                            PUBLISHED

UNITED STATES COURT OF APPEALS
                FOR THE FOURTH CIRCUIT


UNITED STATES OF AMERICA,              
                 Plaintiff-Appellee,
                 v.                               No. 00-4754
OTIS LEE WEAVER, JR.,
             Defendant-Appellant.
                                       
           Appeal from the United States District Court
            for the District of Maryland, at Greenbelt.
                 Peter J. Messitte, District Judge.
                          (CR-99-67-PJM)

                      Argued: November 2, 2001

                      Decided: February 28, 2002

      Before NIEMEYER and LUTTIG, Circuit Judges, and
         Frank J. MAGILL, Senior Circuit Judge of the
      United States Court of Appeals for the Eighth Circuit,
                     sitting by designation.



Affirmed by published opinion. Senior Judge Magill wrote the opin-
ion, in which Judge Niemeyer and Judge Luttig joined.


                             COUNSEL

ARGUED: Daniel William Stiller, Assistant Federal Public
Defender, Greenbelt, Maryland, for Appellant. Gina Laurie Simms,
Assistant United States Attorney, UNITED STATES ATTORNEY’S
OFFICE, Greenbelt, Maryland, for Appellee. ON BRIEF: James
2                      UNITED STATES v. WEAVER
Wyda, Federal Public Defender, Greenbelt, Maryland, for Appellant.
Stephen M. Schenning, United States Attorney, UNITED STATES
ATTORNEY’S OFFICE, Greenbelt, Maryland, for Appellee.


                               OPINION

MAGILL, Senior Circuit Judge:

   On February 22, 1999, a federal grand jury sitting in Maryland
returned a three-count indictment charging Otis Lee Weaver, Jr., with
bank robbery pursuant to 18 U.S.C. § 2113(a)(f), in connection with
three robberies that occurred on December 11, 1997, January 29,
1998, and March 5, 1998, in Maryland. On August 1, 2000, the case
went before a jury. On August 15, 2000, the jury returned its finding
of guilty on all three counts charged in the indictment. Weaver was
sentenced to 110 months imprisonment and three years supervised
release and required to pay $8168 in restitution and three $100 special
assessments. This appeal follows.

   In particular, Weaver appeals a decision of the district court deny-
ing his motion to suppress evidence that was obtained as a result of
a consensual encounter between himself and law enforcement offi-
cials. Weaver also appeals the district court’s admission of certain
"other crimes" evidence pursuant to Rule 404(b) of the Federal Rules
of Evidence. Weaver’s final contention is that the district court vio-
lated his due process rights at trial by "assisting" the prosecution, war-
ranting a new trial. We reject Weaver’s claims and accordingly affirm
the district court.

                                    I.

   The underlying facts are basically undisputed. The first robbery
charged in the indictment occurred on Thursday, December 11, 1997,
at a branch of the American Federal Savings Bank in Rockville,
Maryland. At about 3:30 p.m., Cassandra Powell, the bank manager,
saw a man, later identified as Weaver, enter the bank and survey his
surroundings. Powell noticed that the man kept his right hand in his
pocket as he approached Rama Dewan, a teller. Believing that a rob-
                      UNITED STATES v. WEAVER                        3
bery was taking place, Powell walked toward the robber holding up
the keys to the teller drawer, signaling to him that she was the one
person able to provide him access to the cash contained in the drawer.
As Powell approached, the robber handed Dewan a white plastic bag
and instructed Dewan in an angry, agitated tone to "give me the
money" and to "put it in the bag." The robber also warned Dewan not
to pull any alarms. After receiving the keys from Powell, Dewan
opened the drawer and put approximately $2000 into the bag and
handed the bag back to the man, who then walked out of the bank
without incident.

   When the police arrived at the bank after the robbery, Powell and
Tammy Tulloch, another bank employee, each described the robber.
Powell described the robber as a thin black male, approximately six
feet tall and wearing a navy knit cap, a burgundy Tommy Hilfiger
windbreaker with cursive writing on it, and baggy blue jeans. Tulloch
described the robber as a dark-complected young black male, skinny,
weighing 140 to 150 pounds, and wearing a dark knit cap, a burgundy
pullover with thin white cursive writing, and baggy blue jeans. After
reviewing photos of Weaver in July of 1998, both Tulloch and Powell
identified Weaver as the robber.1

   The second robbery took place at the same Rockville, Maryland
bank on Thursday, January 29, 1998, at approximately 2:30 p.m.,
when a man, later identified as Weaver, walked into the bank,
approached Dewan, handed her a brown paper bag, and demanded
money. As the robber approached Dewan, he kept his hand in his
pocket. Both Dewan and Erin Funk, the bank manager, thought that
the man had a gun. The robber, once again, spoke in a loud and agi-
tated tone, and demanded that Dewan give him the money from the
drawer. Dewan opened the drawer and put about $2000 into the bag.
The robber took the money and left without incident.

   At trial, Dewan was unable to identify Weaver as the robber, nor
could she identify him when shown a photo array. In fact, Dewan
thought the robber was a person other than Weaver. Funk described
the robber to the police as being a young black male who was approx-
  1
   Dewan, who testified that she was too scared to look at the robber’s
face during the incident, could not identify Weaver.
4                     UNITED STATES v. WEAVER
imately 5’10" tall and skinny, and as having a little and round head
and as wearing a tannish-brown knit hat, large dark-framed eye-
glasses, a dark blue jacket, dark jeans, and white sneakers. She identi-
fied Weaver as the robber from a photo array.

   A third robbery occurred on Thursday, March 5, 1998, this time at
a Maryland Federal Savings & Loan Branch in Bethesda, Maryland.
On at least three or four occasions during the week before the rob-
bery, bank employees Stephanie Yarmas, Catina Sapp, Rebecca Coo-
per, and Hilde Kochanek observed Weaver coming into the bank and
asking for a loan application. Three of the employees testified that
Weaver wore the same dirty jean jacket and blue jeans each time he
came into the bank. Also, all four employees, on some occasions,
recall Weaver wearing large eyeglasses.

   At about 2:30 p.m., on March 5, a man, later identified as Weaver,
entered the bank with a loan application in his hand. After handing
the loan application to Yarmas, the individual placed a hand on her
shoulder and put something that felt like a gun against her back. The
robber directed Yarmas toward the teller line door and threatened to
shoot her at one point. At that point, Sapp and Cooper helped Yarmas
open the door. The robber then directed both Sapp and Cooper to
empty the drawers into a white plastic shopping bag that he provided
for them. Sapp, Yarmas, and Cooper all testified that during the rob-
bery Weaver kept one of his hands in his jean jacket pocket. Both
Sapp and Yarmas placed dye packs and bait money into the bag.
When the robber received the money, he thanked the employees, told
them to "have a nice day," and calmly left the bank.

   When police responded at the bank, Sapp described the robber as
a 25-year-old, medium-complected black man, about 5’5" tall, and
weighing approximately 150 pounds. Sapp further described the rob-
ber as being unshaved and wearing a yellow and blue ski hat, brown
eyeglasses, a blue jean jacket with dried mud on it, a red and white
"Guess" shirt, jeans, and white sneakers. Cooper told the police that
the robber wore a blue hooded sweatshirt, but at trial, more than two
years after the robbery, she also recalled telling the police that the
robber wore a jean jacket and was 5’5" tall. When shown photo
arrays, Sapp and Cooper identified Weaver as the robber. At trial,
Cooper, Sapp, and Yarmas identified Weaver in court as the robber.
                       UNITED STATES v. WEAVER                         5
   After the three Maryland robberies, on June 10, 1998, Weaver, a
black male standing about six feet tall and weighing 180 pounds,
entered a branch of the First Union Bank in Springfield, Virginia, and
robbed the bank.2 Weaver was wearing a black Baltimore Ravens cap,
large brown eyeglasses, navy blue sweat pants, and a navy and black
flannel shirt. With one hand in his pocket, Weaver accosted a bank
employee by pressing a hard object into her back and directing her to
the teller area. Once at the teller area, Weaver pulled out a white plas-
tic bag and told the teller to put the money into the bag or risk being
shot. Weaver also told the teller not to put any bait money into the
bag. Weaver made a similar demand of another teller, and after
obtaining the bag containing approximately $1500, he told the tellers
to "have a nice day" and walked out of the bank. This robbery was
not charged in the indictment for the three Maryland robberies.

   Seven days after the Virginia robbery, on June 17, 1998, Weaver
was arrested in Virginia as a suspect in the Virginia robbery. That
day, the authorities received a report about a suspicious individual at
a bank whom the bank teller believed matched the description of the
person on a "wanted poster" connected to the June 10 robbery. The
teller’s report described a short-haired black male, about six feet tall,
weighing approximately 175 pounds, and wearing glasses and a base-
ball hat. Officer Eric Leeds was on duty about one hundred yards
away from the location when he received the call. About five seconds
later, Officer Leeds saw Weaver, whom he believed fit the description
of the suspicious person. Notably, Officer Leeds had never seen the
wanted poster in question, nor does it appear from the record that he
had any prior knowledge of the robbery in question.

   Officer Leeds, who was armed and in uniform, approached and
made contact with Weaver. He asked Weaver if he could talk to him
and Weaver responded affirmatively. Officer Leeds explained to
Weaver that the police had received a call concerning a suspicious
person, and that Weaver matched the description of that person. Leeds
obtained Weaver’s driver’s license so that he could run a computer
check to see if Weaver had any arrest warrants. After determining that
there were no warrants for Weaver’s arrest, but before Leeds returned
  2
    This robbery constitutes the Rule 404(b) evidence that is at issue in
this case.
6                     UNITED STATES v. WEAVER
Weaver’s driver’s license, Leeds asked Weaver if he would accom-
pany him to a nearby bank. Weaver agreed and then Officer Leeds led
Weaver to a nearby NationsBank to verify the bank teller’s suspi-
cions. Once at NationsBank, Leeds discovered that he had taken Wea-
ver to the wrong bank.

   Next, Officer Leeds, who was still in possession of Weaver’s driv-
er’s license, asked Weaver if he would accompany him in his police
cruiser to another bank. Once again Weaver agreed, and pursuant to
standard police procedure Leeds patted down Weaver before he got
into the cruiser. After driving about one hundred yards to the second
bank, Leeds and Weaver met Officer Jones. Jones, who had also
heard the report, began questioning Weaver about why he was there.
While Weaver explained to Jones that he was there picking up job
applications, Officer Nicolo arrived at the scene and told Jones that
a woman inside the bank had just identified Weaver as the subject
depicted in the "wanted poster" in connection with the fourth robbery,
which occurred at the First Union Bank in Springfield, Virginia. Offi-
cer Jones, who also believed that Weaver matched a photograph that
he had seen the night before during roll call, remembered that the
information given the night before mentioned the possibility of a gun.
Out of concern for his and the other officers’ safety, Officer Jones
handcuffed Weaver and made a check for weapons. During the pat
down, Officer Jones felt a "hard object" on Weaver and asked Weaver
what he had in his pockets. Weaver’s pockets contained a pair of
large eyeglasses, a lighter, some keys, and a small quantity of mari-
juana. Upon finding the marijuana, Officer Jones told Weaver that he
was under arrest. The police recovered the eyeglasses and took a pho-
tograph of Weaver, which was later used to show to witnesses of the
other bank robberies. After viewing this photograph, five individuals,
from all three Maryland robberies charged in the indictment, indepen-
dently identified Weaver as the robber.

                                 II.

  Prior to trial, Weaver filed several motions, including a motion to
suppress all evidence seized from his person, namely his "oversized"
eyeglasses and the identification evidence. Following an evidentiary
hearing, the Maryland district court denied Weaver’s motion to sup-
press the eyeglasses and identification. The district court ruled that
                      UNITED STATES v. WEAVER                         7
Weaver’s Fourth Amendment rights were not violated because the
entire encounter between Weaver and the police was consensual.

   At trial, the government sought, over Weaver’s objection, to intro-
duce evidence relating to the bank robbery in Virginia, which Weaver
committed, under Federal Rule of Evidence 404(b), i.e., "other
crimes" exception. After an evidentiary hearing, the district court
agreed with the government and allowed evidence relating to the Vir-
ginia bank robbery to go before the jury, on all three counts charged
in the indictment, under Rule 404(b), as modus operandi evidence rel-
evant to establishing identity.

    Also at trial, the government attempted to establish the FDIC-
insured status of the Maryland Federal Savings & Loan through the
testimony of Hilde Kochanek, the branch manager of the Bethesda
bank involved in the robbery charged in Count Three of the indict-
ment. Over a defense objection and a motion to strike, Kochanek tes-
tified that, as of March 5, 1998, the funds in the bank were insured
by the FDIC. On cross-examination, Kochanek admitted that her
knowledge of FDIC coverage was premised on the presence of an
FDIC symbol in the bank window and the presence of a certificate on
the wall, and that she had no personal knowledge of the bank’s
insured status.

   Following Kochanek’s testimony, the district court asked the gov-
ernment what evidence it was offering to prove the FDIC-insured sta-
tus of Maryland Federal. The court, noting that the bank’s FDIC-
insured status constituted an element of the offense that the govern-
ment had to prove, said that it was not about "to let this case be tried
on the basis of a technicality."3 Accordingly, the court agreed to take
a "longer lunch hour" in order to allow the government to obtain the
necessary certification. However, the government was unable to
obtain the documentation on such short notice, so the government
requested a continuance so as to provide them an opportunity to
obtain the certificate of insurability. Weaver’s counsel strenuously
objected, arguing that the trial judge had improperly injected himself
  3
   The district court noted that "usually FDIC insurance is stipulated,"
and thus the court felt as though the government should be given an
opportunity to obtain the proper certification to prove insurability.
8                      UNITED STATES v. WEAVER
into the trial by instructing the government on how to cure a "fatal
defect" in its case.

   The court disagreed, and granted the continuance. Additionally, the
court explicitly refused to answer the government’s questions regard-
ing whether the evidence the government was going to offer, a certifi-
cate from the FDIC for American Federal Savings, would be
sufficient to establish FDIC-insured status. The court answered, "I
don’t think I can answer your question directly . . . which is what do
I think will be sufficient evidence? I mean I am not going to try your
case for you." The court also permitted Weaver to have a standing
objection to any witness or evidence relating to the bank’s insured
status. The trial continued that day, with the government introducing
the FDIC certificate for American Federal Savings.

   When the trial resumed ten days later, the government presented
the testimony of Joseph Yohe who offered testimony and evidence of
Maryland Federal’s FDIC-insured status. Ultimately, the jury con-
victed Weaver on all three counts of the indictment, and Weaver was
subsequently sentenced to 110 months imprisonment. The district
court entered final judgment on October 19, 2000, and a timely notice
of appeal was filed the next day. Our jurisdiction is premised upon 28
U.S.C. § 1291.

                                   III.

   We first address Weaver’s argument that he was unreasonably
seized for purposes of the Fourth Amendment when, as an interstate
traveler, he accompanied a uniformed and armed police officer, who
had retained his driver’s license, into a police cruiser. In light of these
facts, Weaver argues that the encounter between himself and Officer
Leeds was not consensual. It follows, Weaver argues, that if he was
in fact unreasonably seized, then all evidence that flows from this sei-
zure should have been suppressed by the district court. See Wong Sun
v. United States, 371 U.S. 471, 484-86 (1963). The government, how-
ever, argues that the interaction between Officer Leeds and Weaver
was consensual; therefore, the Fourth Amendment is not implicated.
The trial court, ruling from the bench, agreed with the government’s
reasoning that because Weaver was in "no way impeded physically by
holding his [identification] from him," and that because Weaver did
                       UNITED STATES v. WEAVER                         9
not ask for his driver’s license back, "he was not in that sense
detained." In reviewing the district court’s denial of a pretrial motion
to suppress evidence, we review the district court’s factual findings
for clear error, while all legal conclusions are reviewed de novo.
United States v. Sullivan, 138 F.3d 126, 131 (4th Cir. 1998).

   The Fourth Amendment to the United States Constitution provides
that the people shall "be secure in their persons, houses, papers, and
effects, against unreasonable searches and seizures . . . ." U.S. Const.,
amd. IV. The primary purpose of the Fourth Amendment is "‘to pre-
vent arbitrary and oppressive interference by enforcement officials
with the privacy and personal security of individuals.’" INS v. Del-
gado, 466 U.S. 210, 215 (1984) (quoting United States v. Martinez-
Fuerte, 428 U.S. 543, 554 (1976)). The Supreme Court has recog-
nized three distinct types of police-citizen interactions: (1) arrest,
which must be supported by probable cause, see Brown v. Illinois,
422 U.S. 590 (1975); (2) brief investigatory stops, which must be sup-
ported by reasonable articulable suspicion, see Terry v. Ohio, 392
U.S. 1 (1968); and (3) brief encounters between police and citizens,
which require no objective justification, see Florida v. Bostick, 501
U.S. 429, (1991). The case before us falls into the latter category.

   It is axiomatic that police may approach an individual on a public
street and ask questions without implicating the Fourth Amendment’s
protections. Bostick, 501 U.S. at 434; Florida v. Royer, 460 U.S. 491,
497 (1983) (plurality opinion). Without such an ability, law enforce-
ment officials would be neutralized to the point of being ineffective.
Some contacts that start out as constitutional may, however, at some
unspecified point, cross the line and become an unconstitutional sei-
zure. We are tasked with determining whether the encounter at issue
in this case, which without question started out as constitutional,
somehow crossed the not-so-bright line and blossomed into an uncon-
stitutional seizure.

   Generally speaking, a "seizure" warranting protection of the Fourth
Amendment occurs when, in view of the totality of the circumstances
surrounding the "stop," a reasonable person would not feel free to
leave or otherwise terminate the encounter. Sullivan, 138 F.3d at 133;
United States v. Lattimore, 87 F.3d 647, 653 (4th Cir. 1996) (en
banc). "Because the test is an objective one, its proper application is
10                       UNITED STATES v. WEAVER
a question of law." Sullivan, 138 F.3d at 133. Circumstances where
the citizen would feel free to go, but stays and has a dialogue with the
officer, are considered consensual, and therefore do not implicate the
Fourth Amendment. "While most citizens will respond to a police
request, the fact that people do so, and do so without being told they
are free not to respond, hardly eliminates the consensual nature of the
response." Delgado, 466 U.S. at 216. In applying the totality of the
circumstances test, courts look to numerous factors including the
time, place and purpose of the encounter, the words used by the offi-
cer, the officer’s tone of voice and general demeanor, the officer’s
statements to others present during the encounter, the threatening
presence of several officers, the potential display of a weapon by an
officer, and the physical touching by the police of the citizen. See
Bostick, 501 U.S. at 437; Michigan v. Chesternut, 486 U.S. 567, 571-
76 (1988); United States v. Mendenhall, 446 U.S. 544, 554 (1980).
Most important, for our present purposes, numerous courts have noted
that the retention of a citizen’s identification or other personal prop-
erty or effects is highly material under the totality of the circum-
stances analysis. See Royer, 460 U.S. at 501; 4 Wayne R. LaFave,
Search & Seizure § 9.3(a), at 103 n.74, (3d. ed. 1996) (collecting cases).4
  4
     In Royer, writing for the plurality, Justice White noted:
      Asking for and examining Royer’s ticket and his driver’s license
      were no doubt permissible in themselves, but when the officers
      identified themselves as narcotics agents, told Royer that he was
      suspected of transporting narcotics, and asked him to accompany
      them to the police room, while retaining his ticket and driver’s
      license and without indicating in any way that he was free to
      depart, Royer was effectively seized for the purposes of the
      Fourth Amendment.
460 U.S. at 501 (emphasis added). Weaver argues that this language
from Royer supports the categorical approach he advances. This is sim-
ply not true. Not only have more recent cases limited the effect of this
language from Royer, see Bostick, 501 U.S. at 437 (emphasizing that
"seizure" inquiry is based on a totality of the circumstances and that no
one factor is dispositive), but the passenger in Royer was on his way to
board an airplane and without his ticket he could not do so. This fact is
critical in our determination, as will soon become apparent. Had Officer
Leeds retained Weaver’s bus ticket as he was about to board a bus, the
result in this case might be different. But those facts are not before us,
and we intimate no view on that issue.
                        UNITED STATES v. WEAVER                           11
Weaver, however, argues that this last factor should be dispositive
under the totality of the circumstances analysis. We disagree.

   Despite Weaver’s suggestion, we expressly refuse to adopt a
bright-line rule that when an officer retains an individual’s identifica-
tion beyond its intended purpose, in this case checking for outstand-
ing warrants, the individual whose identification is retained is
effectively seized for purposes of the Fourth Amendment. Time and
again, the Supreme Court has noted that the inquiry into whether a
police-citizen encounter is a "seizure" for purposes of the Fourth
Amendment is determined by examining the totality of the circum-
stances, and no one factor is dispositive. See Bostick, 501 U.S. at 437;
Chesternut, 486 U.S. at 571-76; Mendenhall, 446 U.S. at 554. When
viewed objectively, the encounter between Weaver and Officer Leeds
does not amount to a constitutionally prohibited "seizure." Our deci-
sions in Sullivan, Lattimore, and United States v. Rusher, 966 F.2d
868 (4th Cir. 1992), support our conclusion.

   In Lattimore, the en banc court found that under the totality of the
circumstances no Fourth Amendment violation occurred in the con-
text of a traffic stop. After issuing the defendant two citations and
returning the defendant’s driver’s license, the officer asked the defen-
dant whether there was any contraband in his car. The defendant
responded in the negative, and then consented to the officer’s request
to search his car. That search uncovered contraband. The court held
that under the totality of the circumstances the encounter was consen-
sual. In reaching that conclusion, the court stressed the fact that the
officer did not question the defendant "until after the officer had
issued the citations and returned [the defendant’s] driver’s license."
Lattimore, 87 F.3d at 653. In Rusher, we failed to find a Fourth
Amendment violation where, following a routine traffic stop, a police
officer asked the defendant if he had any illegal contraband. Once
again, as in Lattimore, the officer returned the defendant’s driver’s
license and told him that he was "free to go." Rusher, 966 F.2d at 872.5
After doing this, the officer then asked the defendant if there was any-
  5
   It should be noted that in a similar, albeit distinguishable, context, the
Fourth Amendment does not require that a lawfully seized defendant be
advised that he is "free to go" before his consent to search will be recog-
nized as voluntary. Ohio v. Robinette, 519 U.S. 33, 39-40 (1996).
12                      UNITED STATES v. WEAVER
thing illegal in his car. After the defendant stated that no contraband
was present, he consented to a search, which uncovered illegal drugs.
Under those circumstances, the court found the officer’s questions to
be within the confines of the Fourth Amendment because the encoun-
ter between the defendant and the officer was consensual. Id. at 877.
Finally, in Sullivan, we held that no Fourth Amendment violation
occurred because the officer "did not question [the defendant] until
after he had returned [his] license and registration, thus ending the
traffic stop and affording [the defendant] the right to depart." 138
F.3d at 133.

   To be sure, one common thread in Sullivan, Lattimore, and Rusher
is that the searches occurred after the respective defendants had got-
ten their identification back. Thus, it is only logical to draw from
these cases, as well as Royer, that the retention of a person’s identifi-
cation is an important factor in determining whether a "seizure"
within the meaning of the Fourth Amendment occurred. While this
fact may be important, under the totality of the circumstances, it
surely is not dispositive. Rather, placing those cases in their proper
context shows that there is a uniqueness to those cases that is lacking
in the case before us.

   Sullivan, Lattimore, and Rusher all occurred within the context of
a routine traffic stop. In those situations, the retention of one’s driv-
er’s license would have effectively seized the individual because it is
illegal to drive without a license in one’s possession. In the context
of a traffic stop, if an officer retains one’s driver’s license, the citizen
would have to choose between the Scylla of consent to the encounter
or the Charybdis of driving away and risk being cited for driving
without a license. That is, of course, no choice at all, and that is why,
in those cases, the retention of one’s license is a highly persuasive
factor in determining whether a seizure occurred. See, e.g., United
States v. Mendez, 118 F.3d 1426, 1430 (10th Cir. 1997) (noting
bright-line rule in the traffic stop context); United States v. Chan-
Jimenez, 125 F.3d 1324, 1326 (9th Cir. 1997) (same); United States
v. Winfrey, 915 F.2d 212, 216 (6th Cir. 1990) (same); United States
v. Jefferson, 906 F.2d 346, 349 (8th Cir. 1990) (same). In the case
before us, no such choice exists.

   Here, Weaver was a pedestrian and could have walked away from
the encounter. Admittedly, doing so may have created an awkward
                       UNITED STATES v. WEAVER                        13
situation between Weaver and Officer Leeds, but awkwardness alone
does not invoke the protections of the Fourth Amendment, particu-
larly so when the test employed is an objective one. Unlike those situ-
ations that may occur in the traffic stop context, pedestrian encounters
are much less restrictive of an individual’s movements. In the context
before us, Weaver could have refused to cooperate when Officer
Leeds asked him for his identification. Indeed, the Supreme Court has
"consistently held that a refusal to cooperate, without more, does not
furnish the minimal level of objective justification needed for a deten-
tion of seizure." Bostick, 501 U.S. at 437 (citations omitted). Thus,
had Weaver walked away from Officer Leeds, the officer would have
been forced to end the encounter. See United States v. Wilson, 953
F.2d 116, 122-23 (4th Cir. 1991) (seizure found where officer per-
sisted in questioning after passenger conveyed unwillingness to
engage in further conversation with officer). Instead, Weaver chose
to remain and acquiesced to Officer Leeds’ requests for his identifica-
tion and that he accompany him to the two banks in question. In fact,
the facts presented to us clearly show that the encounter between
Weaver and Officer Leeds cannot be described as anything but con-
sensual.

   Furthermore, the documentation in question, Weaver’s driver’s
license, was not necessary to his continuing onward like the airplane
tickets in Royer, or the driver’s licenses in Sullivan, Lattimore, and
Rusher. Weaver was traveling by bus, and therefore he could legally
go about his business without his driver’s license. See United States
v. Waksal, 709 F.2d 653, 660 (11th Cir. 1983) (noting that defendant
did not feel free to go when officers retained documents necessary for
him to continue on his journey). While it is without question that a
driver’s license is one of the most valuable pieces of personal identifi-
cation possessed by any citizen,6 it does not logically follow that any
time an officer retains someone’s driver’s license that such retention
blossoms into an unconstitutional seizure. Under the totality of the
circumstances, however, something more is required.

  As noted above, in applying the totality of the circumstances test,
we look at such factors as the time, place and purpose of the encoun-
  6
   See United States v. De La Rosa, 922 F.2d 675, 683 (11th Cir. 1991)
(Clark, J., dissenting).
14                     UNITED STATES v. WEAVER
ter, the words used by the officer, the officer’s tone of voice and gen-
eral demeanor, the presence of multiple officers, the potential display
of a weapon by an officer, and whether there was any physical contact
between the officer and the defendant. In the case before us, the
record shows that although Officer Leeds was in uniform and armed,
he at no point threatened Weaver or brandished his weapon, the
encounter occurred in a public parking lot in the middle of the day,
Officers Jones and Nicolo did not come onto the scene until after
Weaver had agreed to accompany Officer Leeds to the bank in ques-
tion, and the record is void of any indication that Weaver was any-
thing but agreeable to Officer Leeds’ request that he accompany him
to the bank. Finally, Officer Leeds stood outside his squad car, next
to Weaver, when he asked whether Weaver would accompany him to
another bank and at no point was Weaver’s license held in the police
cruiser after the necessary check was completed. See United States v.
Analla, 975 F.2d 119, 124 (4th Cir. 1992) (fact that license was not
taken into squad car important in determining consensual nature of
encounter). In light of these facts, Weaver was free at this point to
request that his license be returned to him so that he could end the
encounter. Id. For whatever reason, Weaver chose not to do this.
Instead, Weaver chose to stay and have a dialogue with Officer Leeds
and accompany him to the two banks in question. Under the totality
of the circumstances, we are convinced that the encounter between
Weaver and Officer Leeds was consensual and therefore does not
implicate the Fourth Amendment.

   To the extent that any of our sister circuits have adopted per se
rules in this context, we respectfully decline to follow their example.
In United States v. Jordan, a case on which Weaver heavily relies, the
District of Columbia Circuit recognized that under the totality of the
circumstances test "only in rare instances will any one factor produce
an inexorable conclusion that a seizure has occurred." 958 F.2d 1085,
1086 (D.C. Cir. 1992). One such circumstance is the retention of
one’s driver’s license. In Jordan, the court held that "‘once the identi-
fication is handed over to police and they have had a reasonable
opportunity to review it, if the identification is not returned to the
detainee [it is] difficult to imagine that any reasonable person would
feel free to leave without it.’" Id. at 1087 (quoting United States v.
Battista, 876 F.2d 201, 205 (D.C. Cir. 1989)); see, e.g., United States
v. Cordell, 723 F.2d 1283, 1285 (7th Cir. 1983); United States v.
                       UNITED STATES v. WEAVER                        15
Thompson, 712 F.2d 1356, 1359 (11th Cir. 1983). In the immigration
context, the Fifth Circuit found that the retention of one’s alien regis-
tration card "significantly impaired" an individual’s right to "consent"
to a search. United States v. Chavez-Villarreal, 3 F.3d 124, 128 (5th
Cir. 1993). In fact, the court noted that the officer’s "retention of the
green cards reinforced his authority" and therefore made actual con-
sent improbable. Id. These approaches, we believe, are contrary to the
Supreme Court’s teachings in Bostick because they elevate one factor
above all others in determining whether a seizure has occurred, and
therefore we decline Weaver’s invitation to follow them.

   Because we hold that the encounter between Weaver and Officer
Leeds was consensual, and therefore did not constitute a "seizure"
within the meaning of the Fourth Amendment, it necessarily follows
that any evidence that flowed from this encounter was not illegally
obtained. Accordingly, we affirm the district court’s denial of Wea-
ver’s motion to suppress.

                                  IV.

   Federal Rule of Evidence 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 . . . [to show] identity." Fed. R. Evid. 404(b). Generally
speaking, Rule 404(b) is a rule of inclusion. Accordingly, "other
crimes" evidence will be admissible if it is relevant to some other
issue besides character, it is both necessary and reliable, and its pro-
bative value outweighs its prejudicial effect pursuant to Rule 403.
United States v. Queen, 132 F.3d 991, 997 (4th Cir. 1997). Under the
plain language of Rule 404(b), "other crimes" evidence may be used
to show identity. We review the admission of evidence for an abuse
of discretion. United States v. Haney, 914 F.2d 602, 607 (4th Cir.
1990). A district court will not be found to have abused its discretion
unless its decision to admit evidence under Rule 404(b) was arbitrary
and irrational. Id.

  To properly answer the question before us, we need not discuss the
merits of Weaver’s claims because the admission of the evidence was
harmless. Evidentiary rulings are subject to review for harmless error.
See Fed. R. Crim. P. 52(a). Such rulings will be found harmless if we
16                     UNITED STATES v. WEAVER
are able to conclude, "‘with fair assurance, after pondering all that
happened without stripping the erroneous action from the whole, that
the judgment was not substantially swayed by the error.’" United
States v. Brooks, 111 F.3d 365, 371 (4th Cir. 1997) (quoting United
States v. Heater, 63 F.3d 311, 325 (4th Cir. 1995)). Here, as the gov-
ernment correctly points out, the evidence was harmless in light of the
overwhelming evidence against the defendant.

   In the case before us, five witnesses independently identified Wea-
ver in a photo array and again in court, while two others identified
him only in court. In total, seven witnesses identified Weaver as the
robber. Furthermore, there were numerous photographs taken from
video images showing Weaver, which corroborated witness accounts
of the robberies. Because there was more than enough evidence to
prove identity even without the evidence in question, its admission
was harmless. Additionally, the introduction of the evidence was
harmless because "it is clear beyond a reasonable doubt that the jury
would have returned a verdict of guilty absent this testimony." United
States v. McMillon, 14 F.3d 948, 955 (4th Cir. 1994) (citing United
States v. Hasting, 461 U.S. 499 (1983)). In accordance with McMil-
lon, which held inadmissable Rule 404(b) evidence to be harmless,
we hold that the admission of the evidence pertaining to the June 10
robbery was harmless, and therefore the jury’s verdict should not be
disturbed.

                                   V.

   Finally, this court reviews a party’s allegation that the district
court’s behavior deprived that party of his or her due process right to
a fair trial for an abuse of discretion. United States v. Castner, 50 F.3d
1267, 1272 (4th Cir. 1995). To be sure, district courts have a duty to
conduct a jury trial in an impartial manner. Id. District courts have a
duty to avoid creating even the slightest appearance of partiality and
must refrain from repeated intervention on the side of one of the par-
ties. Id. They are also charged with exercising reasonable control over
the presentation of the evidence, so as to ensure that the truth may be
effectively determined. Id. In doing so, a district court must take great
pains to avoid the appearance that it is usurping "the role of either the
prosecutor or the defendant’s counsel." United States v. Parodi, 703
F.2d 768, 776 (4th Cir. 1983). Should the district court be unable to
                          UNITED STATES v. WEAVER                            17
comply with these requirements, a new trial is required. Id. (citing
United States v. Robinson, 635 F.2d 981, 984 (2d Cir. 1980)).
   Weaver argues that his Count Three conviction was obtained in
derogation of his due process rights because of the "district court’s
uninvited rescue of the Government’s fatally defective proof" relating
to that count. The record, however, does not support this proposition.
As the government correctly points out, the district court did not tell
the government how to prove its case, nor did it act as an advocate
on behalf of the government. All the court did was fulfill its duty
under the Rules of Evidence. Its actions surely did not exhibit "such
a high degree of favoritism or antagonism as to make fair judgment
impossible." Liteky v. United States, 510 U.S. 540, 555 (1994) (in the
context of a recusal motion). All the court did was to inform the gov-
ernment that it needed to provide a verifying document on the issue
of insurability and then extend them the time necessary to obtain such
documentation.7 In fact, the court, when asked, purposefully avoided
commenting on what type of evidence would be sufficient: "I don’t
think I can answer your question directly . . . which is what do I think
will be sufficient evidence? I mean I am not going to try your case
for you." Therefore, we conclude that the district court did not abuse
its discretion when it told the government that it needed to provide a
certificate of insurability in order to show proof of insurability and
then provide the government with the necessary amount of time to do
so.
                                      VI.
  For the foregoing reasons, we affirmed the district court’s order
denying Weaver’s motion to suppress, and also affirm the district
court’s evidentiary rulings.
                                                                AFFIRMED
  7
   Also undercutting Weaver’s claim is the court’s express statement of
neutrality:
      And you need the certificate of insurability if it is at issue. As
      I say, it usually is stipulated. I’ve never seen this happen [i.e.,
      not being stipulated to]. I would do, on this kind of technical
      issue, I would do the same for the defendant. This is not a matter
      of the absence of preparation or anything like that as far as trying
      to drum up testimony.
