                           PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,              
                 Plaintiff-Appellee,
                 v.                              No. 01-5002
STEPHANIE MOHR,
              Defendant-Appellant.
                                       
           Appeal from the United States District Court
            for the District of Maryland, at Greenbelt.
              Deborah K. Chasanow, District Judge.
                            (CR-00-453)

                      Argued: December 6, 2002

                      Decided: February 3, 2003

  Before WILKINSON, Chief Judge, MOTZ, Circuit Judge, and
      James P. JONES, United States District Judge for the
       Western District of Virginia, sitting by designation.



Affirmed by published opinion. Judge Motz wrote the opinion, in
which Chief Judge Wilkinson and Judge Jones joined.


                             COUNSEL

ARGUED: Fred Warren Bennett, BENNETT & NATHANS, L.L.P.,
Greenbelt, Maryland, for Appellant. Steven Michael Dettelbach,
Assistant United States Attorney, Greenbelt, Maryland, for Appellee.
ON BRIEF: Booth M. Ripke, BENNETT & NATHANS, L.L.P.,
Greenbelt, Maryland, for Appellant. Thomas M. DiBiagio, United
2                       UNITED STATES v. MOHR
States Attorney, Sandra Wilkinson, Assistant United States Attorney,
Greenbelt, Maryland; Ralph F. Boyd, Jr., Assistant Attorney General,
Jessica Dunsay Silver, Gregory B. Friel, Appellate Section, Civil
Rights Division, UNITED STATES DEPARTMENT OF JUSTICE,
Washington, D.C., for Appellee.


                              OPINION

DIANA GRIBBON MOTZ, Circuit Judge:

   A jury convicted Stephanie Mohr, a Prince George’s County,
Maryland police officer, of unlawfully releasing her police dog in vio-
lation of 18 U.S.C.A. § 242 (West 2000). On appeal, Mohr challenges
evidentiary rulings in which the district court (1) admitted testimony
of subsequent incidents of intentional misuse of a police dog by
Mohr; (2) permitted a government expert to testify on prevailing prac-
tices for use of a police dog; and (3) admitted a witness’s prior consis-
tent statement and allowed him to explain his reason for making that
statement.1 We affirm.

                                   I.

   On September 21, 1995, Officer Wendell Brantley, of the Takoma
Park, Maryland Police Department, was conducting surveillance in
the Holton Lane area of Prince George’s County because of a number
of commercial burglaries in that area. At approximately 2 a.m., Offi-
cer Brantley spotted two men on the roof of the Sligo Press building.
He called for assistance and several Takoma Park officers, including
    1
    Mohr also claims ineffective assistance of counsel because the lawyer
who represented her before the district court filed one pre-trial motion
late. A claim of ineffective assistance of counsel should be raised
through a motion under 28 U.S.C. § 2255 (West 1994 & Supp. 2002)
rather than on direct appeal, "unless it ‘conclusively appears’ from the
record that defense counsel did not provide effective representation."
United States v. Richardson, 195 F.3d 192, 198 (4th Cir. 1999) (citation
omitted). Here, it does not "conclusively appear" from the record that
Mohr received ineffective assistance of counsel. Accordingly, we do not
consider the claim on this direct appeal.
                         UNITED STATES v. MOHR                           3
Sergeant Dennis Bonn, responded. Bonn then asked for assistance
from Prince George’s County and specifically requested a K-9 dog.
Prince George’s K-9 officers Mohr and Anthony Delozier arrived
with Mohr’s police dog. Bonn also called for a Maryland State Police
helicopter, which illuminated the entire roof with a powerful light cal-
led a "night sun."

    Bonn, with corroboration from three other police eyewitnesses, tes-
tified to the government’s version of how and why Mohr released her
police dog on Ricardo Mendez, one of the suspects on the roof. After
the helicopter arrived, the officers ordered the suspects to come to the
back of the roof. Mendez and the other suspect, Jorge Herrera-Cruz,
did so and held their hands in the air, as directed by the officers.
Then, again as directed by the officers, the suspects climbed down
from the roof, keeping their hands in the air, and eventually facing the
officers, who surrounded them in a semicircle, some with their guns
drawn. Bonn testified that the suspects followed all police commands.

   As the suspects stood with their hands up in the air, Delozier
approached Bonn and asked: "Sarge, can the dog get a bite?" Bonn
"responded with one word, which was yes." Bonn testified that "[a]t
that time, [the suspects] still had their hands in the air and they
weren’t doing anything." Bonn then witnessed Delozier and Mohr
have "a very, very brief exchange," followed by Mohr releasing the
dog. The dog attacked Mendez, who "still had his hands in the air
when . . . the dog bit him in the leg. [He] went down screaming and
continued to scream." Bonn testified that, prior to Mohr’s release of
the dog, Mendez did not make "any sudden movement," did not "fail
to comply with police command[s]," did not "lower his hands," and
did not "attempt to flee in any way." Bonn did not hear any K-9 warn-
ing prior to Mohr’s release of the dog or at any point during the evening.2
As a result of the incident, Bonn pled guilty as an accessory-after-the-
fact to a civil rights violation and testified for the government pursu-
ant to a plea agreement.
  2
   A K-9 warning is a "loud verbal" announcement made prior to release
of the dog, which allows "innocent persons to exit the area and afford[s]
suspects an opportunity to surrender." Vathekan v. Prince George’s
County, 154 F.3d 173, 176 (4th Cir. 1998).
4                       UNITED STATES v. MOHR
   Mohr took the stand and offered a very different version of the
events. She testified that she gave a K-9 warning while Mendez and
Herrera-Cruz were on the roof. Mohr further testified that Mendez did
not follow her orders to stop when he climbed down from the roof,
and that he did not raise his hands: "Mr. Mendez’s hands never went
up. He had them in the front of his body, around his waistband area.
Sometimes I could see his hands and sometimes they went out of my
sight in front of his body. There [were] times that I couldn’t see his
hands, and I was ordering him — I was issuing him command after
command to raise his hands, and he didn’t." Mohr did not believe that
either suspect had been frisked. She then observed Mendez "turn his
body and his feet to the left and make a movement to the left, [and]
as soon as [she] saw him do that, it meant to [her] that he was going
to run to the left" and "attempt to flee" toward an avenue of escape
where she believed there were no officers. Mohr explained that she
did not have time to give her usual K-9 warning but yelled to Mendez
to stop. She then released the dog. Mohr testified that Delozier did not
speak to her prior to releasing the dog and that she alone made the
decision to do so. Mohr acknowledges that Mendez suffered "at least
one serious dog bite."

   It was subsequently discovered that Mendez and Herrera-Cruz
were homeless and were simply sleeping on the roof. The parties stip-
ulated that the Takoma Park Police Department charged both men
with burglary in the fourth degree. Charges against Mendez were sub-
sequently dismissed. Herrera-Cruz was jailed for 60 days, appeared
in court without an attorney and pled guilty; he was sentenced to time
served.

   On September 20, 2000, a federal grand jury returned an indict-
ment charging Mohr and Delozier with violating 18 U.S.C.A. § 242
(West 2000), by acting under color of law to willfully deprive
Mendez of his right to be free from the use of unreasonable force.
Mohr and Delozier were also charged with a conspiracy, in violation
of 18 U.S.C.A. § 371 (West 2000). A jury trial was held from Febru-
ary 26 through March 14, 2001. The jury acquitted Mohr of conspir-
acy and Delozier of the § 242 offense. Because the jury could not
reach a verdict on the § 242 charge against Mohr and the conspiracy
charge against Delozier, the trial court declared a mistrial on those
two counts. A second trial commenced on July 31, 2001. Two weeks
                        UNITED STATES v. MOHR                           5
later, the jury returned a guilty verdict against Mohr on the § 242
charge and acquitted Delozier on the conspiracy charge. The district
court subsequently sentenced Mohr to 120 months imprisonment.

                                   II.

  Mohr first and principally contends that the district court erred in
admitting, pursuant to Federal Rule of Evidence 404(b), evidence of
two subsequent acts of her intentional misuse of a police dog.

   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" but may be admissible for
"other purposes, such as proof of . . . intent." The rule "is understood
as a rule of inclusion," United States v. Queen, 132 F.3d 991, 994 (4th
Cir. 1997), and covers evidence of both prior and subsequent acts. See
United States v. Germosen, 139 F.3d 120, 128 (2d Cir. 1998) ("The
fact that the evidence involved a subsequent rather than prior act is
of no moment."); United States v. Hadaway, 681 F.2d 214, 217 (4th
Cir. 1982) ("[S]ubsequent conduct may be highly probative of prior
intent.").

   A court weighs the admissibility of Rule 404(b) evidence in a four-
part test. Queen, 132 F.3d at 997. The evidence must be (1) relevant
to an issue, such as an element of the offense; (2) necessary "in the
sense that it is probative of an essential claim or an element of the
offense"; (3) reliable; and (4) admissible under Federal Rule of Evi-
dence 403, in that its prejudicial nature does not "substantially out-
weigh[ ]" its probative value. Id. Rule 403 requires exclusion of
evidence "only in those instances where the trial judge believes that
there is a genuine risk that the emotions of the jury will be excited
to irrational behavior, and that this risk is disproportionate to the pro-
bative value of the offered evidence." United States v. Powers, 59
F.3d 1460, 1467 (4th Cir. 1995) (internal quotation marks omitted).

  We review the district court’s decision as to admissibility of evi-
dence for an abuse of discretion, and will not find an abuse unless a
decision was "arbitrary and irrational." United States v. Weaver, 282
F.3d 302, 313 (4th Cir. 2002). We afford the district court wide dis-
6                       UNITED STATES v. MOHR
cretion in "determining whether evidence is unduly prejudicial."
United States v. Aramony, 88 F.3d 1369, 1377 (4th Cir. 1996).

                                   A.

   The first evidence of Mohr’s misuse of a police dog involved her
release of a police dog on Kheenan Sneed, a 16-year-old African-
American boy. Sneed, his mother, and Mohr all testified about the
incident.

   Their testimony revealed that on the evening of August 3, 1997,
Mohr and her police dog tracked a possible suspect who had run from
police after committing a commercial burglary in Oxon Hill, Mary-
land. In a nearby residential neighborhood, Sneed slept in a neigh-
bor’s backyard hammock. Sneed was awakened by a dog biting his
leg and pulling him out of the hammock, and a female officer striking
him in the back of his head and on his right shoulder with a flashlight
or baton. The dog remained on Sneed’s leg after he was handcuffed.
Sneed urinated on himself while the dog bit him. He testified that he
did not hear any type of K-9 warning prior to the dog bite. Sneed also
testified that he never tried to run away from the officer, never threat-
ened her, and never resisted in any way. He was not charged as a
result of the incident.

   Mohr testified that she believed Sneed was the suspect based on
her dog’s track of the suspect’s scent. When she saw Sneed in the
hammock, she gave two K-9 warnings, received no response, and
then released the dog. She testified that Sneed struggled with the dog
and attempted to injure him, so she struck Sneed with her flashlight
to keep him from injuring the dog. When another officer then told her
that Sneed might not be the suspect, Mohr took the dog "off right
away and backed off."

   Mohr does not contest the reliability of the evidence relating to the
Sneed incident. Moreover, the incident was certainly relevant; both
the Sneed incident and the incident at issue in the instant case
involved Mohr’s unreasonable release of her police dog. See Queen,
132 F.3d at 997 ("[T]he more similar the prior act is . . . to the act
being proved, the more relevant it becomes."). In fact, in her appellate
brief, Mohr recognizes the relevance of the Sneed evidence, arguing
                         UNITED STATES v. MOHR                           7
(in support of her contention that its admission unfairly prejudiced
her) that the Sneed incident "bears . . . close similarity to the situation
involved in this case."

   Mohr does, however, strongly challenge the necessity of this evi-
dence. The government maintains that it was necessary to prove an
element of the § 242 offense, namely Mohr’s willful release of her
police dog on Mendez. In this case, to demonstrate a violation of
§ 242, the government had to establish, inter alia, that Mohr acted
(1) willfully, that is with "the particular purpose of violating a pro-
tected right made definite by the rule of law" or "recklessly disregard-
[ing] the risk" that she would do so (2) under color of law, (3) to
deprive Mendez of a right protected by the Constitution of the United
States. United States v. Johnstone, 107 F.3d 200, 210 (3d Cir. 1997)
(interpreting Screws v. United States, 325 U.S. 91 (1945)); see United
States v. Brown, 250 F.3d 580, 584 (7th Cir. 2001); United States v.
Cobb, 905 F.2d 784, 787 (4th Cir. 1990). Thus, the government
clearly bore the burden of proving, beyond a reasonable doubt, that
Mohr released her dog, willfully intending to deprive Mendez of his
constitutional right to be free of excessive force. Evidence of Mohr’s
release of her police dog on Sneed was probative of willfulness
because it suggested that, on at least one other occasion, Mohr used
her police dog in a way that recklessly disregarded the risk that her
actions would violate a citizen’s right to be free from the use of
excessive force.

   Nevertheless, Mohr argues that evidence of the Sneed incident was
not necessary to establish her willful intent because the government
had "a mass of [other] evidence" of intent, including testimony as to:
the suspects’ surrender before Mohr released the dog, the blatant
impropriety of Delozier’s request that Bonn allow the dog "to get a
bite," prevailing practices on use of police dogs, and Mohr’s alleged
efforts to lie and cover-up any wrongdoing.3 The problem with this
argument is that Mohr specifically disputed her intent at trial. She her-
  3
   Mohr also argues that she confessed at trial that she "intentionally
released her dog." This argument misapprehends the specific intent
requirement of § 242. She only testified that she made the decision to
release the dog rather than doing so at Delozier’s request. She certainly
did not confess that she willfully released the dog on Mendez.
8                       UNITED STATES v. MOHR
self testified that she released the dog on Mendez based on her train-
ing and her view that it was reasonable and justified given her
perception that Mendez was attempting to flee. In light of the govern-
ment’s heavy burden of proving, beyond a reasonable doubt, that
Mohr released her dog on Mendez with the "particular purpose" of
violating or in "reckless[ ] disregard" of Mendez’s right to be free
from unreasonable force, the district court clearly did not abuse its
discretion in finding the Sneed incident evidence necessary.

   Mohr’s final contention with respect to the Sneed evidence is that,
even if relevant, reliable, and necessary, it should have been sup-
pressed under Rule 403 because it unfairly prejudiced her by "paint[-
ing]" her as a "racist" white police officer, releasing her "attack dog"
on a "defenseless African-American child." Actually, we believe that
the potency of this evidence lay in its graphic demonstration that
Mohr unreasonably released her police dog on an innocent, clearly
unresisting young person — regardless of the race or sex of that per-
son. If believed, such evidence would, of course, severely damage
Mohr’s defense, but "[u]nfair prejudice under Rule 403 does not
mean the damage to a defendant’s case that results from the legitimate
probative force of the evidence." 2 Jack B. Weinstein & Margaret A.
Berger, Weinstein’s Federal Evidence, § 404.21[3][b] (Joseph M.
McLaughlin, ed., 2d ed. 2002) (emphasis in original). Indeed, our
adversarial system depends on opposing parties offering evidence that
will strengthen their respective positions and damage that of their
opponents.

   Rather, Rule 403 only requires suppression of evidence that results
in unfair prejudice — prejudice that damages an opponent for reasons
other than its probative value, for instance, an appeal to emotion, and
only when that unfair prejudice "substantially outweigh[s] the proba-
tive value of the evidence." Id. (emphasis in original); see also United
States v. Grimmond, 137 F.3d 832, 833 (4th Cir. 1998). In this case
it does not seem to us that any unfair prejudice resulted from the fact
that Sneed happened to be an African-American and that the govern-
ment noted his race in its opening statement. And, in any event, any
possible unfair prejudice certainly did not "substantially outweigh"
the probative value of the Sneed evidence.

   This is especially so given the instructions provided the jury by the
district court. The court explained that "Mohr [was] not on trial for
                       UNITED STATES v. MOHR                         9
committing any act not alleged in the indictment," and that evidence
of other bad acts may not be used as "a substitute for proof that she
committed the crime charged" or as proof of "criminal personality or
bad character" but rather was only relevant in determining if Mohr
acted "knowingly and intentionally" and not because of "mistake,
accident or other innocent reason." Such a careful limiting instruction
significantly ameliorated any possible unfair prejudice here. See Pow-
ers, 59 F.3d at 1468 (noting that "cautionary or limiting instructions
generally obviate" prejudice).

                                  B.

   Mohr also contends that the district court abused its discretion in
admitting testimony regarding her threat to release her police dog on
Jocilyn Hairston’s "black ass" if Hairston lied about the whereabouts
of her fugitive brother. Hairston, her mother, and Mohr testified about
the incident.

   In July 1998, Hairston, an African-American woman about thirty-
seven years old, and her mother lived in Capitol Heights, Maryland.
One evening, some time after 11:30 p.m, three officers arrived at
Hairston’s home looking for her brother, who had violated his proba-
tion in California. Mohr, accompanied by a police dog, was one of
these officers. After the officers learned from Hairston that her
brother was not there, one of the male officers asked if they could
search the house; Hairston replied "sure." While they searched, Mohr
and the dog remained on the top step of the stoop and Hairston stood
in the doorway of the house. Hairston asked Mohr if she could move
because she was "scared of the dog," who was jumping up. Mohr said
no. Hairston testified that Mohr then said: "I’m going to let him in.
He’s going to bite your black ass and your brother if I find out he’s
in there." Mohr’s tone of voice and demeanor were "nasty" when she
"said the comment about the black ass."

   In her testimony, Hairston’s mother identified Mohr as the officer
with the dog and confirmed her daughter’s testimony regarding the
"black ass" comment. Mohr testified that she did not recognize Hair-
ston or her mother and that she had only a "vague recollection of the
call for service, but . . . nothing stuck out from that call."
10                       UNITED STATES v. MOHR
   We again apply the four factors for admissibility of evidence under
Rule 404(b). As with the Sneed evidence, Mohr does not contest the
reliability of the Hairston evidence. With regard to relevance, she
argues that the Hairston incident and the release of the dog on
Mendez are not sufficiently similar because Mohr never released her
dog on Hairston. But the purpose of the 404(b) evidence in this case
was to establish that Mohr possessed the requisite state of mind —
willfulness — when she released her dog on Mendez. Mohr’s threat
to release her dog on an unresisting, innocent citizen goes to that
essential question of willfulness, regardless of whether she actually
released the dog. See Queen, 132 F.3d at 996 ("[S]imilarity may be
demonstrated through physical similarity of the acts or through the
defendant’s indulging [her]self in the same state of mind in the perpe-
tration of both the extrinsic offense and charged offenses.") (internal
quotation marks omitted)). Thus, the evidence was relevant. We also
conclude, for the reasons discussed with regard to the Sneed incident,
that evidence of the Hairston incident was necessary and not unfairly
prejudicial.

   We do address, however, one specific argument that Mohr raises
as to the asserted prejudicial nature of the Hairston evidence. Mohr
contends that, even if the district court properly found the evidence
admissible, the court should have redacted any reference to Hairston’s
"black ass" as "extremely prejudicial." Of course, a district court
should, when possible, eliminate inflammatory language. In this
instance, however, we agree with the district judge that the "black
ass" portion of Mohr’s threat cannot be reasonably separated from the
threat itself.4
  4
    We also reject Mohr’s contention that the government’s connection in
its opening statement between the "black ass" comment and "how Steph-
anie Mohr’s mind works" pertained to alleged racism by Mohr and was,
therefore, unfairly prejudicial. It is clear from the context that the gov-
ernment intended to draw a connection for the jury between Mohr’s
unjustified threat to release the dog on Hairston and her willful release
of the dog on Mendez. Thus, the prosecutor stated, "there is going to be
additional evidence that this was no mistake or no accident on the part
of Officer Mohr that night. . . . [Y]ou’re going to hear about another inci-
dent that speaks volumes about Officer Stephanie Mohr’s state of mind,
about how she thinks and what she was thinking on that night . . . . And
                          UNITED STATES v. MOHR                            11
   Without that phrase, Mohr could argue that Hairston misunder-
stood her or that she merely issued a legitimate warning. Indeed, in
her appellate brief, Mohr argues precisely this: "[A]ll Ms. Mohr did
— sans the alleged racism — was warn that she would release the dog
if and only if it were established that the residents were lying to
police, that they were harboring a known fugitive who was suspected
of armed bank robbery." The "black ass" portion of Mohr’s remark
could not be redacted from the remainder of it without changing the
meaning of that remark. Therefore, the district court did not abuse its
discretion in not redacting it.

                                     C.

   Mohr makes two additional general challenges to the 404(b) evi-
dence that require brief discussion. She maintains that after the gov-
ernment failed to obtain her conviction for violation of § 242 at the
first trial, it decided to "play the race card" to "improperly inflame the
passions of the jury" by seeking admission of evidence of bad acts
involving African-Americans, which had not been part of its case at
the first trial, and that the district court improperly acceded to the
government’s request and allowed "irrelevant references to racism to
infect the trial." Mohr also contends that the district court admitted
"too much" Rule 404(b) evidence. The record provides no support for
either argument.

   Prior to the second trial, the government did file a written motion
to admit evidence, which had not been admitted at the first trial, of

then she says if your brother is here, I’m going to put the dog on him,
and I’m going to put the dog on your black ass, too. . . . That is how
Stephanie Mohr’s mind works. That’s how you know that what happened
in the back of Sligo Press on September 21st, 1995 was no accident. It
was no mistake." We also do not find that Mohr’s question to Hairston,
"[I]s that what you people do for a living, waving guns in people’s
face[s]," was unfairly prejudicial, especially in light of the fact that Hair-
ston responded in a way that interpreted the "you people" as a reference
to her family rather than to a racial group. Hairston testified that she
responded that both she and her mother worked and that "[i]f [her]
brother choose[s] to make a mistake . . . it doesn’t reflect on [her] or
[her] family."
12                        UNITED STATES v. MOHR
six Rule 404(b) incidents in which Mohr "intentionally made
improper use of her police canine." But the government offered an
entirely legitimate justification for this request — this evidence was
necessary to prove wrongful willfulness in Mohr’s handling of the K-
9 with respect to Mendez, because, at the first trial, Mohr had offered
the defense that release of the dog on Mendez was reasonable under
the circumstances and done without criminal intent. Although oppos-
ing the government’s motion, Mohr acknowledged in her opposition
that the "[g]overnment correctly asserts that defendant Mohr raised
the issues of reasonableness and lack of criminal intent in the first
trial and will likely do so in the next." After consideration of these
arguments, the experienced district judge, who had also presided over
the first trial, found that "based on the first trial, . . . there is a neces-
sity for the [g]overnment to utilize similar incident evidence in order
to demonstrate intent" given the "very big dispute as to the circum-
stances under which" Mohr made the decision to release the dog. As
we have already held, the district court certainly did not abuse its dis-
cretion in so holding. Furthermore, that the other similar incidents in
some way involved African-Americans does not make the govern-
ment guilty of "playing the race card."

   Perhaps more importantly, the district court’s careful treatment of
this evidence eliminated the possibility of such a strategy even if that
had been the government’s intent. After examining written materials
relating to the six proffered incidents and conducting a pre-trial hear-
ing, the district court permitted the government to introduce evidence
of only two of the six incidents — the Sneed and Hairston incidents
— and reserved ruling on a third incident, which the government did
not subsequently seek to admit. The Sneed evidence did not demon-
strate racism on Mohr’s part, just willfulness. A portion of the Hair-
ston evidence did suggest racism but that portion could not be elimi-
nated without depriving the Hairston evidence of its probativeness. In
any event, that testimony did not "infect" the trial. Rather, during the
eleven-day trial, only two witnesses briefly testified for the govern-
ment about each of the incidents, and Officer Mohr testified in her
own defense and provided the jury with her version of the incidents.
Moreover, as noted within, the district court carefully instructed the
jury as to the limited relevance of this evidence. Given this record, we
cannot conclude that the district judge admitted "too much"
                        UNITED STATES v. MOHR                         13
Rule 404(b) evidence or allowed the prosecution to inflame the jury
with unnecessary evidence of Mohr’s alleged racism.

                                  III.

   Mohr also asserts that the testimony of the government’s rebuttal
expert exceeded that allowed under the Federal Rules of Evidence.
Although the government maintains that we should review Mohr’s
challenge to certain aspects of the expert testimony for plain error, we
believe that Mohr adequately preserved all of her objections to the
expert testimony. Accordingly, we review the district court’s deci-
sions with respect to admission of the expert testimony for abuse of
discretion. Martin v. Cavalier Hotel Corp., 48 F.3d 1343, 1358 (4th
Cir. 1995).

                                   A.

   Paul Mazzei, Mohr’s basic training officer, now the owner of a law
enforcement training and consulting group and the deputy director of
the Prince George’s Municipal Police Academy, testified as the first
defense witness. He recounted what he had taught Mohr about the
"use of force continuum and reasonable force and police safety." He
explained that use of a K-9 would be considered "less lethal force"
and "would fall in the same area" as "an intermediate weapon," such
as a baton.

   Mazzei also testified about Mohr’s training as to specific arrest sce-
narios. For example, an evening burglary in progress at a commercial
location was to be considered "a very high-risk situation," in which
a suspect’s failure to comply with commands "increases the risk," and
a suspect’s waistband area "is one of the highest risk areas where
individuals could secrete firearms." She was further taught that when
a suspect, "in a moderate-to-high-risk situation," drops his hands to
the area of the waistband, it is an "extremely hazardous time" and
officers must "evaluate the situation and take control as quickly as
possible with the level of force that would be most reasonable to do
so." Throughout his testimony, Mazzei used the terms "reasonable"
and "totality of the circumstances" and discussed a "reasonable" use
of force. Mohr then testified in her own defense and provided the
14                      UNITED STATES v. MOHR
details of her K-9 training, including the view that a K-9 is one level
below lethal force or use of a firearm.

    James Fyfe, a New York City police officer for sixteen years and
now a professor of criminal justice and use-of-force consultant to
police departments, testified for the government in rebuttal. Like
Mazzei, Fyfe placed a K-9 on the use of force continuum, but he put
a K-9 "just below deadly force" and above an impact weapon. He
opined that, based on Mohr’s trial testimony, her release of the K-9
"was not in accord with prevailing police practices in 1995." His
opinion was based on "tak[ing] into account the totality of the circum-
stances and the idea that police should use no more force than is nec-
essary, reasonably necessary, in the totality of the circumstances."
Fyfe then discussed a number of the factors in Mohr’s version of
events and concluded that "in those circumstances, it seems to me that
the use of the dog on such a quick movement was inappropriate
because there were less drastic ways of apprehending these folks
. . . who had given no indication that they were armed in any way."
He further explained: "[W]here you’re facing a potential foot race
between the dog and a human being, you have plenty of time to give
the warning because the dog is certainly going to outrun the human
being and apprehend him. So I don’t think this was a split-second
decision. . . . [T]here’s no reason why you can’t give a [K-9] warning
like that and still have plenty of time for the dog to apprehend the
individual."

                                  B.

   Mohr acknowledges that Federal Rule of Evidence 704 permits
expert testimony "that embraces an ultimate issue to be decided by a
trier of fact" if the testimony is "otherwise admissible," Fed. R. Evid.
704(a), but she contends that Fyfe’s testimony was not "otherwise
admissible" because it did not assist the jury, as required by Federal
Rule of Evidence 702, and because it exceeded the scope of proper
rebuttal. Our decision in Kopf v. Skyrm, 993 F.2d 374 (4th Cir. 1993),
given the record in this case, forecloses Mohr’s challenges to Fyfe’s
testimony. In Kopf, a § 1983 excessive force action, we reversed the
district court’s exclusion of expert testimony that an officer’s use of
                        UNITED STATES v. MOHR                          15
his police dog was "unreasonable and "violated accepted police prac-
tices." Id. at 378.5

   Mohr suggests that Kopf only resolves the question of whether any
expert testimony on use of police dogs is permissible; she acknowl-
edges the admissibility of Fyfe’s testimony as to "where a K-9 falls
on the use of force continuum" but insists that, notwithstanding Kopf,
much of Fyfe’s remaining testimony was inadmissible because it "im-
permissibly told the jury what decision to reach." Specifically, Mohr
challenges Fyfe’s testimony that: (1) Mohr violated "prevailing police
practices nationwide in 1995"; (2) a police officer should use no more
force than "reasonably necessary, in the totality of the circumstances";
(3) Mohr’s release of the dog was "inappropriate"; (4) Mohr had
"plenty of time to give [a K-9 warning]"; and (5) there was "no rea-
son" not to give a warning. Mohr contends Fyfe’s "prevailing police
practices" opinion was not proper rebuttal and that none of these opin-
ions assisted the jury, which needed no expert to aid it in resolving
the common sense issue of what is reasonable force.

   Mohr reads Kopf too narrowly. In Kopf, we specifically rejected the
contention that expert testimony of the sort Mohr challenges would
not properly assist a jury. We noted that Rule 702 permits an expert
witness to testify "in the form of an opinion or otherwise" if "special-
ized knowledge will assist the trier of fact to understand the evidence
or to determine a fact in issue." 993 F.3d at 377 (quoting Fed. R.
Evid. 702). We explained that an "objective reasonableness" test like
that used to determine the reasonableness of force "implies the exis-
tence of a standard of conduct," and where that standard is defined,
not by a reasonable person, but by a reasonable officer, "it is more
likely that Rule 702’s line between common and specialized knowl-
edge has been crossed." Id. at 378.

   Although we held that the facts of every case, especially the type
of force involved, would determine whether expert testimony could
  5
   "Because 18 U.S.C. § 242 is merely the criminal analog of 42 U.S.C.
§ 1983, and because Congress intended both statutes to apply similarly
in similar situations, our civil precedents are equally persuasive in this
criminal context." United States v. Cobb, 905 F.2d 784, 788 n.6 (4th Cir.
1990).
16                      UNITED STATES v. MOHR
assist the jury, we specifically found expert testimony on police dogs
admissible because the "train[ing] and use" of a police dog are "ob-
scure skills." Id. at 379. We also did not foreclose the expert’s testi-
mony, under Rule 704(a), that the use of the police dog in that case
was "unreasonable" and "violated accepted police practices." Id. at
378-79. Finally, we held that the district court abused its discretion in
not permitting the expert to rebut testimony offered by the officer that
his actions were reasonable because the purpose of a police dog is "to
encounter a dangerous situation in lieu of officers," with the expert
view that "the purpose of a police dog is to locate suspects, not to
apprehend or bite them" and that, given the number of officers on the
scene, it "was improper" for the officer to "permit the dog to bite and
cause serious injury." Id. at 378.

   In this case, Mazzei and Mohr testified extensively as to her train-
ing, their view of the K-9 and use of force, and the reasonableness of
Mohr’s release of her dog in light of the arrest factors. Given this tes-
timony, the district court did not abuse its discretion in permitting the
government to offer Fyfe’s rebuttal testimony, which closely mirrored
that discussed in Kopf. Specifically, the court did not abuse its discre-
tion in allowing Fyfe to testify that Mohr’s use of her police dog was
"was not in accord with prevailing police practices in 1995" and to
rebut the import of the combined testimony of Mohr and her training
officer that her actions were both consistent with her training and rea-
sonable based on the various factors surrounding the arrest.

                                  IV.

   Finally, Mohr argues that Dennis Bonn, on redirect examination,
should not have been permitted to (1) read to the jury a prior consis-
tent statement that he made to the FBI because he had a pre-existing
motive to lie and (2) explain his motivation for making that statement,
namely his fear that he would fail an upcoming polygraph examina-
tion. Mohr contends that this testimony violated Federal Rule of Evi-
dence 801(d)(1)(B), which permits a witness to testify to prior
consistent statements as rebuttal to a charge "of recent fabrication or
improper influence or motive."

                                   A.

   During the government’s investigation, Bonn initially gave incon-
sistent statements to the FBI and failed to mention his verbal assent
                        UNITED STATES v. MOHR                         17
to Delozier’s request that the dog "get a bite." However, Bonn ulti-
mately admitted the exchange to the FBI in a short (twenty-nine line)
written statement. Prior to trial, the government notified the defense
and the district court that, depending on defense opening statements
and cross-examination of Bonn, it might seek to elicit testimony on
redirect about Bonn’s motivation for making the admission in the
written statement. The government proffered that Bonn would testify
that he admitted his own involvement because he had acceded to the
FBI request that he take a polygraph and believed that he would fail
the polygraph unless he made the admission. In fact, Bonn did not
ultimately take a polygraph examination.

   On direct examination, the government did not question Bonn
about the written statement or show it to the jury. Mohr’s counsel,
however, showed Bonn the written statement during cross-
examination, questioned him about it, and quoted some of the state-
ment to Bonn, asking him to verify that the statement was his lan-
guage, that it was voluntary, and that Bonn had reviewed "every
word" of the statement and signed it. Mohr’s counsel also suggested
improper motives for Bonn to fabricate the admission in the statement
including (1) a provision in his plea agreement that shielded him from
prosecution for another offense; (2) a 40-day delay in pleading guilty
so that he would not face deferral of his pension benefits for 10 years;
(3) being permitted to plead guilty to a lesser offense; and (4) the pos-
sibility of a downward departure for substantial assistance.

   The district court permitted the government on redirect to ask Bonn
to explain why he admitted his exchange with Delozier in the written
statement. In doing so, the district court noted that the government
provided "advance warning" about the issue in order to allow the
defense to avoid it entirely, but that Mohr’s counsel had "opened with
the witness" the contents of the statement by showing it to him on
cross-examination. On redirect, in response to the government’s ques-
tion as to why he made the admission, Bonn explained that he decided
"to come clean" because he "knew the polygraph wasn’t going to
come up well." The government then had Bonn read the statement to
the jury. On recross, Mohr’s counsel elicited testimony from Bonn
that, at the time he made the written statement, he knew polygraphs
were not admissible in court, were "inherently unreliable," and that he
made the decision not to take the polygraph. Mohr’s counsel also elic-
18                      UNITED STATES v. MOHR
ited that some portions of the written statement itself were inconsis-
tent with Bonn’s trial testimony.

                                   B.

   Mohr maintains that Bonn’s reading of his written statement to the
jury and testimony about it on redirect violated Rule 801(d)(1)(B)
because Bonn made the prior consistent statement after he had a
motive to lie. The flaw in this argument is, as we explained in United
States v. Ellis, 121 F.3d 908, 919 (4th Cir. 1997), that Rule
801(d)(1)(B) is not "the only possible avenue for admitting" prior
consistent statements. Adoption of Rule 801(d)(1)(B) did not elimi-
nate the admissibility of prior consistent statements under the Doc-
trine of Completeness, that is "when one party has made use of a
portion of a document, such that misunderstanding or distortion can
be averted only through presentation of another portion, the material
required for completion" is admissible. Id. at 921 (internal quotation
marks omitted). In this case, the district court properly permitted
Bonn to read his short statement to the jury during redirect because
defense counsel had extensively cross-examined Bonn about the doc-
ument and used a "portion" of it without permitting the jury to see it
or Bonn to explain it. Id. Allowing Bonn to read the statement on
redirect "averted" possible "misunderstanding or distortion." Id. As
the district court noted, although the government provided "advance
warning" about the issue in order to allow the defense to avoid it
entirely, Mohr’s counsel failed to heed the warning and instead
"opened the door" by showing the statement to Bonn and cross-
examining him about it.

   Mohr also maintains that the district court abused its discretion,
under Rule 403, in permitting Bonn to explain, on redirect examina-
tion, that concern over an impending polygraph examination caused
him to make the written statement. Again, we agree with the district
court that Mohr "opened the door" to Bonn’s testimony on redirect by
suggesting, in cross-examination, other improper motives for Bonn to
make the statement, and thus the district court did not abuse its discre-
tion in permitting the testimony. See United States v. Williams, 106
F.3d 1173, 1177 (4th Cir. 1997) (finding no abuse of discretion where
district court permitted hearsay testimony on redirect examination
                       UNITED STATES v. MOHR                      19
because defense opened the door through line of questioning in cross-
examination).

                                 V.

   This charged, notorious, highly publicized case requiring two full
trials demanded good judgment and a steady hand from the district
court. Our careful consideration of both the record and Mohr’s appel-
late arguments persuade us that Mohr received precisely that. The
judgment of the district court is in all respects

                                                        AFFIRMED.
