Case Title: Bomas v. State

Citation: 412 Md. 392

Docket Number: 125/08

State: maryland

Court: Maryland Supreme Court

Date: 2010-01-15T00:00:00Z

Document:
HEADNOTE:
Tavon Bomas a/k/a Tavon Bomar v. State of Maryland, No. 125, September Term, 2008
EVIDENCE - EXPERT TESTIMONY- EYEWITNESS IDENTIFICATION.  In
exercising discretion whether to admit expert testimony by a licensed psychologist in the
field of neuropsychology regarding factors that affect the reliability of eyewitness testimony,
trial courts should determine whether “the testimony will assist the trier of fact to understand
the evidence or to determine a fact in issue.”  Md Rule 5-702. Scientific advances since our
decision in Bloodsworth v. State, 307 Md. 164 (1986) have revealed a greater understanding
of the mechanics of memory that may not be intuitive to a layperson, and trial courts should
recognize these scientific advances in exercising their discretion whether to admit such
expert testimony in a particular case.  Nevertheless, the substantive standard for admissibility
set forth in Bloodsworth was not wrong, and is consonant with the current majority view.
We decline to adopt the “presumptively admissible” standard for expert testimony on the
mechanics of eyewitness identification that is advocated by Petitioner.  The Circuit Court in
this case correctly applied the “appreciable help to the trier of fact” test in excluding
Petitioner’s expert testimony.
In the Circuit Court for Baltimore City
Case No.  
104363022 - 024 
104363025
IN THE COURT OF APPEALS
OF MARYLAND
No. 125
September Term, 2008
TAVON BOMAS
A/K/A TAVON BOMAR
v.
STATE OF MARYLAND
Bell, C.J.
Harrell
Battaglia
Greene
Murphy
Adkins
Eldridge, John C., 
(Retired, Specially Assigned),
JJ.
Opinion by Adkins, J.
Filed:   January 15, 2010
1Petitioner's correct surname is Bomar, though "Bomas" is a known alias.  The
Court of Special Appeals titled its opinion Bomas v. State, 181 Md. App. 204, 956 A.2d
215 (2008).
    
Petitioner, Tavon Bomas a/k/a Tavon Bomar (hereinafter "Bomar")1 was tried and
convicted in the Circuit Court for Baltimore City of second-degree murder and use of a
handgun in a crime of violence.  Bomar's conviction rested principally on the eyewitness
identification of him by an off-duty detective.  We granted his request for a writ of certiorari
to review the standard by which trial judges determine whether to admit expert testimony on
eyewitness identification and to decide if the Circuit Court exercised proper discretion in
excluding such proffered expert testimony in this case.  Although we will clarify  the
standard for the admission of expert testimony on eyewitness identification, we shall hold
that the Circuit Court in this case properly evaluated the proffered expert testimony.
FACTS AND LEGAL PROCEEDINGS
On April 18, 2004, at approximately 2:00 a.m., off-duty detective Kenneth Bailey
stopped his truck in traffic on York Road near the Tower Lounge, a bar in Baltimore City.
Bailey heard six to eight gunshots emanating from a crowd of people that had formed on the
sidewalk roughly fifteen feet away from him.  He observed an individual, whom he later
identified as Bomar, shoot at and ultimately kill a young African American male.  After
shooting the victim, Bomar passed within a car length of Bailey's vehicle and fled the scene.
Bailey drew his weapon with the intent of pursuing Bomar but a police officer approached
Bailey and requested he identify himself.  After establishing his identity, both Bailey and the
police officer tried, unsuccessfully, to locate Bomar.  In a report Bailey filed a week later,
2
he described the shooter simply as "a black male."
The case did not progress until October 14, 2004, when police arrested Jimmy Dower
for heroin possession and he volunteered information about a shooting on York Road.
Dower told police that he had been inside Tower Lounge the night of the shooting and had
observed an argument between the shooter and the victim.  Dower originally told police that
the shooter’s name was Henry Low, but he later testified that he had known Bomar as “Henry
Low” for “[p]ractically all [of Bomar’s] life.”  According to Dower, Bomar and the victim
left Tower Lounge and he too went outside.  Dower saw Bomar retrieve a handgun from a
vacant home on York Road and fire several shots at the victim.  
After Dower identified Bomar, police constructed a photo array that included Bomar's
picture and showed the array to Bailey on October 26, 2004.  Bailey identified Bomar as the
perpetrator of the murder.  Dower met with police at a 7-11 store parking lot whereupon
police showed him the photo array.  Dower identified Bomar's picture in the array and he
signed and dated Bomar's photo.  Based upon the eyewitness identifications of Bailey and
Dower, police arrested Bomar on November 3, 2004.  Initially Bomar claimed he was not at
Tower Lounge the night of the shooting, but he later stated that he witnessed the shooting.
Bomar moved to suppress the pretrial eyewitness identifications made by Bailey and
Dower.  At the pretrial hearing and at trial, Dower repudiated his identification of Bomar as
the shooter.  He claimed a different person was the real shooter and that police had directed
him towards Bomar's photo.  Dower also expressed his reluctance to testify in court and
concern that he would incur a reputation as a "snitcher[.]"  The motions judge found the
3
photo array and Bailey's identification not impermissibly suggestive and denied Bomar's
motion to suppress.
Bomar also proffered testimony from David Schretlen, Ph.D., an expert in the field
of neuropsychology and a licensed psychologist, at a pretrial hearing.  Dr. Schretlen offered
testimony that (1) a "trained observer," such as a police officer, has no better ability to
remember faces than a lay person, (2) a witness's confidence in his testimony is not
correlated with the accuracy of his identification, (3) stress and the passage of time adversely
affect one's ability to recall events or people, (4) a police photo array can influence a
witness's identification of a suspect, and (5) juries tend to believe eyewitness testimonies in
spite of "effective cross examination."  Because Dower had recanted his identification of
Bomar at trial, Bomar sought to use Dr. Schretlen's testimony to counter Bailey's
identification.  Bomar proffered testimony on several issues from Dr. Schretlen.  On the
effect of stress on memory, Dr. Schretlen offered the following:
[Schretlen]:  Another factor that has been examined is the
level of stress that a person is under when they're trying to
encode information.  Although there are some studies showing
that moderate levels of stress are beneficial, there are a number
of studies suggesting that extremely high levels of stress actually
impede the effective encoding of to be remembered material.
* * *
Q:  Has scientific research in the area of human memory
address[ed] the area of the effect of a violent event upon human
memory?
[Schretlen]:  There's been very little data on the impact of
4
a violent event. . . . [One study uses] soldiers who are
undergoing survival skills training . . . there's a facility in which
soldiers are prepared to withstand the withers of interrogation if
they're captured as prisoners of war and in that, in that survival
skills training, they are exposed to both stressful, high stressful
and low stress interrogation techniques and [the study] has
shown that people are much better at remembering the faces of
interrogators who interrogate them in a low stress fashion
compared to interrogators who interrogate them in a high stress
fashion and there are a number of such studies showing that
when people are under high levels or exposed to high levels of
stress, their memory is actually not as good as it is when they
are under you know a sort of ordinary level, experiencing an
ordinary level of arousal[.]
* * *
I don't think people appreciate that high levels of stress
might actually impair memory rather than foster it as you gave
an example, I think, of the person who says I was so frightened,
I'll never forget that face.
* * *
Q:  Now, with regard to stress, isn't it true that the studies
seem to indicate both sides of it?  There are some studies that
say high levels of stress will indicate a lower encoding of
memories correct?
[Schretlen]:  Relatively few studies of very high levels of
stress.  The studies that I have seen of very high levels of
stress…more consistently suggest that it impedes encoding.
Studies of sort of lower levels of stress suggest that when you go
from an extremely low level to a moderate level, that can
actually be beneficial[.]
* * *
Q:  Would you agree with me doctor that someone
holding a gun on you would be a high level of stress?
[Schretlen]:  It depends on the individual.
5
* * *
[P]eople experience different levels of fear, or arousal, or
distress in response to the same event and what the studies
suggest is that people who…experience very high levels of
arousal are more likely to have problems encoding a new
memory.
* * *
Q: [W]ould you agree with me that it's generally less
stressful to witness a gun on someone else than having a gun on
you as an individual?
[Schretlen]:  I think that stands to reason.
Q: So arguably, someone who is watching . . . someone
holding a gun on someone else, would conceivably be under less
levels of stress than that person having a gun held on them
personally, correct?
[Schretlen]:  Very possibly.
Q:  And if you add to it the fact that . . . the person is a
20-year military person [who is] trained in guns and gunfire and
then also a person who is a trained law enforcement officer,
conceivably that level of stress could be even less, correct?
[Schretlen]:  It certainly is a possibility[.]
* * *
Q:  [In regard to the study of the soldiers being
interrogated under high stress and low stress situations, the
soldiers] are the focus of the stress.  The stress is happening to
them, correct?
[Schretlen]:  Yes.
Q:  Can you cite me any studies in which that particular
scenario is involved where people are watching the
6
interrogation?
[Schretlen]:  No.
With respect to the storage of information within human memory, Dr. Schretlen
offered the following:
Q:  And can you explain what the research has shown,
what the scientific research has shown in regards to human
memory and the storing of information?
[Schretlen]:  Well the major finding in that area, Your
Honor, is [that] the longer information is stored, the more it
tends to break down.  But again, what's not so intuitive about
this is that the forgetting curve is just that, a curve.  It's not a
straight line.  That is we forget the most information in the few
seconds or minutes after we're exposed to it and we forget less
and less of the material as time goes by.
* * *
Q:  And in regards to human memory…there are some
who may say that these issues are a matter of common sense.
Do you have an opinion…?
[Schretlen]:  I think some of them are a matter of
common sense but there are a number of findings that are
actually somewhat counter intuitive.
Q:  Of the ones that are counter intuitive, which ones are
they in particular?
[Schretlen]: I don't think people appreciate that the
relationship between exposure time . . . and memory encoding
accuracy . . . is a curvilinear relationship[.]
Q:  What about . . . in regards to . . . your expert
testimony that the longer information is stored in fact relates [to]
the breakdown of that information?
7
[Schretlen]:  Well, I think all – I think people would
pretty widely recognize that the more time between when you
learn something and when you're asked to remember it, the less
likely you'll remember it.  So, I'm saying I think that is actually
fairly intuitive.
In regard to the memory ability of a "trained observer," Dr. Schretlen testified as
follows:
[Schretlen]:  By and large there have been at least early
on a number of studies comparing Public Safety Officials, police
officers and other sort of lay persons in their ability to remember
faces or staged events and it doesn't appear that police officers
have any  particular advantage over a non—over lay persons.
Q:  So in your expert opinion, the research that has been
conducted it has not shown that trained observers as the police
officer is more accurate than a non-trained person?
[Schretlen]:  In general that's the case.  There are
certainly some studies showing that police officers tend to be a
little bit better at recording peripheral details but they're not
typically better at remembering faces.
The motions judge declined to allow this testimony because she felt it would be
unhelpful to a jury and that a jury was capable of appropriately evaluating and weighing the
eyewitness identifications.  In reaching its decision, the Circuit Court stated:
I have not found that his testimony in this case will be helpful to
the jury in evaluating the evidentiary issues presented with
respect to the two eyewitness identifications. … With respect
to…Bailey, Defense counsel through cross examination will
have an opportunity to probe the officer's ability to observe,
remember, and recall the event in question including the
officer's ability to pay attention and any distraction the officer
was under. … Mr. Dower has already testified that he knows the
Defendant[.] … Thus, Mr. Dower's identification of the
Defendant in a photographic array did not depend on his ability
8
to encode, store, or retrieve the face of a stranger.  Indeed on
cross examination, Dr. Schretlen candidly admitted that his
entire direct examination would not pertain to a situation in
which an identification [wa]s made by a witness when the
person being identified is known to the witness. … [The
shooting] was a violent event for which the expert witness has
no data showing the impact of circumstances or the ability to
encode, store, and retrieve information in the human memory.
… The doctor has no studies or data to present in which a
witness has been tested for the events of observing a stressful
intervention or action. … The doctor further testified that every
individual would experience a different level of stress[.]
* * *
[W]ith respect to the testimony of the doctor on police officer or
trained observers' reactions with respect to human memory, the
doctor gave little to no testimony on direct.  There was one
question asked by the Defense attorney as to whether the studies
differed or what the studies showed about police officers.  The
doctor responded in a generality that there have been some
studies that have been shown that there is no appreciable
difference in the reaction [by] police officers or trained
observers [compared to] the other members of the public…  [I]n
coming to that conclusion…we don't have[:] the identification
of these studies, …the names of them[;]…the number of studies
that he's talking about with respect to police officers[;] …a
description of what these studies consisted of[; or] …the dates
of the discoveries of the studies. ... So with respect to the
observing ability of a police officer, we have little to no
information in terms of data or expert opinion from the doctor
to even apply to [this witness].
The judge allowed the prosecution to introduce into evidence the eyewitness identifications
made by Dower and Bailey.
At Bomar's trial, Bailey testified for the State and identified Bomar as the shooter.
Bailey authenticated the photographic array that was shown to him on October 26, 2004,
9
from which he had identified and signed Bomar's photo.  Through cross-examination of
Bailey, Defense counsel probed the following issues: (1) Bailey had been coming from a
nightclub (Melba's); (2) he drank a 12-16oz. beer at Melba's; (3) his truck's radio was on
when the shooting occurred; (4) there was a SUV approximately the same size as Bailey's
truck two cars in front of him on York Road; and (5) when Bailey exited his vehicle he was
cautious and apprehensive.  
Dower testified that Bomar was in fact not the person he had seen at the shooting and
refused to implicate him in the crime; but, he admitted he had told the police that Bomar was
the shooter.  Dower testified the shooter was a man with "deep dimples" and that police had
instructed him what to say during his taped interview and directed him to Bomar's picture in
the photo array.  Dower alleged that he had identified Bomar as the shooter and from the
photo array because he has poor eyesight, the sun was in his eyes, and he was experiencing
heroin withdrawal symptoms.
The jury subsequently convicted Bomar of second degree murder and use of a
handgun during the commission of a crime of violence or felony.  The judge sentenced
Bomar to imprisonment of thirty years for second degree murder and twenty years for the use
of a handgun in a crime of violence, which terms were to be served consecutively.
Bomar appealed the judgment to the Court of Special Appeals ("CSA") challenging
the Circuit Court’s exclusion of Dr. Schretlen’s expert testimony on grounds that it would
not have been helpful to a jury; the intermediate appellate court affirmed.  Bomas v. State,
181 Md. App. 204, 956 A.2d 215 (2008).  We granted Bomar’s Petition for Writ of Certiorari
2Maryland Rule 5-702 was adopted on December 15, 1993 as part of a new code of
evidence, and became effective July 1, 1994. 
10
to consider the following two questions: (1) should this Court reconsider its decision in
Bloodsworth v. State, 307 Md. 164, 512 A.2d 1056 (1986), and adopt a standard that favors
the admissibility of expert testimony on eyewitness memory identification in criminal cases
where the State’s primary evidence of guilt is an eyewitness identification of the accused, and
(2) did the trial court improperly exercise its discretion in finding that testimony from an
expert in the fields of neuropsychology and human memory would not be helpful to the jury
in evaluating eyewitness identifications of the defendant?  Bomar asks us to answer each
question in the affirmative.
DISCUSSION
I.
The Standard for Expert Testimony on Eyewitness Identification
Under Maryland Rule 5-702,
 Expert testimony may be admitted, in the form of an opinion or
otherwise, if the court determines that the testimony will assist
the trier of fact to understand the evidence or to determine a fact
in issue. In making that determination, the court shall determine
(1) whether the witness is qualified as an expert by knowledge,
skill, experience, training, or education, (2) the appropriateness
of the expert testimony on the particular subject, and (3) whether
a sufficient factual basis exists to support the expert testimony.
Although decided before our adoption of Rule 5-702,2 in Bloodsworth v. State, 307 Md. 164,
512 A.2d 1056 (1986), we applied a substantially similar common law rule, doing so
11
specifically in the context of the admissibility standard for, and the extent of courts’
discretion in, allowing or excluding expert testimony on eyewitness identifications.
Bloodsworth was convicted of first degree murder and related sexual offenses largely on the
strength of eyewitness testimony.  Id. at 166-70, 512 A.2d at 1057-59.  Similar to Bomar,
Bloodsworth argued that the trial court erred in refusing to allow an expert witness to testify
about the shortcomings of eyewitness identification.  Id. at 177, 512 A.2d at 1062-63.  The
expert witness in Bloodsworth offered to testify to the following:
. . . I would only be estimating what the research shows.
I don't have a particularly overall general condemnation of eye
witnesses at issue.
* * *
[E]ye witnesses are really confronted with a difficult
situation, and when the circumstances add up to a very difficult
challenge to the memory system, these are things that can
happen to various parts of their testimony and various parts of
their identification, and testing methods…I see as simply a tool,
and the checklist is…provided to the jury so that they can
essentially assess what…the filter of the scientist would say
about a given test.
Id. at 177-78, 512 A.2d at 1062.  The trial judge excluded the expert's testimony stating:
I am concerned [about] the possibility [that] admitting the
evidence would tend to confuse or mislead the jury.  This is not
just a matter of usurping the province of the jury, although it is
in my judgment most certainly that, it is also that such testimony
is of little value in aiding the jury in this case.  I'm not persuaded
that the testimony will be helpful to the jury in understanding
the evidence in this case.
* * *
3The Frye-Reed test originated from two cases:  Frye v. United States, 293 F. 1013
(D.C. Cir. 1923), superseded by FED. R. EVID. 702, and Reed v. State, 283 Md. 374, 391 A.2d
364 (1978).  Frye held that courts may admit expert testimony if it is based on a scientific
principle or discovery that has general acceptance in the scientific community.  293 F. at
1014.  The principle expressed in Frye became incorporated into Maryland law with the Reed
decision.  This Court held,
 
before a scientific opinion will be received as evidence at trial,
the basis of that opinion must be shown to be generally accepted
as reliable within the expert's particular scientific field. Thus,
according to the Frye standard, if a new scientific technique's
validity is in controversy in the relevant scientific community,
or if it is generally regarded as an experimental technique, then
expert testimony based upon its validity cannot be admitted into
evidence.
Reed, 283 Md. at 381, 391 A.2d at 368.
12
It seems to me that the reliability of the witnesses and the
identification witnesses is better tested by the cathartic effect of
cross-examination than by the opinion of an expert.
Id. at 178, 512 A.2d at 1063.  The trial judge also concluded that the proffered testimony
failed the Frye-Reed test3 because the defense failed to present evidence showing that the
expert testimony on eyewitness identification "has general acceptance in the relevant
scientific community."  Id. at 179, 512 A.2d at 1063.  Finally, the trial judge held:
[E]ven if it were a technique generally accepted in the
relevant scientific community, the proffer is not sufficient to
persuade me first, exactly what is being offered to the jury other
than some generalized explanation of the studies that have been
made.  Nothing that has been proffered suggests that it will be
helpful.
* * *
[I]t may usurp the jury's province in determining the
4 In Brady v. Maryland, 373 U.S. 83, 87, 83 S. Ct. 1194, 1196-97 (1963), the Supreme
Court held “that the suppression by the prosecution of evidence favorable to an accused upon
request violates due process where the evidence is material either to guilt or to punishment,
irrespective of the good faith or bad faith of the prosecution.”  In Bloodsworth, the defendant
filed a discovery motion requesting the identity of other possible police suspects, information
on photo spreads or reports to law enforcement authorities suggesting someone other than
the defendant had committed the crime, and all the police officers' notes for this case.
Bloodsworth v. State, 307 Md. 164, 171, 512 A.2d 1056, 1060 (1986).  Subsequently, a
report from a detective regarding another possible suspect was not made available to
Bloodsworth until sometime between the trial and the sentencing phase.  Id. at 172, 512 A.2d
at 1060.  We held that the fact that the prosecution was not in physical possession of the
report was "immaterial" and that the "undisclosed report is sufficient to undermine
confidence in the outcome of the trial."  Id. at 174-76, 512 A.2d at 1060-61.
13
reliability of the identification in this case . . . .
Id. at 179, 512 A.2d at 1063.  We upheld the trial judge's decision to exclude the expert's
testimony but remanded the case to the Circuit Court due to Brady violations.4  Bloodsworth,
307 Md. at 171-76, 512 A.2d at 1067.  
In addition, we held "that the Frye-Reed test was not properly applicable to [expert
testimony on eyewitness identification.]" Id. at 184, 512 A.2d at 1066.  In upholding the
decision we held that the proper standard for the admissibility of expert testimony on
eyewitness reliability is “‘whether [the expert's] testimony will be of real appreciable help
to the trier of fact in deciding the issue presented.’” Id., 512 A.2d at 1066 (quoting Shivers
v. Carnaggio, 223 Md. 585, 165 A.2d 898 (1960)).  Further, we held that “‘[t]he
admissibility of expert testimony is a matter largely within the discretion of the trial court,
and its action in admitting or excluding such testimony will seldom constitute a ground for
reversal.’” Bloodsworth, 307 Md. at 185, 512 A.2d at 1067 (quoting Raithel v. State, 280 Md.
5See United States v. Rodriguez-Berrios, 573 F.3d 55, 71-72 (1st Cir. 2006); United
States v. Brownlee, 454 F.3d 131, 141-44 (3d Cir. 2006); United States v. Martin, 391 F.3d
949, 954 (8th Cir. 2004); United States v. Lumpkin, 192 F.3d 280, 288-89 (2d Cir. 1999);
(continued...)
14
291, 372 A.2d 1069 (1977)). 
Bomar now urges us to reevaluate the standard adopted in Bloodsworth regarding
expert testimony on eyewitness identification.  He argues that such expert testimony should
be presumptively admissible, or at least be favored, especially in cases like this one, where
eyewitness testimony forms the foundation of the State's case.   For this proposition, he
argues that (1) Bloodsworth discouraged the admission of expert testimony on eyewitness
identification; (2) many wrongful convictions are due to eyewitness misidentifications,
causing many jurisdictions to favor the admissibility of expert testimony on the reliability of
eyewitness identifications; and (3) expert testimony on eyewitness identification should be
presumptively helpful and under this standard the trial judge erred in not admitting the
proffered expert testimony.  
Before assessing Bomar’s arguments, we first look for guidance from other
jurisdictions that have grappled with how to handle expert testimony on eyewitness
identification.  In McMullen v. State, 714 So. 2d 368, 370-71 (Fla. 1998), the Supreme Court
of Florida divided the various jurisdictional approaches on this issue into categories,
“discretionary” and “prohibitory.”  The discretionary approach grants the trial court
discretion as to whether to admit such testimony and appears to be the majority view on both
the federal5 and state6 levels that have considered the question.  Id. at 370.  Other
(...continued)
United States v. Hall, 165 F.3d 1095, 1104-1106 (7th Cir. 1999); United States v. Smith, 156
F.3d 1046, 1052-54 (10th Cir. 1998); United States v. Rincon, 28 F.3d 921, 926 (9th Cir.
1994); United States v. Harris, 995 F.2d 532, 534-35 (4th Cir. 1993).
6See Ex parte Williams, 594 So. 2d 1225, 1226-27 (Ala. 1992); Jones v. State, 862
S.W.2d 242, 244 (Ark. 1993); State v. McClendon, 730 A.2d 1107, 1115 (Conn. 1999);
Green v. United States, 718 A.2d 1042, 1050-55 (D.C. 1998); McMullen v. State, 714 So.2d
368, 370-72 (Fla. 1998); People v. Enis, 564 N.E.2d 1155, 1161-63 (Ill. 1990); State v.
Gaines, 926 P.2d 641, 646-49 (Kan. 1996); State v. Rich, 549 A.2d 742, 743-44 (Me. 1988);
Commonwealth v. Santoli, 680 N.E.2d 1116, 1118-21 (Mass. 1997) (applying abuse of
discretion standard while offering some suggestion that it would favor the admission of
expert testimony when the State has no other corroborating evidence); State v. Barlow, 541
N.W.2d 309, 313 (Minn. 1995); White v. State, 926 P.2d 291, 292 (Nev. 1996); State v.
Knox, 337 S.E.2d 154, 156-57 (N.C. Ct. App. 1985); State v. Sabetta, 680 A.2d 927, 932-33
(R.I. 1996); State v. Copeland, 226 S.W.3d 287, 298-300 (Tenn. 2007); Rodriguez v.
Commonwealth, 455 S.E.2d 724, 726-28 (Va. Ct. App. 1995); State v. Percy, 595 A.2d 248,
252-53 (Vt. 1990); State v. Hernandez, 794 P.2d 1327, 1331-33 (Wash. Ct. App. 1990),
disapproved of on other grounds, State v. Kjorsvik, 812 P.2d 86 (Wash. 1991); Engberg v.
Meyer, 820 P.2d 70 (Wyo. 1991).
7See United States v. Smithers, 212 F.3d 306, 317 (6th Cir. 2000) (discretionary
standard but should be admitted when there is no other inculpatory evidence); Skamarocius
v. State, 731 P.2d 63, 65-67 (Alaska. Ct. App. 1987); People v. Jones, 70 P.3d 359, 374-75
(Cal. 2003); People v. Campbell, 847 P.2d 228, 232-35 (Colo. Ct. App. 1992); Johnson v.
State, 526 S.E.2d 549, 552-53 (Ga. 2000); State v. Wright, 206 P.3d 856, 861-64 (Idaho Ct.
App. 2009); Commonwealth v. Christie, 98 S.W.3d 485, 488 (Ky. 2002); State v. Carter, 522
So.2d 1100, 1109 (La. App. 1988) ("Where the key issue is the accused's identity as the
perpetrator, rather than whether the crime was committed, the state is required to negate any
reasonable probability of misidentification.")(citations omitted); State v. LeGrand, 867
N.E.2d 374, 375-76 (N.Y. 2007); State v. Whaley, 406 S.E.2d 369, 371-72 (S.C. 1991).
Other jurisdictions may fall in this category, but have not yet confronted the question of
whether expert testimony should be admissible when no other corroborating evidence exists.
15
jurisdictions embrace a discretionary approach generally, but either require or favor the
admission of expert testimony on eyewitness identification when the prosecution's case relies
solely on eyewitness testimony.7  Some jurisdictions appear to generally disfavor expert
8See United States v. Alexander, 816 F.2d 164, 167 (5th Cir. 1987), cert. denied, 493
U.S. 1069, 110 S. Ct. 1110 (1990) (generally inadmissible except when the case depends
primarily on eyewitness identification); State v. Chapple, 660 P.2d 1208, 1223-23 (Ariz.
1983).
9See United States v. Smith, 122 F.3d 1355, 1357-59 (11th Cir. 1997); State v.
Goldsby, 650 P.2d 952, 953-54 (Or. Ct. App. 1982); Commonwealth v. Simmons, 662 A.2d
621, 630-31 (Pa. 1995).
16
testimony on eyewitness identification, but favor it when the State has no substantial
corroborating evidence.8  Finally, there is a prohibitory approach which excludes all expert
testimony on eyewitness identification. To our knowledge, only three jurisdictions have
retained this per se exclusion.9 Id. at 371.
Bomar argues that Bloodsworth discourages the admission of expert testimony on
eyewitness identification because "the opinion advances all the arguments against the
admissibility of expert testimony, and provides no countervailing observations which would
educate trial judges as to circumstances in which expert testimony on eyewitness reliability
would be helpful."  To support his argument, Bomar draws attention to our observation in
Bloodsworth that, "[t]he vast majority of courts have rejected [expert testimony on
eyewitness identification,]" id. at 181, 512 A.2d at 1064, and the Court’s reliance on United
States v. Amaral, 488 F.2d 1148 (9th Cir. 1973), and State v. Porraro, 404 A.2d 465 (R.I.
1979), two cases that upheld the exclusion of such evidence.  We quoted Amaral for the
proposition that “‘[o]ur legal system places primary reliance for the ascertainment of truth
on the test of cross-examination’” and that “‘[i]t is the responsibility of counsel during
cross-examination to inquire into the witness' [sic] opportunity for observation, his capacity
17
for observation, his attention and interest and his distraction or division of attention.’”
Bloodsworth, 307 Md. at 182, 512 A.2d at 1065 (quoting Amaral, 488 F.2d at 1153)
(citations omitted).  We also referenced Porraro, in which the Supreme Court of Rhode
Island upheld the trial judge's exclusion of a psychology professor's testimony on eyewitness
identification because of a fear “‘it would effectively invade the province of the jury’” and
that “‘admitting this testimony would open a floodgate whereby experts would testify on
every conceivable aspect of a witness' [sic] credibility.’” Bloodsworth, 307 Md. at 183, 512
A.2d at 1065 (quoting Porraro, 404 A.2d at 471).  We then quoted the following holding in
Porraro, which was similar to the decision in Amaral:
“We are persuaded that the subject matter of the proffered
testimony in this case, the trustworthiness in general of
eyewitness observations, was not beyond the ken of the jurors
and therefore the trial justice did not abuse his discretion in
excluding this evidence. Through cross-examination, defense
counsel was able to probe into the witness' [sic] capacity and
opportunity for observation, her attention, interest and
distraction. The jury was perfectly capable of assessing the
witness' [sic] credibility by weighing the inconsistencies and
deficiencies elicited in cross-examination.”
Bloodsworth, 307 Md. at 183, 512 A.2d at 1065 (quoting Porraro, 404 A.2d at 465).  We
agree with Bomar that the Bloodsworth opinion strikes a negative tone with respect to expert
testimony on eyewitness identification.  But this does not mean that Bloodsworth was
wrongly decided or that we should depart from the “real appreciable help” to the jury
standard for admission that was applied in that case.  We will be sure, though, to carefully
examine the record here to ascertain whether that negative tone influenced the trial court’s
18
ruling excluding Dr. Schretlen’s testimony.  
First we consider Bomar’s thesis that such expert testimony should be presumptively
admissible.  Quoting an article published in an American Bar Association journal, Richard
S. Schmechel, et al., Beyond the Ken? Testing Jurors’ Understanding of Eyewitness
Reliability Evidence, 46 JURIMETRICS 177, 184, Bomar defends his “presumptively
admissible” theory by arguing that the standard of review for trial judges' decisions on expert
testimony is “‘vacuous[,]’” makes a lower court's decision “‘de facto final’” or grants the
lower court “unfettered” discretion, and “insulates the decision not to allow such experts
within an extremely deferential standard of review.”  Bomar points out that the trial judge
in Bloodsworth, on remand, again precluded the expert testimony he sought to introduce and
again a jury convicted Bloodsworth of murder primarily on the basis of eyewitness
identification.  See Bloodsworth v. State, 76 Md. App. 23, 33, 543 A.2d 382, 387 (1988).  He
observes, moreover, that DNA testing in 1993 exonerated Bloodsworth of this crime.  See
The 
Innocence 
Project, 
Know 
the 
Cases: 
Kirk 
Bloodsworth,
http://www.innocenceproject.org/ Content/54.php (last visited Jan. 04, 2010).
Bomar's second contention is that the volume of wrongful convictions based on
eyewitness misidentifications impels this Court to encourage the admission of expert
testimony on eyewitness identification.  Bomar predicates his argument on studies showing
that a substantial number of individuals who were convicted of a crime, but later exonerated
by DNA evidence, were mistakenly identified by at least one eyewitness.  For example, the
Third Circuit in United States v. Brownlee reviewed literature on eyewitness reliability and
19
observed:
The recent availability of post-conviction DNA tests
demonstrate that there have been an overwhelming number of
false convictions stemming from uninformed reliance on
eyewitness misidentifications.  In 209 out of 328 cases (64%) of
wrongful convictions identified by a recent exoneration study,
at least one eyewitness misidentified the defendant.  In fact,
mistaken eyewitness identifications are responsible for more
wrongful convictions than all other causes combined.
454 F.3d 131, 141-42 (3d Cir. 2006) (internal quotation marks and citations omitted); see
also State v. Copeland, 226 S.W.3d 287, 299-300 (Tenn. 2007) (reviewing literature
addressing limitations of eyewitness identification evidence); The Maryland Commission on
Capital Punishment, Final Report to the General Assembly 64, Dec. 12, 2008 (citing the
prevalence of erroneous eyewitness identifications and subsequent wrongful convictions as
a reason to abolish the death penalty in Maryland); The Innocence Project, Fact Sheet on
Post-Conviction DNA Exonerations, available at http://www.innocenceproject.org/
news/Fact-Sheets.php (finding that "Eyewitness [m]isidentification [t]estimony was a factor
in 74 percent of post-conviction DNA exoneration cases in the U.S. . . . .") (last visited Jan.
04, 2010).
Bomar maintains that because of the apparently frequent convictions based on
eyewitnesses' misidentifications, "[o]ther jurisdictions have tempered the judicial hostility
towards admitting . . . expert testimony on eyewitness reliability in vogue when Bloodsworth
was decided, and the decisive trend now recognizes that expert testimony on eyewitness
reliability is a necessary safeguard against wrongful conviction."  He argues that the majority
20
of cases treat expert testimony on eyewitness reliability as "presumptively helpful to the jury"
when the State's case is based primarily on eyewitness testimony.  In support of this trend,
Bomar offers United States v. Smithers, 212 F.3d 306 (6th Cir. 2000); Johnson v. State, 526
S.E.2d 549 (Ga. 2000); and Copeland, 226 S.W.3d at 301.
In Smithers, the Sixth Circuit considered whether the district court abused its
discretion in refusing to allow an expert on eyewitness identification.  In examining the
means by which courts consider such testimony, the court appraised the development of
expert testimony on eyewitness reliability as follows:
Courts' treatments of expert testimony regarding eyewitness
identification has experienced a dramatic transformation in the
past twenty years and is still in a state of flux.  Beginning in the
early 1970's, defense attorneys began to bring expert testimony
into the courtroom.  Then, courts were uniformly skeptical about
admitting such testimony, elaborating a host of reasons why
eyewitness experts should not be allowed to testify.
* * *
This trend shifted with a series of decisions in the 1980's, with
the emerging view that expert testimony may be offered, in
certain circumstances, on the subject of the psychological
factors which influence the memory process. . . . This
jurisprudential trend is not surprising in light of modern
scientific studies which show that, while juries rely heavily on
eyewitness testimony, it can be untrustworthy under certain
circumstances.
Recognizing the dichotomy between eyewitness errors and
jurors' reliance on eyewitness testimony, this Circuit has held
that expert testimony on the subject of eyewitness identification
is admissible.
212 F.3d at  311-12 (citations and footnote omitted).  The Smithers court held that the district
10 In its analysis, the Sixth Circuit applied the test adopted in Daubert v. Merrell Dow
Pharmaceuticals, 509 U.S. 579, 113 S. Ct. 2786 (1993) and Kumho Tire Company v.
Carmichael, 526 U.S. 137, 119 S. Ct. 1167 (1999):
Daubert thus requires trial courts to perform a two-step inquiry.
First, the court must determine whether the expert's testimony
reflects scientific knowledge, that is, the court must make a
preliminary assessment of whether the reasoning or
methodology underlying the testimony is scientifically valid and
of whether that reasoning or methodology properly can be
applied to the facts in issue.  Second, the court must ensure that
the proposed expert testimony is relevant to the task at hand and
will serve to aid the trier of fact.
* * *
The Supreme Court in Kumho indicated that the standards set
forth in Daubert, depending on the particular circumstances of
the particular case, should be flexibly applied.
* * *
While it is true that several post-Daubert eyewitness
identification cases have found that the exclusion of the
testimony was not an abuse of discretion . . . the lesson from
these cases is not that expert testimony on eyewitness
identification is never appropriate; rather, the cases indicate that
courts must consider whether the testimony would be helpful or
confusing to the jury.
* * *
Although the decision of whether to admit a witness's testimony
(continued...)
21
court improperly excluded the proffered expert testimony because (1) the district judge
excluded the expert's testimony because it "makes it a more interesting case" and (2) the
district court failed to follow established guidelines for admitting such evidence.10  Id. at
(...continued)
is left to the sound discretion of the trial court, a trial court
cannot make an arbitrary decision.
Smithers, 212 F.3d at 313-15 (internal quotation marks and citations removed).
22
314-15.   The Sixth Circuit also held that "expert testimony should be admitted in the precise
situation presented to the trial court in this case–that is, when there is no other inculpatory
evidence presented against the Defendant with the exception of a small number of eyewitness
identifications."  Id. at 317.
Bomar maintains that the reliability of eyewitness testimony is beyond the ken of
jurors, citing Smithers, 212 F.3d at 312 n.1, 316, which states that "[t]oday, there is no
question that many aspects of perception and memory are not within the common experience
of most jurors, and in fact, many factors that affect memory are counter-intuitive" and that
“[j]urors tend to overestimate the accuracy of eyewitness identifications because they often
do not know the factors they should consider when analyzing this testimony.”  Bomar
reiterates, citing Copeland, that expert testimony is needed to sensitize jurors to eyewitness
errors:
[R]esearch over the past thirty years has shown that expert
testimony on memory and eyewitness identification is the only
legal safeguard that is effective in sensitizing jurors to
eyewitness errors.  Studies have shown that erroneous
identification accounted for as much as eighty-five percent of
the convictions of those individuals later exonerated by DNA
testing.
*     *     *
23
Further, 
the 
research 
also 
indicates 
that 
neither
cross-examination nor jury instructions on the issue are
sufficient to educate the jury on the problems with eyewitness
identification . . . .
Copeland, 226 S.W.3d at 299-300 (quotation marks and citations omitted); see also
Brownlee, 454 F.3d at 141-42 (reviewing literature and stating that “‘jurors seldom enter a
courtroom with the knowledge that eyewitness identifications are unreliable’”) (citations
omitted).
Bomar's third argument calls for us to consider expert testimony on eyewitness
identification presumptively helpful in cases where there is no other evidence to corroborate
the eyewitness identification.  For this proposition, Bomar relies on two cases: Johnson, 526
S.E.2d at 549, and State v. LeGrand, 867 N.E.2d 374 (N.Y. 2007).  According to Bomar, in
Johnson, the Supreme Court of Georgia adopted a presumptive admissibility standard for
expert opinion on eyewitness testimony where a state's case against a defendant rests
primarily on the eyewitness identification, in holding:
Where eyewitness identification of the defendant is a key
element of the State's case and there is no substantial
corroboration of that identification by other evidence, trial
courts may not exclude expert testimony without carefully
weighing whether the evidence would assist the jury in assessing
the reliability of eyewitness testimony and whether expert
eyewitness testimony is the only effective way to reveal any
weakness in an eyewitness identification.  However, the
admission or exclusion of this evidence lies within the sound
discretion of the trial court, whose decision will not be disturbed
on appeal absent a clear abuse of discretion.
526 S.E.2d at 552-53 (quotation marks and citations and omitted).  Similarly in LeGrand, the
11Maryland Rule 5-401 defines "relevant evidence" as evidence “having any
tendency to make the existence of any fact that is of consequence to the determination of
the action more probable or less probable than it would be without the evidence.”
24
Court of Appeals of New York held:
[W]here the case turns on the accuracy of eyewitness
identifications and there is little or no corroborating evidence
connecting the defendant to the crime, it is an abuse of
discretion for a trial court to exclude expert testimony on the
reliability of eyewitness identifications if that testimony is (1)
relevant to the witness's identification of defendant, (2) based on
principles that are generally accepted within the relevant
scientific community, (3) proffered by a qualified expert and (4)
on a topic beyond the ken of the average juror. . . . [T]rial courts
generally have the power to limit the amount and scope of
evidence presented . . . .
867 N.E.2d at 375-76.  
Bomar believes a standard where expert testimony is presumptively helpful to a jury
will strike "the proper balance between the trial judge's traditional discretion in evaluating
the admissibility of evidence and providing a proper safeguard against wrongful conviction."
Under Bomar's proposed standard, "[t]rial judges would still have discretion to exclude the
testimony, but only if the party seeking to exclude the expert demonstrates that the opinions
are not helpful because they do not pertain to the situation at hand."  Bomar also argues this
standard would be consistent with Bloodsworth, though the end result would differ, and with
Maryland Rule 5-401, which defines relevant testimony.11 
We agree with Bomar that jurisdictions have trended toward the admissibility of
expert testimony on eyewitness reliability and we recognize that scientific advances since
12The applicability of Frye-Reed to expert testimony on eyewitness identification was
(continued...)
25
Bloodsworth may assist juries in evaluating eyewitness testimony.  We appreciate that
scientific advances have revealed (and may continue to reveal) a novel or greater
understanding of the mechanics of memory that may not be intuitive to a layperson.   Thus,
it is time to make clear that trial courts should recognize these scientific advances in
exercising their discretion whether to admit such expert testimony in a particular case. 
Nonetheless, some of the factors of eyewitness identification are not beyond the ken
of jurors. For example, the effects of stress or time are generally known to exacerbate
memory loss and, barring a specific set of facts, do not require expert testimony for the
layperson to understand them in the context of eyewitness testimony.  In recognition of this,
we believe, consistent with our past holdings, that a flexible standard that can properly gauge
the state of the scientific art in relation to the specific facts of the case is best. 
Accordingly, notwithstanding the negative tone of the Bloodsworth decision, the
substantive standard for admissibility set forth was not wrong, and indeed is consonant with
the current majority view.  Thus, we reiterate the following test for the admissibility of expert
testimony on eyewitness identification: “‘whether his [or her] testimony will be of real
appreciable help to the trier of fact in deciding the issue presented[;]’” the application of this
test is “‘a matter largely within the discretion of the trial court[.]’” Bloodsworth, 307 Md. at
184, 185, 512 A.2d at 1066, 1067 (citations omitted). This standard comports with the
general rule on expert testimony set forth in Rule 5-702. 12
(...continued)
not argued or decided by the court below.  As noted earlier, Bloodsworth disallowed the
application of Frye-Reed to this type of evidence because that test had only been applied in
limited circumstances. 307 Md. at 184, 512 A.2d at 1066 (“Our own use of what we
denominate as the Frye-Reed test has been confined to ‘voice prints’ in Reed and to
hypnosis[.]”).  Since Bloodsworth, we have applied the Frye-Reed test to other types of
evidence.  See Blackwell v. Wyeth, 408 Md. 575, 585-93, 971 A.2d 235, 242-45 (2009)
(applying Frye-Reed to expert testimony concerning the causal connection between
thimerosol-laden vaccines and autism and reviewing cases involving Frye-Reed’s application
to testimony concerning statistical methods, Comparative Bullet Lead Analysis, and biotoxic
illness).  Other jurisdictions have applied this test or the Daubert test to expert testimony on
eyewitness identification and have found such evidence to be admissible.  See, e.g., Legrand,
867 N.E.2d at 458-59. We do not address the applicability of Frye-Reed to the testimony
offered in this case. 
13For example, the Supreme Court of Tennessee in Copeland overturned the precedent
it set in State v. Coley, 32 S.W.3d 831, 833-38 (Tenn. 2000), stating, “we have chosen to
overrule Coley's conclusion that no one, regardless of credentials or experience and no matter
how questionable the evidence, can provide testimony on the issue of eyewitness
identification[.]” 226 S.W.3d at 301.  The Copeland court did not, however, recognize a
presumptive admissibility standard for testimony on eyewitness identification, though it
noted scientific advances that may provide some insight to eyewitness identification.  The
Supreme Court of Georgia in Johnson, moreover, rejected a per se exclusion of expert
testimony on eyewitness identification and then declined to adopt a standard “that a trial
court necessarily abuses its discretion by refusing to admit qualified, pertinent expert
(continued...)
26
The trial court’s discretion is sufficiently circumscribed by Maryland Rule 5-702,
which outlines specific criteria to determine whether to admit the proffered expert testimony.
We decline Bomar’s proposed standard because we do not want to hamper the trial court's
ability to evaluate proffered expert testimony on a case-by-case basis.  Despite the increased
acceptance of such evidence, most jurisdictions have not embraced a presumption of
admissibility.  Rather, the trend has largely been one of jurisdictions abandoning blanket
exclusion of such expert testimony.13  A trial judge must have the ability to determine
(...continued)
testimony in any case where no substantial evidence exists to corroborate eyewitness
identification testimony.” 526 S.E.2d at 552.  The Johnson court merely suggested that if
there is no other corroborating evidence, “trial courts may not exclude expert testimony
without carefully weighing whether the evidence would assist the jury in assessing the
reliability of eyewitness testimony and whether expert eyewitness testimony is the only
effective way to reveal any weakness in an eyewitness identification.” Id. at 552 (emphasis
added).
14Maryland Criminal Pattern Jury Instruction (MPJI-Cr) 3:10 addresses the credibility
of witnesses:
(continued...)
27
whether proffered testimony has a credible foundation and is relevant to the facts of a given
case.  Rule 5-702 entrusts the trial court with the task of determining whether an expert is
qualified to give testimony about an issue, whether there is a foundation for the expert's
proffered testimony, and the relevance of the proffered testimony.  We see no reason to shift
the burden of demonstrating the Rule 5-702 elements away from the one who presents the
expert to the court.
Expert testimony is not the only means to educate juries about the vagaries of
eyewitness testimonies and safeguard against wrongful convictions based on
misidentifications.   In some cases, other trial components such as cross-examination, closing
arguments, and jury instructions, can provide the jury with sufficient information to evaluate
the reliability of eyewitness identifications. Indeed, it might be an appropriate time for the
Maryland Criminal Pattern Jury Instruction Committee to evaluate whether its current rule
on witnesses (MPJICr 3:10) should be modified in light of the studies about eyewitness
testimony, and the scientific advances in this area.14    
(...continued)
You are the sole judge of whether a witness should be
believed.  In making this decision, you may apply your own
common sense and every day experiences.
* * *
You should consider such factors as:
(1)  the witness's behavior on the stand and manner of
testifying;
(2)
did the witness appear to be telling the truth?
(3)
the witness's opportunity to see or hear the things about
which testimony was given;
(4)
the accuracy of the witness's memory;
(5)
does the witness have a motive not to tell the truth?
(6)
does the witness have an interest in the outcome of the
case?
(7)
was the witness's testimony consistent?
(8)
was the witness's testimony supported or contradicted by
evidence that you believe? and
(9)
whether and the extent to which the witness's testimony in
the court differed from the statements made by the witness
on any previous occasion.
MPJI-Cr 3:30  addresses a witness’s identification of the defendant:
You have heard evidence regarding the identification of the
defendant as the person who committed the crime.  In this
connection, you should consider the witness's opportunity to
observe the criminal act and the person committing it, including
the length of time the witness had to observe the person
committing the crime, the witness's state of mind and any other
circumstance surrounding the event.  You should also consider
the witness's certainty or lack of certainty, the accuracy of any
prior description, and the witness's credibility or lack of
credibility, as well as any other factor surrounding the
identification.
(continued...)
28
(...continued)
Indeed, the trial judge in this case delivered both of the instructions above.
29
A presumptively helpful standard in cases relying on eyewitness identification could
unnecessarily complicate a case by encouraging a “battle of the experts.”  Dueling experts
could interject differing interpretations of statistics and scientific studies on identification,
leaving the jury more confused than aided by the expert opinions.  Further, we do not want
to force experts upon a court where, as here, the expert’s testimony would not have been
helpful to a jury.  Thus, we reject holding expert testimony on eyewitness reliability to any
other standard other than the abuse of discretion standard.  Whether the prosecution's case
rests solely on eyewitness identification or not, the probative value of expert testimony on
eyewitness identification and how much such testimony can actually help the jury in the case
before it must be carefully weighed by the court on a case-by-case basis.
II.
The Circuit Court's Decision in This Case
We will now apply the “appreciable help to the trier of fact” test to the Circuit Court’s
decision to exclude Dr. Schretlen's expert testimony on eyewitness identification, giving
deference to the trial court’s exercise of discretion, and taking care to determine whether the
court adopted a negative view of such testimony in light of Bloodsworth.  We apply this test
in the course of considering Bomar’s arguments in favor of admission. 
Bomar claims the proffered expert testimony would have been helpful to the jury
30
because it would inform the jury how (1) a "trained observer" does not recall an event more
accurately than a lay person; (2) confidence is not necessarily correlated with accuracy; (3)
a memory tends to fade over time in a "curvilinear" fashion; (4) stress can adversely affect
one's memory; and (5) the manner a photo array is presented to an eyewitness can lead to
false identifications. 
Bomar argues Dr. Schretlen's testimony would have informed jurors, "contrary to
popular belief[,]" that a "trained observer" does not have a better memory than a layperson.
In support of this opinion, Bomar also cites statements from a series of articles.  See
Schmechel, et al., 46 JURIMETRICS at 200; Timothy P. O'Toole, et al., District of Columbia
Public Defender Survey: What Do Jurors Understand About Eyewitness Reliability, THE
CHAMPION, April 2005, at 29.  But Dr. Schretlen did not rely on any of the articles or studies
therein as the basis of his opinion.  In fact, the record is devoid of any specific study whose
data Dr. Schretlen relied on to form his opinion on this issue.
The CSA regarded Dr. Schretlen's testimony as “vague” and found the motions judge's
exclusion of it “understandabl[e].”  Bomas, 181 Md. App. at 217, 956 A.2d at 223.  We
agree; the testimony is extremely general, vague, and inconclusive.  Further, the witness
offered nothing to support his general statements.  The Circuit Court was well within the
realm of its discretion in  excluding this testimony in light of the third prong of Rule 5-702,
which calls for a “sufficient factual basis” to support the expert's testimony.  See Buxton v.
Buxton, 363 Md. 634, 651, 770 A.2d 152, 162 (2001) (experts’ testimony properly admitted
when “both described the basis for their assumptions and calculations”); Young v. State, 388
31
Md. 99, 119 n.11, 879 A.2d 44, 56 n.11 (2005) (“Testimony describing the methods
employed in examining the DNA samples and calculating the match probabilities can lay the
foundation for the trial court to determine that a sufficient factual basis exists for the DNA
expert to testify to the source of the DNA evidence.”) 
Bomar next suggests that the court erred in precluding Dr. Schretlen's testimony on
the lack of a correlation between a witness's confidence and accuracy.  But during his
testimony, Dr. Schretlen described conflicting conclusions drawn by studies in this area.  He
even described scientific research on the relationship between confidence and accuracy as
"mixed" and expanded on this, stating:
Some studies show that how confident an eye witness is does
predict the accuracy of his or her memory in that more confident
eyewitnesses tend to be more accurate.  Other studies have
shown that there isn't a relationship between the two. . . . Under
some circumstances, confidence is a pretty good predictor.
The trial court had discretion to exclude this testimony under Rule 5-702 because it offered
nothing of value to the jury.  Testimony based on unspecified studies with conflicting
conclusions regarding the correlation between confidence and accuracy in identifying
persons would offer little to no help to the jury in evaluating Bailey’s identification of
Bomar.  
On the effect of time on memory, the motions court was entitled to find that, under
these circumstances, Dr. Schretlen's testimony would have been unhelpful to a jury or within
the common knowledge of a layperson.  The effect of time on memory is something, as the
doctor concedes, within the ken of jurors.   The "curvilinear" relationship of the "forgetting
15Bomar also argues that Dr. Schretlen's testimony should have been admitted because
it would inform the jury about the "relative judgment" phenomenon.  This term refers to
feedback a putative witness receives from the administrator of a photo array, which causes
the witness to misidentify persons in the array (because the witness is likely to select the
individual who most resembles the suspect).  Citing a single study, Dr. Schretlen opined that
(continued...)
32
curve," whereby an individual tends to lose the most information about an event in the first
moments post-exposure, which may not be known by jurors, would not have been helpful to
the jury here because Bailey and Dower made their identifications six months after the
shooting.  The date of their identification places their recollections of the shooting in the part
of the memory curve that is intuitive to a layperson.
Dr. Schretlen's proffered opinion on the effect of stress on memory also would have
been confusing to a jury.  Dr. Schretlen's testimony insufficiently related to the facts of the
case because the lone study he cited involved individuals who had directly experienced the
high stress event, whereas Bailey and Dower witnessed the shooting at a distance.  The
testimony also shed little light on how to quantify the stress levels of the eyewitnesses who
are not the subjects of the stress-inducing event.  Indeed, according to Dr. Schretlen,
individuals experience stress differently.  Dr. Schretlen also conceded that low to moderate
levels of stress might actually be beneficial to memory.  Other than the prisoners of war
study, Dr. Schretlen acknowledged that very few studies of stress during violent events have
been performed because such studies would not gain academic approval to proceed.  For
these reasons, the motions court was warranted in determining that Dr. Schretlen's testimony
on the effects of stress would not have been helpful to a jury.15
(...continued)
where a perpetrator is not present in a photo array, witnesses will select the person who most
closely resembles the perpetrator; where the perpetrator is present in the photo array, “the
eyewitnesses are most likely to identify the perpetrator because he looks most like himself.”
We shall not consider this issue.  It was neither raised in the CSA, nor included in the petition
for certiorari.  See Md. Rule 8-131(b).
33
CONCLUSION
As Bomar points out, the Supreme Court over forty years ago stated “[t]he vagaries
of eyewitness identification are well-known; the annals of criminal law are rife with instances
of mistaken identification.” United States v. Wade, 388 U.S. 218, 228, 87 S. Ct. 1926, 1933
(1967).  This piece of judicial wisdom has not abated with time, and we are sensitive to the
perils of such testimony.  With this in mind, we reiterate that trial courts, in considering the
admission of expert testimony regarding eyewitness observation and memory,  should
recognize scientific advances that have led to a greater understanding of the mechanics of
memory that may not be intuitive to a layperson.  
Our examination of the record in this case assures us, however, that the trial court
demonstrated that it was cognizant that an expert might well possess reliable and helpful
information to impart to a jury on the subject of eyewitness testimony.  There is no indication
that the Circuit Court excluded Dr. Schretlen's testimony on account of any bias against
expert testimony on the subject of eyewitness observation and memory.  Rather, it carefully
considered the proffered testimony's foundation, relevance to the facts of the case, and
helpfulness to the jury.  The Circuit Court was entitled to conclude, as it did, that the topics
covered by the proffered testimony were inadmissible for at least one  of the following
34
reasons: the testimony (1) lacked adequate citation to studies or data, (2) insufficiently
related to the identifications at issue, and/or (3) addressed concepts that were not beyond the
ken of laypersons.  Because of these deficiencies, the court had ample basis to conclude that
the proffered testimony would have been unhelpful to the jury.
JUDGMENT OF THE COURT OF
SPECIAL APPEALS AFFIRMED; COSTS
TO BE PAID BY PETITIONER.