of guilt,’’ United States v. McDonald, 933 F.2d 1519,
1521 (10th Cir. 1991), while acknowledging that there is a
‘‘fine line between potentially improper profile evidence and
acceptable specialized testimony,’’ United States v. Becker,
230 F.3d 1224, 1231 (10th Cir. 2000), cert. denied, 532 U.S.
1000 (2001). In general, the ‘‘profile’’ label is not helpful in
distinguishing admissible from inadmissible expert testimony.
Instead, courts focus on the Federal Rules of Evidence and
the purpose for which the evidence is offered: whether it is
designed improperly to illuminate the defendant’s character
or propensity to engage in criminal activity, or whether
instead it seeks to aid the jury in understanding a pattern of
behavior beyond its ken. Becker, 230 F.3d at 1231; Mc-
Donald, 933 F.2d at 1522; see also Boney, 977 F.2d at 628–
 15

31. Thus, experts may testify regarding the modus operandi
of a certain category of criminals where those criminals’
behavior is not ordinarily familiar to the average layperson,
as in the case of the modus operandi of persons involved in
illegal drug trafficking or prostitution. See, e.g., United
States v. Watson, 171 F.3d 695, 703 (D.C. Cir. 1999); United
States v. White, 116 F.3d 903, 921–22 (D.C. Cir. 1997) (per
curiam); United States v. Chin, 981 F.2d 1275, 1279 (D.C.
Cir. 1992); Boney, 977 F.2d at 627–29 (D.C. Cir. 1992);
United States v. Anderson, 851 F.2d 384, 392–94 (D.C. Cir.
1988). Still, there is ‘‘ ‘a line that expert witnesses may not
cross.’ ’’ United States v. Boyd, 55 F.3d 667, 671 (D.C. Cir.
1995) (citations omitted). ‘‘[W]hat is proscribed is question-
ing that produces responses suggesting some special knowl-
edge of the defendant’s mental processes.’’ Watson, 171 F.3d
at 703 (citation omitted); accord Boyd, 55 F.3d at 672. This
line relates to the limits of Rule 704(b) on opinion evidence
regarding the ultimate issue, not to Rule 404(a)’s constraints
on character evidence.
The admission of Lanning’s testimony has been approved
by the two circuits to have considered it. In United States v.
Romero, 189 F.3d 576 (7th Cir. 1999), the Seventh Circuit
upheld the admission of testimony by Lanning that was
similar to the testimony he offered in Long’s case. As he did
here, Lanning testified in Romero regarding the characteris-
tic patterns of ‘‘preferential sex offenders,’’ but he also re-
sponded to hypothetical questions from the prosecution that
mirrored the defendant’s conduct. Id. at 582–84. The Sev-
enth Circuit noted ‘‘the value of expert testimony in explain-
ing a complicated criminal methodology that may look inno-
cent on the surface but is not as innocent as it appears.’’ Id.
at 584 (citations omitted). The court observed that it was
precisely this value that made Lanning’s testimony helpful to
the jury, because it ‘‘described the modus operandi of modern
child molesters,’’ with which the average juror is unfamiliar.
Id. at 585. Rejecting the contention that Lanning’s testimony
constituted improper character evidence under Rule 404(a),
the court explained that ‘‘[p]resenting character evidence is
an attempt to use a person’s personality or psychological
 16

propensity to prove what the person did.’’ Id. at 587. ‘‘Lan-
ning’s testimony,’’ however, ‘‘did exactly the opposite. It was
an attempt to use [the defendant’s] actions to prove his
psychological propensitiesTTTT As such, it was not really
character evidence at all.’’ Id. The court concluded that,
‘‘[t]o the extent that Agent Lanning discussed the preferences
and psychological proclivities of sex offenders, he did so only
to elaborate on his behavior-driven analysis of their modus
operandi.’’ Id. Also, in United States v. Cross, 928 F.2d
1030, 1034 (11th Cir. 1991), Lanning testified in a prosecution
for mail fraud, mailing obscene material, and conspiracy to
persuade a minor to engage in sexually explicit conduct for
the purpose of producing visual or print media. The Elev-
enth Circuit held that Lanning’s testimony regarding the
‘‘characteristic behaviors of pedophiles’’ was admissible to
show whether the defendant had the intent to use the photo-
graphs to produce and distribute child pornography, to ex-
plain his modus operandi, and to establish that the porno-
graphic photographs at issue—seemingly innocent ‘‘nude
studies’’ of children rather than more graphic child pornogra-
phy—appealed to the prurient interest. Id. at 1049–51.
As noted, this court has generally permitted expert testi-
mony regarding the modus operandi of a certain type of
criminal offender. See, e.g., Watson, 171 F.3d at 703. For
example, in United States v. Anderson, 851 F.2d 384, 392
(D.C. Cir. 1988), the government’s expert witness testified
regarding pimping patterns and the pimp-prostitute relation-
ship. As jurors cannot be presumed to have knowledge of
these matters, the court focused on the fact that the expert’s
testimony ‘‘might have shed light on critical issues in the
case’’ and ‘‘helped the jury to determine the credibility of’’ the
prosecution’s other witnesses. Id. at 393. Thus, because the
‘‘testimony had a significant bearing on facts ‘that could be
determinative of [the defendant’s] guilt or innocence,’ ’’ and in
light of the trial court’s wide discretion, the court held the
testimony to be admissible. Id. (citation omitted). By the
same token, Lanning’s testimony was designed to aid the jury
in understanding the modus operandi of preferential sex
offenders. The Seventh Circuit held in Romero that Lan-
 17

ning’s testimony ‘‘was critical in dispelling from the jurors’
minds the widely held stereotype of a child molester as ‘a
dirty old man in a wrinkled raincoat’ who snatches children
off the street as they wait for the school bus.’’ Romero, 189
F.3d at 584. Similarly, the district court here determined
that the average layperson lacks knowledge regarding the
manner in which preferential sex offenders operate. Long
was a minister of the church and a substitute teacher, posi-
tions a juror would ordinarily view as held by law-abiding
citizens of high moral character. A juror would also be
familiar with the well-known fact that young children are
impressionable and do not always tell the truth, whether
because of exposure to an ambiguous and unfamiliar act,
probing questions about matters relating to sex, or a desire to
please the inquisitor. See generally Maryland v. Craig, 497
U.S. 836 (1990). As the government also notes, Lanning’s
testimony helped to rebut Long’s defenses of innocent intent
and fabrication. Under the circumstances, the district court
did not abuse its discretion in concluding that Lanning’s
expert testimony was admissible under Rule 404(a).
Again, Long contends that even if the expert testimony was
relevant and admissible under Rule 404(a), it was so inherent-
ly prejudicial that the district court should have excluded it
under Rule 403. The Eleventh Circuit rejected this objection
to Lanning’s testimony in Cross, observing that the testimo-
ny’s ‘‘considerable probative value’’ was not outweighed by
any possible prejudicial effect. Cross, 928 F.2d at 1051. The
court also noted that ‘‘because there was extensive, particu-
larized evidence of Cross’s sexual attitudes toward children
offered at trial by the government and, indeed, by Cross
himself, it is doubtful that Lanning’s more generalized testi-
mony about the nature of pedophilia could have independently
affected the jury’s verdict.’’ Id. (citing Anderson, 851 F.2d at
394 (D.C. Cir. 1988)). Moreover, in Anderson, 851 F.2d at
393–94, this court held that the expert testimony regarding
pimps’ modus operandi was not barred by Rule 403, even
though ‘‘the risk of unfair prejudice was heightened by the
sordid and disturbing nature of [the] subject matter,’’ id. at
393; ‘‘[g]iven th[e] large quantity of uncontested, particular-
 18

ized evidence against Anderson in the record,’’ the court
found it ‘‘almost inconceivable that [the expert’s] general,
more attenuated, testimony about the prostitution underworld
could have independently affected the jury’s verdict,’’ id. at
394, and its admission ‘‘was, at worst, harmless error,’’ id.
For much the same reasons as in Cross and Anderson,
Long’s Rule 403 objection fails: Lanning’s testimony was
offered for a permissible purpose, namely to identify the
behavior and actions of child molesters and explain their
modus operandi, the prosecution adduced considerable other
evidence of Long’s pedophilia, and the jury was instructed
that the weight to be given to Lanning’s testimony was for
the jurors to determine. See Cross, 928 F.2d at 1051;
Anderson, 851 F.2d at 393–94. Long suggests the Rule 403
balance tilts in his favor because the probative value of the
expert testimony was undermined by Lanning’s failure to
include any statistical analysis from his case studies to indi-
cate the prevalence of the various behavioral patterns and
characteristics among preferential sex offenders. While this
suggestion appears more to be an objection to the expert’s
qualifications on Daubert grounds, an objection that Long has
not made on appeal, it falls short when viewed as a Rule 403
contention, because expert testimony need not be based on
statistical analysis in order to be probative. Cf. Kumho Tire,
526 U.S. at 150. Rather, because ‘‘[t]his testimony illuminat-
ed how seemingly innocent conduct TTT could be part of a
seduction technique,’’ it ‘‘shed light on a critical issue in the
case,’’ Romero, 189 F.3d at 585, and hence, the district court
did not abuse its discretion in concluding that its probative
value was not ‘‘substantially outweighed’’ by its unfair preju-
dicial effect, Fed. R. Evid. 403.

IV.
Long’s challenges to the sufficiency of the evidence of the
interstate transportation of one of the minor boys (‘‘JS’’) and
the possession of photographic negatives require only brief
response.
 19

Viewing the evidence, as we must, in the light most favor-
able to the government, United States v. Morris, 977 F.2d
617, 619 (D.C. Cir. 1992), we hold that there was sufficient
evidence from which a reasonable juror could find that, at the
time Long transported one of the victims, JS, from Puerto
Rico to the District of Columbia, JS was a minor. Although
JS testified that he was sixteen years old when he traveled to
the District of Columbia, the government offered evidence
that JS was born on June 22, 1982; that he twice came to
visit Long in the District of Columbia; and that JS’s first visit
was, as he testified, on an American Airlines flight with a
connection in Miami. An American Airlines employee testi-
fied that Long purchased a ticket in JS’s name for an
American Airlines flight from San Juan, Puerto Rico, to
Washington, D.C., that departed San Juan and connected in
Miami on May 28, 1998, a month before JS turned sixteen;
airline records indicated that someone used this ticket after
presenting identification in JS’s name. A juror reasonably
could have found that JS incorrectly recalled his age and that
the American Airlines records (which are kept in a highly
secure location in Tulsa, Oklahoma) are a more reliable
source than the young witness’s memory.
We also hold that there was sufficient evidence to sustain
Long’s conviction on count seven for possession of photo-
graphic negatives of child pornography. See Morris, 977
F.2d at 619. Long contends that the prosecution failed to
establish that he constructively possessed the photographic
negatives because law enforcement officers found the nega-
tives during a search of his home three weeks after their
initial search, and in a location (a trunk on the porch off the
master bedroom) that they had previously searched. Long
had not been in his home since the original search, and
another man, Andre Lazenby, had been residing there in
Long’s absence. According to the government’s evidence:
(1) it was undisputed that Long owned the house and resided
there; (2) Lazenby denied knowledge of the photographic
negatives; (3) the six victims identified photographs devel-
oped from the negatives as photos of them that Long had
taken; (4) the negatives were linked to photographs contain-
 20

ing Long’s fingerprints; (5) the negatives included depictions
of Long’s possessions; and (6) photographs from other ex-
hibits that the police found during the initial search were de-
veloped from the negatives. Based on this evidence, a rea-
sonable juror could infer that Long exercised constructive
possession over the items found in his home. See Morris,
977 F.2d at 620 (D.C. Cir. 1992) (citing United States v.
Jenkins, 928 F.2d 1175, 1179 (D.C. Cir. 1991)).

V.
Long’s challenge to his sentence focuses on the standard of
proof. He contends that the district court erred in enhancing
Long’s base offense level by eight levels on the basis of
acquitted conduct without finding by clear and convincing
evidence that Long engaged in the relevant conduct. This
court reviews a sentencing court’s factual determinations for
clear error, United States v. Jackson, 161 F.3d 24, 28 (D.C.
Cir. 1998), and affords ‘‘due deference’’ to the district court’s
application of the Sentencing Guidelines to the facts, 18
U.S.C. § 3742(e) (2000); Jackson, 161 F.3d at 28. This court
reviews legal questions de novo, such as the standard of proof
that applies to sentence enhancements under the Sentencing
Guidelines. United States v. Montague, 40 F.3d 1251, 1252–
53 (D.C. Cir. 1994).
Section 2G1.1 of the Sentencing Guidelines applies to con-
victions for interstate transportation of minors with the intent
to engage in criminal sexual activity. United States Sentenc-
ing Commission Guidelines Manual (‘‘U.S.S.G.’’) § 2G1.1
(2000). A cross reference provides, however, that ‘‘[i]f the
offense involved causing, transporting, permitting, or offering
TTT a person less than 18 years of age to engage in sexually
explicit conduct for the purpose of producing a visual de-
piction of such conduct,’’ the sentencing court is to apply
Guideline § 2G2.1. U.S.S.G. § 2G1.1(c)(1). The district
court found that the cross reference applied and treated
§ 2G2.1 as the controlling Guideline provision. United States
v. Long, 185 F. Supp. 2d 30, 35 (D.D.C. 2001). Similarly,
although § 2G2.4 applies to convictions for possession of
 21

visual depictions of minors engaged in sexually explicit con-
duct, a virtually identical cross reference directs the district
court to apply § 2G2.1 if the offense involved causing or
transporting ‘‘a minor TTT for the purpose of producing a
visual depiction’’ of sexually explicit conduct. U.S.S.G.
§ 2G2.4(c)(1). Again, the district court found that the cross
section applied and treated § 2G2.1 as controlling. Long, 185
F. Supp. 2d at 35. The application of the cross references
resulted in an eight-level increase in Long’s base offense
level. Compare U.S.S.G. § 2G1.1(a)(1) (specifying base of-
fense level of nineteen), with U.S.S.G. § 2G2.1(a) (setting
base offense level of twenty-seven); see also Long, 185
F. Supp. 2d at 35.
Long acknowledges that the preponderance of the evidence
standard ordinarily applies to sentencing determinations.
McMillan v. Pennsylvania, 477 U.S. 79, 91–92 (1986). In
fact, the Sentencing Commission has suggested ‘‘that use of a
preponderance of the evidence standard is appropriate to
meet due process requirements and policy concerns in resolv-
ing disputes regarding application of the guidelines to the
facts of a case.’’ U.S.S.G. § 6A1.3 (Policy Statement) com-
mentary (2000). And the Supreme Court has held that a
sentencing court may take acquitted conduct into account in
setting the appropriate sentence. United States v. Watts, 519
U.S. 148, 152–53 (1997) (per curiam). But Long contends
that in extraordinary circumstances, such as the eight-level
increase in his sentence, where the disputed sentencing fac-
tors become ‘‘a tail which wags the dog of the substantive
offense,’’ McMillan, 477 U.S. at 88, due process requires
proof by clear and convincing evidence.
The Supreme Court has noted ‘‘a divergence of opinion
among the Circuits as to whether, in extreme circumstances,
relevant conduct that would dramatically increase the sen-
tence must be based on clear and convincing evidence.’’
Watts, 519 U.S. at 156 (footnote omitted). Two circuits have
required clear and convincing evidence for extreme sentenc-
ing enhancements. See United States v. Jordan, 256 F.3d
922, 927–29 (9th Cir. 2001); United States v. Paster, 173 F.3d
206, 219–21 (3d Cir. 1999); United States v. Kikumura, 918
 22

F.2d 1084, 1097–1102 (3d Cir. 1990). At least two circuits,
however, have rejected a heightened standard of proof at
sentencing, see, e.g., United States v. (Randy) Graham, 275
F.3d 490, 517 n.19 (6th Cir. 2001), cert. denied, 535 U.S. 1026
(2002); United States v. Washington, 11 F.3d 1510, 1516
(10th Cir. 1993), while others have found that the case before
them did not merit a higher standard, see, e.g., United States
v. Montgomery, 262 F.3d 233, 249–50 (4th Cir.), cert. denied,
534 U.S. 1034 (2001); United States v. Cordoba–Murgas, 233
F.3d 704, 709 (2d Cir. 2000); United States v. Lewis, 115 F.3d
1531, 1536–37 (11th Cir. 1997); United States v. Miner, 127
F.3d 610, 613–14 (7th Cir. 1997); United States v. Lombard,
102 F.3d 1, 5 (1st Cir. 1996); United States v. Thompson, 51
F.3d 122, 125 (8th Cir. 1995); United States v. Vital, 68 F.3d
114, 121 (5th Cir. 1995). This court, for its part, has noted
the split among the circuits on this issue but has declined to
require more than the preponderance standard at sentencing.
See United States v. (Steven A.) Graham, 317 F.3d 262, 269–
70 (D.C. Cir. 2003); United States v. Jackson, 161 F.3d 24,
26–27 (D.C. Cir. 1998); United States v. Toms, 136 F.3d 176,
186–87 (D.C. Cir. 1998); United States v. Lam Kwong–Wah,
966 F.2d 682, 687–88 (D.C. Cir. 1992), overruled on other
grounds, United States v. Fields, 242 F.3d 393, 396 (D.C. Cir.
2001).
The Supreme Court has ‘‘held that application of the pre-
ponderance standard at sentencing generally satisfies due
process.’’ Watts, 519 U.S. at 156 (citing McMillan v. Penn-
sylvania, 477 U.S. 79, 91–92 (1986)). As the Court has
explained, ‘‘[s]entencing courts have traditionally heard evi-
dence and found facts without any prescribed burden of proof
at all.’’ McMillan, 477 U.S. at 91 (citing Williams v. New
York, 337 U.S. 241 (1949)). In McMillan, the Court stated
that ‘‘embracing [the] suggestion that we apply the clear-and-
convincing standard TTT would significantly alter criminal
sentencingTTTT’’ Id. at 92 n.8. And the Court has made
clear that McMillan’s reasoning remains undisturbed in the
wake of Apprendi v. New Jersey, 530 U.S. 466 (2000). Har-
ris v. United States, 122 S. Ct. 2406, 2419–20 (2002). To date,
then, the Supreme Court has held that a preponderance
 23

standard provides sufficient safeguards to satisfy the require-
ments of due process at sentencing. Watts, 519 U.S. at 157.
Lower courts, however, have recognized that ‘‘legal rules—
even rules that function perfectly well in familiar contexts
when stated in categorical terms—cannot always be applied
in extreme situations.’’ Kikumura, 918 F.2d at 1100 (3d Cir.
1990). The Third Circuit in Kikumura limited its holding to
the ‘‘extreme context’’ in which the district court’s findings
regarding uncharged conduct increased the defendant’s sen-
tence ‘‘from about 30 months to 30 years—the equivalent of a
22–level increase in his offense level.’’ Id. at 1100–01. The
court distinguished this ‘‘most dramatic example’’ from other,
smaller increases in the base offense level under the Sentenc-
ing Guidelines, suggesting that the preponderance standard
provides sufficient due process protections for ‘‘probably even
a ten-level increaseTTTT’’ Id. at 1100. Here, the district
court’s application of the Guideline’s cross references resulted
in an eight-level increase in Long’s base offense level—an
increase that the Kikumura court speculated would not merit
a heightened burden of proof. Id. Although the Third
Circuit has subsequently held that the clear and convincing
standard was required for a nine-level upward departure for
extreme conduct, United States v. Paster, 173 F.3d 206, 219–
20 (3d Cir. 1999), in that case the departure would have
negated the effect of the defendant’s guilty plea and under-
mined principles of proportionality, id. at 220–21. Long’s
sentence, by contrast, does not present such an extreme case.
The cross references at issue operate to increase Long’s base
offense level on the basis of conduct closely related to the
charged crimes, see Lam, 966 F.2d at 688; see also United
States v. Pugh, 25 F.3d 669, 676 (8th Cir. 1994), and therefore
the sentencing enhancement was not the tail that wagged the
dog of the substantive offense, McMillan, 477 U.S. at 88;
Kikumura, 918 F.2d at 1100–01. We accordingly hold that
the district court did not err by failing to treat Long’s case as
presenting ‘‘extraordinary circumstances,’’ Lam, 966 F.2d at
688; accord Jackson, 161 F.3d at 26–27, that require a
heightened standard of proof.
 24

Because the district court applied the correct standard of
proof at sentencing, there is no merit to Long’s challenge to
the findings that Long’s ‘‘purpose’’ in transporting the minors
more likely than not was to create child pornography, thereby
justifying application of the § 2G1.1(c)(1) cross reference.
There was ample evidence that Long had taken sexually
explicit photographs of each of the six minor victims, and the
testimony of the victims, and Lanning, supports the finding
that Long’s transportation of the minors was motivated at
least in part by a desire to create these visual depictions.
Long, 185 F. Supp. 2d at 38–43. For example, crediting the
testimony of ‘‘JEG’’ regarding the numerous occasions over
the two years that Long had transported the minor to the
District of Columbia and the jury’s conclusion that Long had
intended to engage in sexual conduct, the district court
determined that it was ‘‘implausible’’ that Long had not also
intended on some of those occasions to induce the sexual
conduct in order to photograph it. Id. at 38.
Accordingly, we hold that: there was no abuse of discretion
in the district court’s evidentiary rulings under Rules 401,
403, and 404(a) and (b); there was sufficient evidence for
conviction of the charges in counts six and seven; and there
was no error at sentencing, and we affirm the judgment of
conviction.