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             DISTRICT OF COLUMBIA COURT OF APPEALS

                                  No. 10-FS-709

                             IN RE L.C., APPELLANT.

                         Appeal from the Superior Court
                          of the District of Columbia,
                                 (DEL 3131-09)

                      (Hon. Hiram Puig-Lugo, Trial Judge)

(Argued November 9, 2012                                    Decided June 5, 2014)

      Stefanie Schneider, Public Defender Service, with whom James Klein and
Alice Wang, Public Defender Service, were on the brief, for appellant.

      John J. Woykovsky, Assistant Attorney General, with whom Irvin B. Nathan,
Attorney General for the District of Columbia, Todd S. Kim, Solicitor General, and
Rosalyn Calbert Groce, Deputy Solicitor General, were on the brief, for appellee.

     Before WASHINGTON, Chief Judge, GLICKMAN, Associate Judge, and
NEBEKER, Senior Judge.

      Opinion for the court by Associate Judge GLICKMAN.

      Dissenting opinion by Senior Judge NEBEKER at page 21.


      GLICKMAN, Associate Judge:        This is an appeal from a delinquency

adjudication after a bench trial on charges arising out of an attempted carjacking.

The case against L.C. rested on the complainant‟s identifications of him shortly
                                           2

after the crime occurred and a month later at trial. L.C. claims the trial court erred

in precluding him from presenting expert testimony on relevant psychological

factors bearing on the reliability of such eyewitness identifications. We agree that

the court erred in ruling that the proffered testimony was not “beyond the ken” of

the average layperson without conducting the particularized inquiry required by

our decisions in Dyas v. United States1 and Benn v. United States (Benn II).2 We

cannot dismiss the error as harmless. We therefore vacate the judgment and

remand the case for further proceedings to determine the admissibility of the

expert‟s testimony.



                                           I.



      According to the government‟s evidence, the complainant, Adrienne Kinney,

had just parked her car in the alley behind her home in the 300 block of Division

Avenue, N.E., on the evening of November 22, 2009, when she and her mother

(who was accompanying her) were accosted by two unknown men. One of the

men pushed Ms. Kinney back into her car, yelled at her, and tried to wrest her car

keys from her hands. She resisted, and as the women began screaming for help



      1
          376 A.2d 827, 832 (D.C. 1977).
                                         3

and honking the car horn, the two assailants gave up and fled without taking

anything. Ms. Kinney and her mother immediately called the police, who arrived

within two or three minutes. Ms. Kinney told police the man who grabbed for her

keys was taller than she was, of medium build and complexion, and that he was

wearing an open-faced ski mask and a light blue ski jacket with a white stripe or

stripes. She said his companion also wore a mask and was dressed in black.3



      Within a few minutes, the police stopped appellant and a second man on the

street at a location approximately 200 feet from the scene of the attempted

carjacking, in the area toward which the perpetrators had run. Appellant was

wearing a light blue jacket with white stripes; in his pocket police later found an

open-faced ski mask. The man accompanying him had on a black jacket and blue

jeans; the police did not find a mask in his possession. The police arranged for Ms.

Kinney to view the two men. Sitting in a police car at a distance of approximately

fifty feet, she identified appellant as her attacker and his companion as the second



(continued…)
      2
        978 A.2d 1257, 1269-70, 1273-74 (D.C. 2009).
      3
         Although Ms. Kinney‟s mother also talked to the police and participated in
the ensuing show-up identification procedure, she did not testify and neither party
relied on her at trial. We therefore omit any further description of her involvement
and the information she gave the police.
                                         4

would-be carjacker. Ms. Kinney stated that she recognized appellant‟s jacket, his

complexion, his build, and his face, and she commented, “That‟s why his hair . . .

looked puffy in the ski mask—he has dreads.”



      Four weeks later, at appellant‟s trial, Ms. Kinney made an in-court

identification of appellant.   She testified that she first noticed him and his

companion when she drove her car into the alley, and that she paid close attention

to them because they made her nervous. The two men were strangers whom she

had never seen before that night. As she got out of her car and proceeded to gather

her things, she was hoping they would walk on by, which they did—but then they

abruptly turned and “started to rush” her. Ms. Kinney claimed she had a good look

at appellant‟s clothing; motion lights on the building behind her enabled her to see

the colors of his jacket. She was face to face with appellant as they struggled over

her keys. Although he was wearing a ski mask, it had a wide opening, through

which Ms. Kinney said she could see the shape of his face and his nose, lips, eyes,

teeth and skin.   She professed to be certain of her identification. On cross-

examination, though, Ms. Kinney agreed that she would describe appellant as

having a dark complexion rather than a medium complexion.                 She also

acknowledged that during the assault, she was screaming, her heart was racing, and

she was afraid for both herself and her mother.
                                          5

      Appellant‟s defense at trial was misidentification.           He called two

witnesses—his older cousin, with whom he and his mother resided, and William

Locust, the person whom the police had stopped with L.C.          They testified that

L.C. was on the front steps of his neighbor‟s house at the time of the attempted

carjacking, and that he had just left there and was walking to a nearby convenience

store and a gas station when the police stopped him.



      To bolster his misidentification defense, appellant sought to call Dr. Steven

Penrod to testify as an expert about research findings regarding psychological

factors arguably present in this case that had been shown to reduce the probativity

of eyewitness identifications. The pertinent proffered factors included: an effect

known as “clothing bias” that can result in a mistaken identification when the

eyewitness is shown a suspect who is wearing clothing similar to that the witness

had described;4 the poor correlation between the confidence an eyewitness



      4
         For example, Dr. Penrod apparently was prepared to testify about a recent
study in which subjects viewed a target individual wearing distinctive clothing.
When, later in the day, the subjects were shown another person wearing similar
clothing, half of the subjects incorrectly identified the person as the target. See
also State v. Henderson, 27 A.3d 872, 903 (N.J. 2011) (en banc) (noting research
findings indicating that “showups increase the risk that witnesses will base
identifications more on similar distinctive clothing than on similar facial features”)
(citing Jennifer E. Dysart et al., Show-ups: The Critical Issue of Clothing Bias, 20
Applied Cognitive Psychol. 1009, 1019 (2006), and A. Daniel Yarmey et al.,
                                                                       (continued…)
                                         6

expresses and the accuracy of the identification; studies showing that stress and

emotional arousal negatively affect the accuracy of identifications by impairing the

witness‟s ability to perceive and to remember the perpetrator‟s face;5 and the

heightened suggestivity and unreliability of show-up identifications as compared to

other identification procedures. The government moved in limine to exclude Dr.

Penrod‟s anticipated testimony on the grounds that it did not satisfy the first or

third prongs of the three-prong test for the admission of expert testimony set forth

in Dyas.6 Specifically, the government argued, the proffered testimony was not

“beyond the ken of the average layman,” and the unsettled state of scientific

knowledge did not permit a reasonable opinion to be offered by any expert. The


(continued…)
Accuracy of Eyewitness Identifications in Showups and Lineups, 20 Law & Hum.
Behav. 459, 461, 470 (1996)).
      5
          Among other things, Dr. Penrod was prepared to testify about a “meta
analysis” he had performed of some twenty-seven independent tests on the effect
of stress on the reliability of eyewitness identifications. He found that the average
error rate in the identifications was 34% when the witness was under high stress as
compared with 19% under low stress conditions.
      6
         We held in Dyas that expert testimony must satisfy three criteria to be
admissible: (1) the subject matter of the testimony must be so distinctively related
to some science, profession, business or occupation as to be beyond the ken of the
average layperson; (2) the witness must have sufficient skill, knowledge or
experience in the field or calling as to make it appear that his opinion or inference
will probably aid the trier of fact in its search for truth; and (3) the state of the
pertinent art or scientific knowledge must permit a reasonable opinion to be
asserted by an expert. Dyas, 376 A.2d at 832.
                                         7

motion asserted that this court‟s case law supported the exclusion of expert

testimony on the psychological factors affecting the reliability of eyewitness

identification.7



      After hearing argument on the motion at a pretrial hearing, but without either

conducting a voir dire examination of Dr. Penrod (who was present and available

for that purpose) or, so far as appears, evaluating the proffered psychological

research on which Dr. Penrod relied, the trial court ruled his testimony

inadmissible on the sole ground that none of it was beyond the ken of the average

layperson. Rather, in the court‟s view, the proposed areas of expert testimony

were all matters within the reach of “common sense” that the defense could bring

out in cross-examination and address in argument. The court did not rule on

whether the other requirements of Dyas were satisfied.



      In closing arguments, opposing counsel disputed whether the reliability of

Ms. Kinney‟s identification of appellant was undermined by clothing bias, stress,

and the suggestiveness of the show-up procedure, whether there were significant



      7
        The government did not mention this court‟s opinion in Benn II, which
had been decided three months earlier. Appellant cited Benn II to the trial court
when the motion was argued.
                                          8

inconsistencies in her previous descriptions of her assailant, and whether her

confidence in her identification was entitled to weight.        The court‟s ruling

excluding Dr. Penrod‟s testimony precluded appellant‟s counsel from supporting

his arguments on these matters with scientific studies.8



      After hearing arguments, the trial court credited Ms. Kinney‟s identification

of appellant and found him guilty of carjacking and assault with intent to commit

robbery.



                                         II.



      As L.C. argues, and as the government does not dispute, our decisions in

Benn II and Russell v. United States9 now make it clear that the trial court erred in

summarily concluding that the proffered expert testimony was not beyond the ken

of the average layperson. In those cases this court recognized that the insights of

modern      psychological   research   into the factors    influencing   eyewitness

identifications are not matters of common knowledge or common sense and are,

      8
       The court sustained an objection when defense counsel attempted to cite
Dr. Penrod‟s research, on the ground that the research was “not common
knowledge.” [12/31/09 Tr. at 105-06]
      9
           17 A.3d 581 (D.C. 2011).
                                          9

indeed, often counterintuitive.10 It makes no difference that the fact-finder in this

case was an experienced trial judge whose background and knowledge in the area

might exceed that of the average layperson. This court has rejected the argument

that when the Dyas issue is presented in a bench trial, the proper standard for

admissibility should be the “ken of the presiding trial judge” rather than that of the

average layperson.11 The average layperson standard applies “even though it could

be said that the trial [judge is] competent to resolve the issue without the aid of an

expert.”12




      10
           See Benn II, 978 A.2d at 1277 (“Despite the fact that jurors may be
familiar from their own experience with factors relevant to the reliability of
eyewitness observation and identification, it cannot be said that psychological
studies regarding the accuracy of an identification are within the ken of the typical
juror.”) (internal quotation marks, brackets and ellipses omitted); id. at 1268
(noting that “jurors, as a matter of common sense, are not fully aware of the factors
that influence eyewitness testimony,” and that research has disproved commonly
held beliefs in the accuracy of eyewitness identifications); see also Russell, 17
A.3d at 588 (stating that the court will have to undertake a “more in-depth
consideration” of the proffered testimony on remand before rejecting it “based
upon previously accepted common sense notions of what matters are within the
ken of the average lay person”).
      11
             Girardot v. United States, 996 A.2d 341, 347 (D.C. 2010) (brackets
omitted).
      12
            Id. at 348.
                                         10

      Seeking to avoid the remedy required by Russell and Benn II—a remand for

a full Dyas inquiry that likely would include a voir dire examination of Dr.

Penrod13—the government urges us to affirm on an alternative ground: There was

no reversible error, the government contends, because the exclusion of Dr.

Penrod‟s testimony “was justified by the corroborative evidence in this case, which

demonstrated the reliability of Ms. Kinney‟s identification of appellant.”14     We

must reject this argument.



      First, even if we were to assume arguendo that, in deciding whether to admit

Dr. Penrod‟s testimony, the trial court had discretion to consider the evidence

corroborating the complainant‟s identification of appellant, the court did not

exclude the expert testimony on that basis, and the court certainly was not

obligated to do so. That suffices to foreclose the government‟s argument, because




      13
           See Russell, 17 A.3d at 588; Benn II, 978 A.2d at 1277-80.
      14
          Brief for Appellee at 29. There was, of course, both evidence
corroborating Ms. Kinney‟s identification of appellant (e.g., the jacket he was
wearing and the ski mask in his pocket when he was stopped) and evidence
contradicting that identification (e.g., the testimony of appellant‟s witnesses). The
government‟s argument discounts the worth of the latter evidence.
                                           11

this court may not affirm a discretionary ruling on a ground the trial court did not

rely on and had discretion to reject.15



      Second, and more fundamentally, the corroborative evidence was irrelevant

to the question of the admissibility of appellant‟s proffered expert testimony, for

the answer to that question depended only on whether the expert testimony would

satisfy the three Dyas criteria and, if so, whether any danger of unfair prejudice or

the like would nonetheless mandate its exclusion.16 Even in a bench trial, the

inquiry as to admissibility does not call for the court to assess the weight of

pertinent and admissible expert testimony in light of the anticipated strength of the

opposing party‟s evidence.



        In general, if evidence is relevant, it should be admitted unless it is barred

by some other legal rule.17 “There are two components to relevant evidence:


      15
           See Randolph v. United States, 882 A.2d 210, 219 (D.C. 2005).
      16
          See Ibn-Tamas v. United States, 407 A.2d 626, 632 (D.C. 1979); accord
Robinson v. United States, 50 A.3d 508, 523 (D.C. 2012) (“In general, expert
testimony should be admitted if it is relevant and is likely to help the trier of fact in
its search for the truth, that is to say, in understanding the evidence, determining
the facts that must be found and rendering its verdict.”) (internal citations and
quotation marks omitted).
      17
          See, e.g., Reavis v. United States, 395 A.2d 75, 78 (D.C. 1978)
(“Relevance, and the concepts it embodies, determines initially whether a proffered
                                                                     (continued…)
                                         12

materiality and probative value.”18 “[T]he fact sought to be established by the

evidence must be material, which is to say that the party must establish that fact as

a condition to prevailing on the merits of his case.”19 And the evidence must have

probative value, meaning “the tendency of evidence to establish the proposition

that it is offered to prove.”20      The probativity threshold for purposes of

admissibility is low: An item of evidence, to be relevant, need only “tend[] to

make the existence or nonexistence of a fact more or less probable than would be

the case without that evidence.”21 As Professor McCormick explains:



(continued…)
item of evidence will be admissible.”); 2 Clifford S. Fishman, JONES ON EVIDENCE
§ 11:1 at 258 (7th ed. 2000) (“Evidence that is relevant should be admitted, unless
barred by some other rule.”); 1 Kenneth S. Broun et al., MCCORMICK ON EVIDENCE
§ 184 at 728 (6th ed. 2006) (“[U]nless there is some such distinct ground for
refusing to hear the evidence, it should be received.”) (footnote omitted); Fed. R.
Evid. 402 (“Relevant evidence is admissible unless any of the following provides
otherwise: the United States Constitution; a federal statute; these rules; or other
rules prescribed by the Supreme Court. Evidence which is not relevant is not
admissible.”).
      18
           MCCORMICK ON EVIDENCE § 185 at 729 (footnote omitted).
      19
          Reavis, 395 A.2d at 78; see also MCCORMICK ON EVIDENCE § 185 at 729
(“[Materiality] looks to the relation between the propositions that the evidence is
offered to prove and the issues in the case.”).
      20
           Id. § 185 at 730.
      21
           Punch v. United States, 377 A.2d 1353, 1358 (D.C. 1977); accord
Plummer v. United States, 813 A.2d 182, 188 (D.C. 2002) (“Evidence is relevant if
it has „any tendency to make the existence of any fact that is of consequence to the
                                                                       (continued…)
                                         13

             An item of evidence, being but a single link in the chain
             of proof, need not prove conclusively the proposition for
             which it is offered. It need not even make that
             proposition appear more probable than not. Whether the
             entire body of one party‟s evidence is sufficient to go to
             the jury is one question. Whether a particular item of
             evidence is relevant to the case is quite another. It is
             enough if the item could reasonably show that a fact is
             slightly more probable than it would appear without that
             evidence. Even after the probative force of the evidence
             is spent, the proposition for which it is offered still can
             seem quite improbable.22



      “Ordinarily,” therefore, “any evidence [that] is logically probative of some

fact in issue is admissible[,] and if the evidence offered conduces in any reasonable

degree to establish the probability or improbability of a fact in controversy, it


(continued…)
determination of the action more probable or less probable than it would be
without the evidence.‟”) (quoting Street v. United States, 602 A.2d 141, 143 (D.C.
1992)); Fed. R. Evid. 401 (“Evidence is relevant if: (a) it has any tendency to make
a fact more or less probable than it would be without the evidence; and (b) the fact
is of consequence in determining the action.”). To put it differently, evidence is
irrelevant in the sense that it lacks probative value only if “the evidence does not
justify any reasonable inference as to the fact in question. Cases involving such
evidence are few and far between.” MCCORMICK ON EVIDENCE § 185 at 735
(emphasis in original; footnote omitted).
      22
           MCCORMICK ON EVIDENCE § 185 at 733 (footnotes omitted). See, e.g.,
Winfield v. United States, 676 A.2d 1, 4 (D.C. 1996) (en banc) (holding that when
the defendant seeks to introduce evidence of a third-party perpetrator, “there is no
requirement that the proffered evidence must prove or even raise a strong
probability that someone other than the defendant committed the offense”)
(internal quotation marks and alterations omitted).
                                           14

should go to the jury” or, in a non-jury trial, to the judge.23 Thus, evidence may

not be rejected as irrelevant merely because it is contradicted by other evidence.24



      The foregoing principles, applicable to evidence in general, apply equally to

the admission of relevant expert testimony. The standard of relevance is the same

for expert testimony as it is for other evidence; as we have held, “there is only one

standard of relevance.”25 It is true that the trial judge must exercise discretion to

decide whether proffered expert testimony is likely to assist the trier of fact in the

performance of its duties—“that is to say, in understanding the evidence,

determining the facts that must be found and rendering its verdict.” 26 But such

helpfulness is determined by the three criteria governing the admissibility of expert


      23
            Plummer, 813 A.2d at 188-89 (internal quotation marks and brackets
omitted).
      24
          Evidence that is relevant and not barred by some other legal rule may be
excluded, in the trial court‟s discretion, if the court finds that its probative value is
substantially outweighed by a danger of unfair prejudice, confusion of the issues,
or other legitimate concerns. See (William A.) Johnson v. United States, 683 A.2d
1087, 1100 (D.C. 1996) (en banc) (adopting Federal Rule of Evidence 403). The
trial court in this case did not make such a finding, nor does the government
suggest that it should or could have done so.
      25
            Winfield, 676 A.2d at 3.
      26
          Hager v. United States, 856 A.2d 1143, 1147 (D.C. 2004) (quoting Steele
v. D.C. Tiger Market, 854 A.2d 175, 181 (D.C. 2004)) (internal quotation marks
omitted), amended by 861 A.2d 601 (D.C. 2004).
                                         15

opinion testimony set forth in Dyas, and ultimately turns on “the relevance and

probative value of the proposed scientific evidence.”27 In the end, therefore, the

criterion of helpfulness is met if the expert testimony is material and if its

probative value is not substantially outweighed by the danger of unfair prejudice or

other legitimate concerns.



      Thus, the criterion of helpfulness is not a grant of authority to the trial judge

to exclude relevant and otherwise admissible expert testimony merely because it is

against the expected weight of the evidence.28 Still less does Dyas authorize the

trial judge to exclude expert testimony as unhelpful based on the perceived

strength of the opponent‟s evidence alone.29 The rationality of such a rule cannot

be defended, for as the Supreme Court explained in Holmes v. South Carolina, “by



      27
          Benn II, 978 A.2d at 1278. Perhaps it would be more precise to say that
helpfulness turns on the materiality and probative value of the proposed scientific
evidence.
      28
          See, e.g., Western Indus., Inc. v. Newcor Can., Ltd., 739 F.2d 1198, 1202
(7th Cir. 1984) (Posner, J.) (holding that trial judge erred in excluding expert
opinion testimony, because “a judge in our system does not have the right to
prevent evidence from getting to the jury merely because he does not think it
deserves to be given much weight,” and thus “he may not screen witnesses simply
to decide whether their testimony is persuasive”).
      29
          As noted previously, while there was evidence corroborating Ms.
Kinney‟s identification of appellant, there also was evidence contradicting it.
                                         16

evaluating the strength of only one party‟s evidence, no logical conclusion can be

reached regarding the strength of contrary evidence offered by the other side to

rebut or cast doubt.”30



      In taking the opposing view, the government relies on cases in which we

have said that where corroboration of a challenged identification exists, the

exclusion of proffered expert testimony on eyewitness identification generally does

not constitute an abuse of discretion.31 But that does not mean the existence of

corroboration is a legitimate reason for the trial court to exclude the expert

testimony; it only means that the exclusion likely will not be so prejudicial as to

necessitate reversal by the appellate court. Abuse of discretion is a standard of

appellate review incorporating an assessment of prejudice. A trial court exercises

its discretion erroneously when it relies on an improper factor, but “the reviewing

court must weigh the severity of the error against the importance of the

determination in the whole proceeding and the possibility for prejudice as a


      30
           547 U.S. 319, 331 (2006). Indeed, Holmes makes clear that a rule of
evidence allowing a trial judge to exclude a defendant‟s relevant and otherwise
admissible expert testimony when the prosecution‟s evidence of the defendant‟s
guilt is strong would contravene the constitutional guarantee of “a meaningful
opportunity to present a complete defense.” Id.
      31
           See Benn II, 978 A.2d at 1280, and Hager, 856 A.2d at 1149.
                                           17

result.”32 It is only when the impact of the error is so serious we must reverse that

we say the trial court “abused” its discretion.33        In some cases in which a

challenged identification was amply corroborated, the appellate court may be able

to conclude that the erroneously excluded expert testimony would not have

undermined it significantly. When that is so, the court can conclude that the error

did not affect the outcome of the trial, and hence that there was no “abuse” of

discretion.34 But to say the trial court did not abuse its discretion is not to say the

court exercised its discretion properly.



      That brings us to whether the erroneous ruling was harmless in this case.

The burden is on the government to persuade us that “the judgment was not

substantially swayed by the error”35—a standard requiring us to find it “highly

probable” that the error did not contribute to the verdict.36 We are not prepared to


      32
             (James W.) Johnson v. United States, 398 A.2d 354, 365, 367 (D.C.
1979).
      33
            Id.
      34
         See, e.g., Heath v. United States, 26 A.3d 266, 282-85 (D.C. 2011), cert.
denied, 134 S. Ct. 898 (2014).
      35
            Kotteakos v. United States, 328 U.S. 750, 765 (1946).
      36
             Heath, 26 A.3d at 275 n.18 (D.C. 2011), (internal quotation marks
omitted).
                                         18

make such a finding here. The government‟s case rested on a single, contested

eyewitness identification of a stranger, the reliability of which the excluded expert

testimony might have afforded a reasonable basis to doubt. We said in Benn that


              [i]n a case grounded on eyewitness identifications of a
              stranger, without other corroborating evidence, and in
              which the defense depends entirely upon demonstrating
              that the identifying witnesses are not as reliable as they
              believe themselves to be, to preclude the defendant from
              presenting the scientific testimony of a qualified expert
              on research that is generally accepted and not known to
              lay jurors to prove this point is not harmless under
              Kotteakos v. United States, provided that the facts
              underlying the identifications establish a sound
              foundation for applying the principles expounded by the
              expert.37



Here, to be sure, the identification was corroborated to an extent: When L.C. was

stopped only minutes after the attempted carjacking, a short distance from the

scene, he was wearing a blue jacket with a white stripe and he had a ski mask in his

pocket—both of which matched the complainant‟s description of what her

assailant was wearing.       But without denigrating this evidence, we must

acknowledge that we cannot be confident enough that it rendered the identification

of appellant free from reasonable doubt that might have been instilled had Dr.



      37
           Benn, 978 A.2d at 1283 (footnotes omitted).
                                         19

Penrod‟s testimony been permitted.      As appellant argues, his presence in the

vicinity was not unusual given that he lived in the neighborhood, his jacket was not

uncommon, and a ski mask was an appropriate item of cold weather apparel to

have in a coat pocket in November when the nights may get chilly.               The

government presented no independent corroboration of appellant‟s guilt—no

physical or scientific evidence, incriminating admissions or behavior by appellant,

or third-party testimony implicating him in the carjacking.



      Russell is instructive. In that case we held that the trial court‟s erroneous

preclusion of testimony from the defendant‟s eyewitness identification expert

required a remand for a Dyas hearing notwithstanding the presence of

corroborative evidence comparable to, if not indeed stronger than, such evidence

here.38 We deemed it significant that there was no scientific or physical evidence

linking Russell to the crime, nor any incriminating admissions.39          And we


      38
           In Russell the defendant‟s clothing and appearance when he was
apprehended shortly after the carjacking matched the victim‟s description of the
carjacker as a man with his hair in dreadlocks wearing a black North Face jacket
with a hood, blue jeans, and black boots. Moreover, his jeans were wet and
muddy, which was consistent with the fact that a police officer had seen the
perpetrator flee into the woods. And unlike in this case, in Russell there were two
eyewitness identifications, each corroborating the other. 17 A.3d at 584, 589-90.
      39
           Id. at 589.
                                          20

recognized that “the excluded expert testimony was central to [Russell‟s]

misidentification defense;” without it, we emphasized, he “had no factual

underpinnings for the scientific theories he sought to present that might cast doubt

on the eyewitness‟ testimony.”40 Much the same is true here. If the erroneous

exclusion of the defense expert‟s testimony was not harmless in Russell, it is

difficult to see how we could reach a different conclusion in this case.41



      For the foregoing reasons, we hereby vacate the judgment and remand the

case for further proceedings to determine the admissibility of the proffered expert

testimony in accordance with Benn II under the criteria set forth in Dyas.42 “If the

trial court determines . . . that the expert testimony should have been permitted, it

shall order a new trial. If the trial court adheres to its ruling that the testimony is




      40
           Id.
      41
           The government argues that appellant was able to test the reliability of
Ms. Kinney‟s identification of him through cross-examination. But “[a]ppellant‟s
proffered scientific theories could not be developed on the cross examination of lay
witnesses.” Id. As in Russell, “[w]e are not persuaded that the fact that appellant
cross-examined vigorously the eyewitness[] and argued the shortcomings of the
identification[] to the [court] to the extent that he could means that he had a
meaningful opportunity to present his misidentification defense.” Id.
      42
           See Benn II, 978 A.2d at 1278, 1280.
                                         21

inadmissible, it shall re-enter the judgment subject to appellant‟s rights to

challenge the ruling in a renewed appeal.”43



                                                           So ordered.



      NEBEKER, Senior Judge, dissenting: There are two questions presented here:

(1) whether, on these facts, the fact-finder with life experiences needs abstract help

that effectively throws cold water, i.e. “a reasonable basis to doubt,” on the

victim‟s identification of the culprit—I say no; and (2) if the majority says it does,

whether on these facts the exclusion of such testimony visited undue prejudice on

the appellant. I say it did not. In trying to see the issue presented here through the

eyes of the majority it is apparent that their premise—per se admissibility of the

proffered testimony—is where we disagree. However, there is no en banc decision

of the court removing our issue from the near universal discretion of the trial court

in matters of expert testimony.



      The remedy dictated here is a remand for a hearing. At that hearing the trial

judge is to apply the Dyas criteria along with a voir dire of the proffered expert and

either order a new trial, or reinstate the conviction and have another appeal.

      43
           Russell, 17 A.3d at 589-90.
                                          22

Remand by the majority permits adherence to the earlier exclusion of the testimony

after the Dyas and Benn inquiry and voir dire of Dr. Penrod during which he may

be tested on whether his conclusions and those of studies he relies upon remain

valid in light of the corroborating and uncontested facts discussed herein. Should

the trial judge remain of the view that the expertise is unhelpful, he is surely free to

exclude it. Further, in light of the expanded record, any error, assumed or real, in

excluding the testimony would be reviewed for harmlessness and weighed against

the same corroborating evidence we have before us now. Super. Ct. Juv. R. 52 (a).



      Russell and Benn did not articulate a per se rule that any relevant expert

testimony on identification must be admitted.         Instead, the admission of that

evidence is still entrusted to the discretion of the trial judge who applies the

circumstances of the case to the factors articulated in Dyas.          The majority‟s

opinion is founded on the premise that the trial court summarily concluded that

expert testimony was not needed, making it necessary to remand to voir dire the

proffered expert.1 That is, on these facts, the court erred in concluding that it was


      1
        Quite surprisingly, the majority also concludes that the excluded testimony
“might have afforded a reasonable basis to doubt” the victim‟s identification.
Majority Opinion at 18. Does that mean that if the fact-finder hears the expert‟s
testimony (we don‟t assume he would lie) an acquittal must follow because a
reasonable doubt exists as a matter of law? I would hope not, but the majority
opinion surely befogs the situation and invites us to consider whether a judgment
                                                                      (continued…)
                                          23

not beyond the ken of the average layperson to evaluate the victim‟s identification

of the culprit despite the indicia of reliability from closeness of the time and

location of the arrest, the ski mask and striped jacket.



      Under the circumstances of this case, the trial court‟s ruling was within its

discretion. The court properly considered the defense‟s proffer of testimony in the

in limine hearing before concluding that none of the expert testimony would shed

light on any aspect of the identification in this case beyond those that were within

common sense knowledge. Rather than a summary conclusion, this shows the trial

court‟s ruling rested on sound and in-depth consideration of what was common

sense under the unique circumstances of this case.2        The danger in what the

majority proposes is that a blanket rule requiring the admission of the testimony of




(continued…)
of acquittal is in order—as a matter of law—if the testimony is to be accepted at a
new trial.
      2
          The majority‟s reliance on Russell and Benn reads too much into the
decisions for precedential purposes. In Russell, the time between the incident and
identification was much longer (at least an hour and twenty minutes) and the
location of arrest more distant (a number of blocks), and the witness had been
drinking. 17 A.3d 581, 583-84 (D.C. 2011). In Benn, the government‟s sole
evidence was identification, there was no physical evidence—and the appellant
was apparently not arrested near the scene shortly thereafter because the
challenged photo array was held a full week after the incident. 978 A.2d 1257,
1263-64, 1264 n.12 (D.C. 2009). In these fact-bound situations there is, in my
                                                                    (continued…)
                                       24

experts will interfere with the exercise of common sense. Indeed, as Winston

Churchill wrote 113 years ago,


            Expert knowledge is limited knowledge: and the
            unlimited knowledge of the plain man who knows only
            what hurts is a safer guide than any vigorous direction of
            a specialized character. Why should we assume that all
            except doctors, engineers, etc. are drones or worse? . . .
            Is not government itself both an art and a science? To
            manage men, to explain difficult things to simple people,
            to reconcile opposite interests, to weigh the evidence of
            disputing experts, to deal with clamorous emergency of
            the hour; are not these things themselves the
            consideration and labour of a lifetime? . . . Wherefore I
            say, from the dominion of all specialists . . . good Lord
            deliver us.



Letter from Winston Churchill to H.G. Wells (Nov. 17, 1901), in Graham Farmelo,

Churchill‟s Bomb: How the United States Overtook Britain in the First Nuclear

Arms Race 18 (2013).



      I also respectfully disagree with the majority‟s assertion—not necessary for

its decision—that “the inquiry as to admissibility does not call for the court to

assess the weight of the expert testimony in light of contrary evidence.” Majority

Opinion at 11. It does when we consider “whether the testimony would assist the


(continued…)
view, little room for controlling precedent, at least in this case.     Remember,
                                                                      (continued…)
                                         25

[fact-finder], taking into account the relevance and probative value of the proposed

scientific evidence,” an examination required under Dyas. Benn v. United States,

978 A.2d 1257, 1278 (D.C. 2009). “It is quintessentially the function of the trial

judge to determine whether expert testimony is likely to be helpful” and we review

only for abuse of discretion.3     Id. at 1279, 1280.     While we do not affirm

convictions where expert testimony is excluded and the government has only

presented eyewitness testimony, where, as here, corroborative evidence exists, “the


(continued…)
precedent is to guide, not to conquer.
       3
          My colleagues find automatic abuse of discretion from their disagreement
with the reasoning of the trial judge. Doing so treats the trial judge as an
administrator who must give reasons and bases for an administrative decision, and
if one reason is erroneous the reviewing court may not substitute its judgment for
that of the administrator, but must remand for reconsideration. See, e.g., Securities
& Exch. Comm’n v. Chenery Corp., 318 U.S. 80, 87 (1943) (“The grounds upon
which an administrative order must be judged are those upon which the record
discloses that its action was based.”). Judicial review of discretionary trial court
decisions shows no such limitation. We must uphold a discretionary trial court
decision if there is a basis to do so whether no reason or an erroneous one were
given. Id. at 88 (“In confining our review to a judgment upon the validity of the
grounds upon which the Commission itself based its action, we do not disturb the
settled rule that, in reviewing the decision of a lower court, it must be affirmed if
the result is correct although the lower court relied upon a wrong ground or gave a
wrong reason.” (internal quotation marks omitted)); see also Johnson v. United
States, 398 A.2d 354, 365-66 (D.C. 1979) (“Determinations committed to the trial
court‟s discretion do not submit themselves to a highly structured review for abuse
of discretion as easily as do most administrative determinations. . . . [W]e are
prepared to countenance imperfections in the trial court‟s exercise of discretion to
enjoy more fully the advantages of making the determination discretionary. Thus,
at times we may find that the fact of error in the trial court‟s determination caused
no significant prejudice and hold, therefore, that reversal is not required.”).
                                         26

exclusion of the proffered expert testimony by the trial court generally does not

constitute an abuse of discretion.” Id. at 1280.



      Moreover, it seems, according to the majority, that if there is “physical or

scientific evidence, incriminating admission or behavior by the appellant, or third

party testimony implicating him,” that evidence would justify denial of the expert

testimony, or at least render the exclusion harmless in all cases. Majority Opinion

at 19.   Presumably, a clear video showing L.C. committing the attempted

carjacking would justify the exclusion of expert testimony. I would hold to a lesser

standard than the majority does and acknowledge that in such circumstances expert

testimony is unhelpful and need not be presented; it is not, as the majority asserts,

merely harmless error to exclude such testimony.



      Nevertheless, I would conclude that on the evidence here, any error in

excluding the testimony is harmless. The corroborating evidence in this case, as

that in Patterson v. United States, 37 A.3d 230 amended by 56 A.3d 1152 (D.C.

2012), carries far more logically persuasive weight than given it by my colleagues.

As the majority acknowledges, we must affirm so long as “the judgment was not

substantially swayed by the error.” Kotteakos v. United States, 328 U.S. 750, 765

(1946). With the evidence here pointing to L.C. it is not prejudicial error to hold
                                        27

that a reasonable fact-finder, unaided by expert testimony, was able from human

experience alone to decide beyond a reasonable doubt that L.C. attempted the

carjacking. The evidence is well within the harmless error periphery.



      We are not dealing with the ubiquitous tan trench coat, but to me a far more

persuasive striped jacket and a ski mask,4 which my colleagues discount because it

was November. With official weather records indicating that the low temperature

on November 22, 2009, was 36 degrees,5 I am not prepared to devalue this fact as I

might be if the offense had been committed in January or February. In milder

weather such masks better perform the role of an attempted disguise than defense

against frostbite. The ski mask in November plus the proximity in time and place

of arrest—just around the block, no more than eight minutes later—of the two

men, each whom the victim recognized, also make this case appropriate for a

harmless holding. The majority admits that the ski mask and jacket match the




      4
          Much different than the generic clothing in Russell. See 17 A.3d at 584
(relating description of assailants as “two black males, both wearing black North
Face jackets with hoods, blue or dark-colored jeans, and black boots”).
      5
        National Oceanic & Atmospheric Administration records indicate that the
high for November 22, 2009 was 58 degrees and the low was 36 degrees at the
National Arboretum, the closest weather station to where the events occurred.
                                         28

victim‟s description. What more is needed? The dimensions of the stripes; the size

of the jacket; zipper or buttons!



      The majority‟s insistence that corroborating evidence measure up to some

exacting standard lacks common sense. I add to Churchill‟s observation, supra,

that while we may sometimes bind ourselves by modern thought, common sense is

today as it was in the past. Isn‟t the ski mask on a cool—not freezing—November

day without others around minutes after the flight enough? Or, are these facts to be

considered only in isolation from each other? I suggest that the conglomerate of the

facts provides enough so that a fact-finder needs no further help in assessing the

victim‟s identification testimony. To be sure, the subject of the proffered expert

testimony here would be beyond the ken of the average person, but the question is

whether, in these fact-bound circumstances, a fact-finder needs expert opinion to

evaluate the accuracy of the victim identification.



      To this, I add one other factor: a pretrial motion to suppress was filed and

denied. The issues raised (probable cause to arrest and undue suggestivity) are not

presented on appeal. Therefore, we may take as conceded that it was more likely

than not—i.e., probable cause—that L.C. attempted the carjacking, that the

identification was not unduly suggestive, and that it was reliable; there was no
                                            29

probability of an irreparable misidentification. See Turner v. United States, 622

A.2d 667, 672, 672 n.4 (D.C. 1993) (“While a show-up may not be an ideal setting

for an identification, it is not sufficient alone to establish a due process violation. . .

. Indeed, identifications conducted soon after the crime enhance the accuracy of

witnesses‟ identifications and allow innocent suspects to be quickly freed.”).



       This is important because in determining that the identification was reliable,

the trial court considered, inter alia, the stress under which the victim may have

been acting, that clothing may affect identification, and that “a person‟s perception

and recollection may be tainted by subsequent events”—the same factors L.C.

proffered were relevant for expert testimony. This is not the type of case where we

could only speculate about the thought processes of a jury. Instead, in this case the

trial judge, acting as fact-finder, made specific findings on the record which we can

look to in determining whether the exclusion of expert testimony would have

“substantially swayed” the final judgment.6 Not only did the court consider the


       6
          The majority‟s insistence on treating harmlessness equally between jury
and bench trials defies logic. There are unchallengeable differences between a jury
that deliberates and votes in secret and a judge who makes his findings known on
the record. The evaluation of the harmlessness of error in a bench trial, unlike a
jury trial, benefits from those specific findings. Where, as here, findings were
made on the record, we must acknowledge and incorporate them in determining
whether any alleged error substantially swayed those findings and the judge‟s
ultimate conclusions.
                                          30

same factors proffered by L.C., but it found they were outweighed by other

corroborating circumstances of the identification:          the proximity in space

(“basically . . . around the block”) and time (the men were stopped between 6 and 8

minutes after the attempted carjacking); that there was “nobody else in the area”;

that the clothing of both men matched the descriptions earlier given; that the ski

mask found on L.C. matched the victim‟s description (at 8:30 on a November night

with a low of 36 degrees); that the victim saw her assailant with light “shining

directly” on him; that she “looked him up and down”; that even with the ski mask

on, she could “still see his face, the shape of his face” and that the “puffy” look of

the mask was caused by L.C.‟s dread locks; and that the victim made her

identification independently from that of her mother.



      The majority holds that this “corroborative evidence [is] irrelevant to the

question of the admissibility of appellant‟s proffered testimony, [which depends]

only on whether that testimony would satisfy the three Dyas criteria . . . .”

Majority Opinion at 11 (emphasis added). I submit that life experiences and the

facts in the case so coalesce as to justify the conclusion that the fact-finder does not

need (or a jury would be confused by) this kind of expert testimony. Nothing more

is logically required and the court need not determine whether all three Dyas
                                          31

factors are met.7 Here, I find the corroborating evidence, when not given the

crabbed view of the majority, to be controlling.



      The majority says: “The case against L.C. rested on the complainant‟s

identification of him . . . .” Majority Opinion at 1. It did not. Despite their

treatment of the other identifying facts as irrelevant to the issue presented, those

facts independently vouch for the accuracy of the victim‟s observations of L.C.

during and after the attempted carjacking. If the victim‟s observations of L.C.

stood alone, or uncorroborated, the proffered expertise would assist in evaluating

their accuracy. However, when L.C. was found minutes later, on the path pointed

out by the victim, with a ski mask on a Fall night, wearing a distinctive white-

striped jacket, and no other people were around, a discretionary decision to exclude

that expertise as not helpful to the trial judge must be sustained.



      I would affirm. See Patterson, supra, 37 A.3d 230, 236-40.




      7
         The authorities purportedly backing up a conjunctive application of the
tests make no sense. Examples such as DNA evidence or a video picture of the
defendant committing the offense make any Dyas criteria other than “ken of the
average person” irrelevant to the question of admissibility. If a conjunctive
reading leads to absurd results the disjunctive becomes necessary.
