ACCURACY OF WITNESS EVIDENCE
There are many cases in which the testimony of an eyewitness makes the difference between
conviction and acquittal. Such testimony is crucial to the criminal justice system because it is
often the most compelling evidence presented in court.
● Case study example: London Bombings- On July 2005, a terrorist attack took place in
London and around 30 buses were blown at the same time tube trains were blown. After
3 months, researchers asked whether the participants remember seeing the video of the
bus blow up ( there was no video). 28% claimed to have seen a video which did not exist.
There is evidence that police officers have great faith in eyewitness evidence. A survey of British
police officers found that, generally speaking, they valued witness evidence positively. The
majority believed that witnesses are usually correct and three quarters thought that they were
never or rarely incorrect. On the other hand, about half felt that witnesses remember less than
the officer needed.
Eyewitness Testimony as a central issue in Forensic and Criminal Psychology
● German psychologist Albert Von Schrenk-Nortzing testified at the Munich trial of a triple
murder. Basing his argument on the then emerging academic research into the nature of
suggestibility and memory, Von Schrenck-Notzing unsuccessfully argued that witnesses
confuse real-life events with events they read about in the press. He used the phrase
‘retroactive memory falsification’.
● Munsterberg, the father of forensic psychology, argued that there was probably no
relationship between the accuracy of an eyewitness and the eyewitness’s confidence in
the accuracy of his or her testimony.
● Eyewitness misidentification is the greatest contributing factor to wrongful convictions
proven by DNA testing, playing a role in more than 70 percent of convictions overturned
through DNA testing nationwide
● The topic remains important in terms of justice. According to the Innocence Project
(2017), eyewitness misidentification played a role in over 70 per cent of proven (DNA
exonerated) cases now known.
● Example: The case of Ronald Cotton- Cotton spent 10 yrs in jail for a rape actually
committed by another man. There was little evidence against him. One victim identified
him from the photographic line up. Eventually, the DNA evidence from semen left by the
actual rapist led to his release.
Accuracy of Eyewitness Evidence
Case of Anna Lindh, the swedish foreign minister. She was stabbed several times by a lone
attacker when visiting a department store. The attack lasted less than 15 seconds before the killer
escaped the crime scene. There were 29 witnesses to the stabbing, mainly women. Each one was
interviewed up to five times by the police. Descriptions of the offender provided by the witnesses
were the main data for the study. One notable event in the course of the study was that the police
released pictures of the suspect three days after the killing – some witnesses were interviewed
both before and after the release of pictures. The availability of CCTV video of the offender a
few minutes before the attack provided the baseline information of the offender characteristics
for the researchers.
The main findings were that, in this case, the accuracy of the witnesses was not good. Only 35
percent of the details provided were correct, with a further 24 per cent only partly correct. This
left a high percentage of details which were actually misleading or potentially misleading in the
investigation.
Later Intrusions in the Memory
The early studies of human memory in the first part of the twentieth century largely consisted of
the memorising of nonsense syllables following the work of Ebbinghaus (1913): hardly a
situation conducive to the study of eye-witness testimony.
Neisser (1982) and Neisser and Winograd (1988) published seminal work on human memory in
real-life contexts. Consequently, from the 1970s onwards, academic memory researchers carried
out numerous studies of eyewitness memory.
Work of Elizabeth Loftus- the most famous of her studies were demonstrations that subsequent
events influenced testimony about incidents. Witnesses to a robbery or accident may be exposed
later to new information – perhaps during a police interview, for example. In some circum-
stances, that new information can influence how they recollect the incident. Furthermore,
information in one modality may affect memory for events held in a different modality. Thus
verbal information may affect visual recall.
● Retrieval inhibition- Recall of a crime scene may also be altered depending on how the
eyewitness is initially questioned
● Cross racial identification- when we observe someone of our own race, we tend to
classify their facial features in greater detail. In contrast, we may encode the features of
people from other races more superficially, paying less attention to facial characteristics
such as shape of face, skin tone, size of features, and hair texture
● Stress and weapons focus- If eyewitnesses see the perpetrator holding a gun or a knife,
their ability to recognize the assailant is impaired. If people are in low stress condition,
they are 71% likely to make correct identification. This was done on soldiers in case they
were taken as prisoners of war.
● Unconscious transference- when the person wrongly identifies someone seen near the
scene of crime as the part of identification process.
● Children as eyewitness- children provide less and somewhat less accurate information
when responding to interview questions about what they witnessed. They are about as
accurate as adults when presented with lineups and photospreads, but only if the true
perpetrator is present. If the perpetrator is absent, they do more poorly. Memories of
children are negatively impacted by a stress inducing interview style.
● Pre-existing expectations- Scripts are widely held beliefs about sequences of actions
that typically occur in particular situations.
USE OF LINEUPS AND PHOTO ARRAYS
In case of a lineup, the suspect is shown to the witness live along with foils/fillers in person
through a one-way mirror. Can also be asked to speak/make movements. These foils/fillers bear
close resemblance to the suspect and are innocent individuals.
In photo arrays, the witness is not seeing the suspect and foils live and is seeing the images
instead. Foils/fillers are added in images.
Advantages of photo arrays over line ups
● Immediate availability and selection of foils
● Control over the behaviour of lineup members. (possibility to act in a way n live lineup
which catches the witnesses’ attention)
● Portability
● Opportunity to examine a photo array repeatedly and over an extended length of time.
● Less eyewitness anxiety when they use a mug book, in contrast to viewing their potential
attacker through a one-way looking glass.
Video taking lineups- Has advantages not present in either live lineups or photo spreads. can be
paused on a specific frame show in a lineup member in a specific body position; can be shown
repeatedly and for an unlimited amount of time. Through the use of large monitors, faces can be
blown up larger than life. These can also be paused on a specific frame showing a lineup member
in a specific body position; can be shown repeatedly and for an unlimited amount of time.
Show up- basically a line up with only one person.
Common errors made
● Implying that the criminal is definitely one of the stimulus people.
● Pressuring the witness to make a choice
● Asking the eyewitness specifically about the suspect while not asking those same
questions about the foils
● Encouraging a loose recognition threshold in the eyewitness by asking the witness if
there is “anyone familiar,” or “anyone who looks like the person.”
4 rules that can reduce these errors
● “The person who conducts the lineup or photo spread should not be aware of which
member of the lineup or photo spread is the suspect”. It is called a double b;lind
procedure.
● The eyewitness should be told that the perpetrator might not be in the lineup or photo
spread and therefore eyewitnesses should not feel that they must make an identification.
Also, that the administrator does not know who is the perpetrator.
● “The suspect should not stand out in the lineup or photo array as being different from the
distractors based on the eyewitness’s previous description of the culprit or based on other
factors that would draw extra attention to the suspect”
● “A clear statement should be taken from the eyewitness at the time of the identification
and prior to any feedback as to his or her confidence that the identified person is the
actual culprit”
Ways to improve accuracy info elicited from the witness
● Slow down the rate of questioning
● Recreate the original context
● Tailor questions to the individual witness
● Make the interview witness-centered rather than interviewer centered
● Be sensitive to the distinction b/w correct and incorrect responses.
● Be sensitive to temptations to form premature conclusions
EYEWITNESS EVIDENCE IN COURT
Communication Persuasion Approach
Eyewitness testimony is aptly described as persuasive communication – an appeal to an audience
(for example, a jury) to believe one's account of an event. The witness, in essence, is an influence
agent delivering what we might call a "memory message." The fact finding audience, in its turn,
decides whether or not to accept, or be persuaded by, the message, just as would the audience to,
say, a speech concerning some socio political issue. Persuasion researchers have found that a
number of factors may influence acceptance of a message:
● Both source or communicator characteristics
1. Attractiveness
2. expertise
● Audience characteristics
1. preexisting attitudes
2. Knowledge about the message topic, may contribute to the persuasive impact of
the message
● Logic and strength of message arguments
1. especially if the audience is highly motivated to hold an informed opinion on the
issue
● Delivery style of the communicator may contribute to persuasive impact.
1. Fast speech rate
2. Steady eye contact, may increase a speaker’s persuasiveness
Model of Eyewitness Persuasion
The major influences are what the witness says (message content) and how he or she says it
(message delivery style). The memory report, both style and substance, is influenced by at least
three other sets of variables, which, via their effects on the memory report, have indirect
influences on fact finder judgments. A police officer or lawyer may question the witness, and
that questioning may influence both the content and delivery style of the report.Finally, the
memory report may be influenced by static attributes of the witness, such as his or her age and
status. Witness attributes affect memory reports because they are correlated with memory and
communication abilities and motivation. A third set of direct influences on fact finder appraisals
includes the fact finders‘ preexisting beliefs, biases, and stereotypes about eyewitness memory.
The fourth category of direct influences on fact finder appraisals is knowledge of witnessing
conditions. Jurors (typically) and police interviewers (often) may have information about the
memory event gained independently of the witness. They can be expected to enter this
information into their calculation of how accurate the witness's report is.
Determinants of memory believability
● Jurors and other fact finders: Studies suggest that people over believe memory reports.
Fact finders do not extend their optimistic expectations to all eyewitnesses
indiscriminately. They believe children under nine or ten years of age typically have
poorer memories and are more suggestible than adults. Elderly people appear from some
research to have low credibility as memory sources. On the other hand, people may tend
to believe that police officers are highly competent witnesses, presumably because of
their training and experience.
● Witness attributes and the message: Witnesses with various static and ascribed
qualities may communicate in ways that make them look less or more accurate. Police
officers may convey a compelling sense of certainty. Young children may have trouble
communicating their memories in a logically sequential or internally consistent fashion ,
and may be less accurate in some cases than are adult witnesses. And people from lower
status backgrounds are more likely than more socially privileged individuals to emit
negative credibility cues in their speech.
● Content of the report: Details- Factfinders seem more impressed with eyewitnesses
who provide a lot of details in their testimony, whether the details are about surrounding
context or simply vividly depict the central focus of attention.
1. Verbal confidence- real memories were expressed more confidently than
suggested memories. This is consistent with a reality monitoring account in that
the memory for something actually seen should be stronger or more vivid to the
individual. Thus, verbal assertions of confidence represent a message content that
should signal to fact finders that the eyewitness is experiencing a strong
recollection.
2. Admission of memory failure: In an interview, or during courtroom
examination, the eyewitness who answers "I don't know" to a high percentage of
the questions is apt to look bereft of memory. Research, described earlier, the
negative impression may be a global one - generalizing into heightened
skepticism about affirmative answers to other questions.
3. Consistency- If, within a single memory report, the witness makes contradictory
statements, most fact finders will take notice. Especially in the absence of a
challenging questioner, glaring inconsistencies in the same report are highly
unlikely and thus unexpected.
4. Signal-to-noise-ratio: This is related to the reality monitoring notion that
imagined or internally generated memories are more likely to include mention of
cognitive processes, descriptions of what the witness recalls "thinking or paying
attention to" while viewing or remembering the event.
5. Confidence
6. Powerfulness of speech: There is a difference between the speech of high SES
people and low SES people. High SES people use stylistic terms, speak
powerfully and avoid hedges.
● Questioning factors: shaping memory messages by inquiry.
1. Repeated questioning: repeated offering of a memory report may lead to
increased commitment to and confidence in that report.
2. Biased lineup instructions and forced choices: Eyewitnesses are less likely to
reject a lineup under biased lineup instructions, that is, when the administering
law officer presents the lineup with verbal assertions that the perpetrator is in the
lineup and without explicitly offering a "none of the above" option.
3. Eliciting memory failure admissions: The flip side of this is the questioning
style that seeks to get the witness to admit, as much as possible, to not knowing or
not remembering. This strategy may be pursued at trial by the crossexamining
attorney.
4. Creating fragmentation: The general practice is for attorneys to allow their own
witnesses to talk at some length and so display a narrative style, but try to induce
a fragmented style in opposing witnesses.
5. Cross-examination shake up: cross-examination can influence both the
substance and style of a memory report. Skilled lawyers can highlight
inconsistencies as well as use verbal trickery to lead the eyewitness to make
statements that appear inconsistent. Perhaps the most likely effect of
cross-examination is to make the witness appear less confident.
6. The power of suggested consensus: It is not unusual for more than one person to
witness the same crime. This introduces a potential for the testimony of one
witness to influence the questioning of a second witness. Based on what the first
witness reports, a police officer may form a theory of what happened, making
certain inferences about what "must have been." Consciously or unconsciously,
the police officer may communicate these inferences as facts while questioning
the second witness. The second witness may incorporate these into his or her own
memory.
7. Who is asking: whether the witness is facing supportive direct examination or
tricky cross-examination.
8. Interviewing techniques: Memory interviews should begin with a free recall,
narrative report prompted by an open-ended request. This format creates a
memory report that includes (in the narrative) what is most salient and memorable
to the witness, as well as details.
● Witnessing conditions, memory messages and perceived accuracy: The condition of
the witness during questioning, such as his or her stress or emotional level, may also
affect memory. In addition, the witness's emotions while viewing the event might affect
the memory message if those emotions are stirred anew during testimony. Conceivably,
strong emotion during testimony could decrease believability by making the report less
articulate and full of negative credibility cues. If fact finders know that witnessing
conditions were poor, they may be more predisposed to counter argue the report or
selectively look for problems with the testimony. The indirect route is through the
memory message itself. Physical and temporal conditions (for example, light level,
physical distance from the perpetrator, presence of an attention-riveting weapon, duration
of exposure to the perpetrator, pace of action) naturally should be related to the strength
of the memory trace or, more specifically, the ease, clarity, and amount of recall.
.
