Chapter 5: Eyewitness Testimony Flashcards
eyewitness testimony relies on _____
memory
stages of memory
- Encoding: you perceive and pay attention to details in your environment
- Short-term memory: a short-term holding facility with a limited capacity
- Long-term memory: a long-term holding facility with a large capacity
memory retrieval
- Information in long-term memory can be retrieved as needed
- Our memory can change each time we retrieve an event
two types of eyewitness memory retrieval
recall & recognition memory
recall memory
reporting details of a previously witnessed event or person
recognition memory
determining whether a previously seen item or person is the same as what is currently being viewed
how do researchers usually study eyewitness issues
by employing laboratory simulations
laboratory simulations
expose a participant to an event and is later asked to describe what happened and the perpetrator involved. They may also be asked to examine a lineup
independent variables examined in laboratory simulations
estimator & system variables
estimator variables
variables that are present at the time of the crime and cannot be changed
system variables
variables that can be manipulated to increase or decrease eyewitness accuracy
Dependent variables examined in laboratory simulations
- Recall of the event/crime
- Recall of the perpetrator
- Recognition of the perpetrator
Recall of the crime or the perpetrator can be measured by ___
open-ended recall/ free narrative and direct question recall
open-ended recall/free narrative
witnesses are asked to either write or orally state all they remember about the event without the officer or experimenter asking questions
direct question recall
witnesses are asked a series of specific questions about the crime or the perpetrator
A witness’ recall can be examined for ____
- The amount of information reported
- The type of information reported
- The accuracy of the information reported
Recognition of the perpetrator can be measured by ___
lineup
lineup
a set of people presented to the witness, who must state whether the perpetrator is present and, if so, which person it is
A witness’ recognition can be examined for
- Accuracy of decision
- Types of errors made
goal of interviewing eyewitnesses
to extract a complete and accurate report of what happened
Fisher et al., 1987 interviewing eyewitnesses study
analyzed 11 tape-recorded interviews from a police department in Florida and found that officers tended to introduce themselves, ask the eyewitness to report what they remembered in an open-ended format, then ask the witnesses a series of direct questions to determine specific information, and finally, ask eyewitnesses if there was any additional information they could remember
Problems with police officers’ approach to interviewing eyewitnesses
- Police officers often interrupt eyewitnesses, which might prevent them from speaking or distract them
- Police officers used short, specific questions, which were often irrelevant and resulted in short answers
- Police officers tended to ask questions in a random order
- Memory conformity
memory conformity
when what one witness reports influences what another witness reports
the misinformation effect
a phenomenon where a witness who is presented with inaccurate information after an event will incorporate that misinformation into a subsequent recall task
Loftus & Palmer, 1974 the misinformation effect and phrasing of questions study
had participants watch a video of a car accident and estimate the speed of the cars. They found that the participants estimated a higher speed when they used the word smashed, followed by collided, bumped, and contacted. A week later, participants who were questioned with the word smashed were more likely to recall seeing broken glass than other participants
how do researchers study the misinformation effect?
Misinformation studies use a common paradigm, where participants are exposed to an event via slides, video, or life action and are given a series of questions about the event, some of which contain misinformation. They are then asked a series of questions about the event probing into the misinformation
Loftus, 1975 misinformation effect study
found that incorporating the number of demonstrators into the question posed to witnesses affected the number of demonstrators witnesses recalled seeing later
3 main explanations for the misinformation effect
- Misinformation acceptance hypothesis
- Source misattribution hypothesis
- Memory impairment hypothesis
misinformation acceptance hypothesis
the incorrect information is provided because the witness guesses what the officer or experimenter wants the response to be
Source misattribution hypothesis
the witness has two memories: the original and the misinformation. However, the witness cannot remember where each memory originates or the source of each
Memory impairment hypothesis
the original memory is replaced with the new, incorrect information
Ways that witnesses are exposed to misinformation
- A police officer makes assumptions about what occurred and inadvertently phrases a question consistent with that assumption
- The witness overhears another witness’ statement and changes their report to make it consistent
- A police officer may incorporate an erroneous detail from a previous witness’ interview
procedures that help police interview eyewitnesses
- hypnosis
- the cognitive interview
- recall of the perpetrator
hypnotically-refreshed memory
a phenomenon whereby a witness can produce more details than a non-hypnotized witness
2 techniques for eyewitness hypnosis
age regression & television technique
age regression
the witness goes back in time and re-experiences the original event
television technique
the witness imagines they are watching a television screen with the events being played as they were witnessed
efficacy of hypnosis in eyewitness recall
- Studies show that while individuals under hypnosis provide more details, those details are just as likely to be inaccurate as accurate
- Hypnotized individuals are more suggestible to subtle cues by the interviewer
what hypnosis technique might help with recall?
closing one’s eyes
admissibility of hypnotic information in court
Courts do not permit information obtained by hypnosis to be used as evidence
the cognitive interview
an interview procedure for use with eyewitnesses based on the principles of memory and retrieval
four memory retrieval techniques to increase recall
- Reinstating the context
- Reporting everything
- Reversing order
- Changing perspective
efficacy of cognitive interviews
Studies show that cognitive interviews produce the greatest amount of accurate information without an increase in inaccurate details
enhanced cognitive interview
an interview procedure that includes various principles of social dynamics in addition to the memory retrieval principles used in the original interview
Additional components of the enhanced cognitive interview
- rapport building
- supportive interviewer behaviour
- transfer of control
- focused retrieval
- witness-compatible questioning
rapport building
An officer should spend time building rapport with the witness and make them feel comfortable and supported.
supportive interviewer behaviour
A witness’ free recall should not be interrupted; pauses should be waited out by the officer, who should express attention to what the witness is saying.
transfer of control
The witness, not the officer, should control the flow of the interview; the witness is the expert—that is, the witness, not the officer, was the person who saw the crime.
focused retrieval
Questions should be open-ended and not leading or suggestive; after free recall, the officer should use focused memory techniques to facilitate retrieval.
witness-compatible questioning
An officer’s questions should match the witness’ thinking; if the witness is talking about clothing, the officer should be asking about clothing.
efficacy of cognitive interviews vs. enhanced cognitive interviews
There isn’t a statistical difference in the accuracy of the two types of cognitive interviews
why are some officers reluctant to use cognitive interviewing?
because it requires a lot of training and time, and the use of an appropriate environment
accuracy of perpetrator descriptions
- Perpetrator descriptions provided by witnesses tend to be limited in detail and accuracy
- Hair colour, hairstyle, and gender tend to be reported most accurately, while eye colour and weight tend to be reported least accurately
staged crimes and perpetrator recall
Witnesses of staged crimes report more descriptors of the perpetrator than witnesses of real crimes
written vs. oral statements and perpetrator recall
Asking witnesses to write out descriptions produced shorter and less accurate descriptions than when witnesses orally stated their descriptions
A witness’ recognition memory can be tested by
- Live lineups or photo arrays
- Video surveillance records
- Voice identification
suspect
A person the police “suspect” committed the crime, who may be guilty or innocent of the crime in question
perpetrator
The guilty person who committed the crime
impact of lineup identifiaction
it reduces the uncertainty of whether a suspect is the perpetrator beyond the verbal description provided
foils/distractions
Lineup members who are known to be innocent of the crime in question
similarity-to-suspect strategy
- matches lineup members to the suspect’s appearance
- makes it difficult to identify the perpetrator
match-to-description strategy
distractors are matched only on the items that the witness provided in their description
fair lineup
A lineup where the suspect does not stand out from the other lineup members
how should we avoid a biased lineup?
if a feature is provided in the witness’ description but does not match the subject’s appearance, the distractors should match the suspect’s appearance on that feature
target-present lineup
A lineup that contains the perpetrator
target-absent lineup
A lineup that does not contain the perpetrator but rather an innocent suspect
possible identification decisions of a target-present lineup
- correct identification
- false rejection
- foil identification
possible identification decisions of a target-absent lineup
- foil identification
- correct rejection
- false identification
correct decision in a target-present lineup
to make a correct identification
correct decision in a target-absent lineup
to make a correct rejection
foil identification
a known error to police, so the person involved will not be prosecuted
false rejection
an unknown error that may result in the guilty suspect going free
false identification
an unknown error that may result in the innocent suspect being prosecuted
photo array
photographic lineups
why are photo arrays used more often than live lineups?
- They are less time-consuming to construct
- They are portable
- The suspect doesn’t have the right to counsel
- The police don’t need to worry about the suspect’s behaviour drawing attention
- They might make a witness less anxious
benefit of video lineups
they allow witnesses to enlarge faces and focus on particular features
identification and rejection rates of live vs. video-recorded lineups
- Correct identification and rejection rates don’t differ across live and video-recorded lineups
- For adolescents, video lineups have a slight advantage for correct rejections
impact of passing through the lineup more than once on accuracy
Witnesses asking for additional passes through the lineup are more likely to guess, especially with foil identifications
use of standards and perpetrator recall
The use of a standard does not help witnesses recall accurate information about a perpetrator
simultaneous lineup
a common lineup procedure that presents all lineup members at one time to the witness
what type of judgment is used in simultaneous lineups?
relative judgment
relative judgment
the witness compares lineup members to one another and the person who looks most like the perpetrator is identified
sequential lineup
Alternative lineup procedure where the lineup members are presented serially to the witness, and the witness must decide whether the lineup member is the perpetrator before seeing another member. Also, a witness cannot ask to see previously seen photos and is unaware of the number of photos to be shown
what type of judgment is used in a sequential lineup?
absolute judgment
absolute judgment
The witness compares each lineup member to their memory of the perpetrator to decide whether the lineup member is the perpetrator
Lindsay & Wells, 1985 accuracy and lineup type
- The study compared the identification accuracy rate achieved with the simultaneous and sequential lineup procedures. They found that correct identification rates did not differ across lineup procedures. However, correct rejection rates were significantly higher with a sequential lineup
- Some researchers argue that the simultaneous and sequential lineups produce similar rejection rates
Megreya et al., 2012 eye movements and lineup identification study
examined the eye movements of witnesses examining a lineup. Faces that were on the left side were looked at first and were more likely to be incorrectly identified as the target
showup
an identification procedure that shows one person to the witness: the suspect
problems with a showup
Researchers and courts have argued that in a showup, the witness is aware of who the police suspect is, which may increase their likelihood of making a false identification
Gonzalez et al., 1993 witness rejection in showups study
found that witnesses were more likely to reject a showup than all members of a lineup
Yarmey et al., 1996 false identification in showups study
found that lineups produced lower false-identification rates than showups
Steblay et al., 2003 false identification in showups meta-analysis
conducted a meta-analysis and found that false identifications were higher with showups than lineups
identification in field vs. photographic showups
- Suspects are more likely to be identified in a field showup than in a photographic lineup
- Consistent with the notion that showups are suggestive
Wetmore et al., 2015 accuracy of showups study
showed participants a crime video followed by a showup or simultaneous lineup. Showups never resulted in higher accuracy, even when lineups were biased
Two acceptable uses of a showup
- Death-bed identification
- If a suspect is apprehended immediately at or near the crime scene
walk-by
identification procedure that occurs in a naturalistic environment. The police take the witness to a public location where the suspect is likely to be. Once the suspect is in view, the witness is asked whether they see the perpetrator
biased lineup
a lineup that suggests whom the police suspect and thereby whom the witness should identify
3 main types of biases increase false positives
- foil bias
- clothing bias
- instruction bias
foil bias
the suspect is the only lineup member who matches the description of the perpetrator
clothing bias
the suspect is the only lineup member wearing clothing similar to that worn by the perpetrator
instruction bias
the police fail to mention to the witness that the perpetrator may not be present
Charles Lindbergh case
Lindbergh identified Bruno Hauptmann as the suspect who kidnapped his infant son by voice identification. He recognized Hauptmann’s voice as the one he heard 3 years earlier when he paid the ransom
Orchard & Yarmey, 1995 mock kidnapping and voice identification study
Had university students listen to a taped video of a mock kidnapped and found that:
1. Identification accuracy was higher with longer voice samples
2. Whispering significantly decreased identification accuracy
3. Distinctiveness interacted with whispering, influencing identification accuracy
Oham et al., 2011 voice identification lineup study
exposed participants to a 40-second recording of an unfamiliar voice. 2 weeks later, they were presented with a seven-voice lineup, either target-present or target-absent. All conditions resulted in poor performance. The only condition in which participants performed better was the target-present condition with 11-13-year-olds
Philippon et al., 2013 laughter identification study
investigated whether laughter would influence the accuracy of voice identification. They found that participants were no more likely to recognize a voice when it was accompanied by laughter or only the laughter was heard. When the target was absent, laughter with speech resulted in higher accuracy while in target-present situations, laughter alone resulted in more correct identifications
impact of whispering on voice identification
The likelihood of a correct identification is decreased if a voice is changed by whispering or muffling, or through emotion
impact of placement in a lineup on voice identification
If the target voice occurs later in the lineup, correct identification decreases compared with an earlier presentation
impact of unfamiliar accents on voice identification
Participants are more accurate at voice identification when the speaker had a familiar vs. a different accent
Pickel & Staller, 2012 detail and voice identification study
examined how a voice with an accent affected how witnesses described the perpetrator’s appearance. Witnesses viewing a perpetrator who spoke with an accent reported less developed physical descriptions of the perpetrator and were less accurate in identifying the voice. If the message spoken was more vs. less detailed, the witnesses provided fewer accurate details about what the perpetrator looked like. Increasing the threatening nature of the message led to more inaccurate descriptions of the perpetrator’s appearance
Cook and Wilding, 1997 face and voice identification study
when the target’s face was visible when participants originally heard the voice at encoding, correct identification decreases greatly
impact of the size of the lineup on voice identification
as the number of foils increased from 4 to 8 voices, correct identification decreased
are several identifications better than one?
Pryke et al., 2004 found that exposing witnesses to more than one lineup, each consisting of a different aspect of the suspect, increased the ability to determine the reliability of an eyewitness’ identification of the suspect
Neil v. Biggers
the U.S. Supreme Court ruled that the confidence of a witness should be taken as an indicator of accuracy
overall impact of confidence on witness accuracy
There is a small positive correlation between accuracy and confidence, but there are many moderator variables that can increase or decrease this relation
moderator variables of the confidence-accuracy relationship
- Confidence has a particularly strong relationship with accuracy when the decision is made very quickly
- When confidence is assessed at the time of initial identification, there is a strong relationship between confidence and accuracy
- There is no relationship between confidence and accuracy when a “not here” decision is made
- Post-identification feedback increases confidence and thereby affects the confidence-accuracy relationship
- The more often you express a decision, the more your confidence increases and thereby affects the confidence-accuracy relationship
Odinot et al., 2013 length of intervals and confidence study
found that a longer interval between viewing the video of a complex situation and answering questions about it was only associated with decreased confidence for incorrect answers, not correct answers
Wright & Skagerberg, 2007 confidence and ratings of task difficulty study
found that eyewitnesses to actual crimes reported identifying the suspect as a more challenging task if they did not correctly identify the suspect
Wells et al, 1998 on confidence in suspect identification
argue that police should ask witnesses for their confidence ratings immediately following their identification decision and before any feedback and that this rating should be used in court
age as an estimator variable
- Older adults make fewer correct identifications and fewer correct rejections than younger adults regardless of the type of lineup
- Correct identification and correct rejection increases until older adulthood
- Younger adults make more correct rejections when the perpetrator is also a young adult
cross-race effect
the phenomenon of witnesses remembering their race faces with greater accuracy than faces from other races
identification of own-race faces
Own-race faces produce higher correct identifications and lower false positives than other-race faces
how does the cross-race effect impact one’s likelihood of making a selection in a lineup?
Both white and Indigenous people are more likely to make a selection when trying to identify a cross-race face
do intoxicated participants display the cross-race effect?
Being intoxicated had a larger negative effect when recognizing same-race faces compared to other-race faces
three common explanations for the cross-race effec
- attitude
- physiognomic homogeneity
- interracial contact
attitudes
people with fewer prejudicial attitudes may be more inclined to distinguish among members of other races
does research support the attitudes hypothesis?
- Research does not support this explanation
- Having prejudicial attitudes may be related to intergroup contact, which may help to explain the other-race effect
Physiognomic homogeneity
suggests that some races have less variability in their faces
does research support the physiognomic homogeneity hypothesis?
- Research does not support this explanation
- Some physical features may be more appropriate for discriminating across faces of certain races, and thus, people from other races may not pay attention to relevant features
interracial contact
the more contact you have with other races, the better you will be able to identify them
does research support the interracial contact hypothesis?
Some support for this hypothesis has been found, but further research is needed
weapon focus
a term used to describe the phenomenon of a witness’ attention being focused on the perpetrator’s weapon rather than on the perpetrator
two primary explanations for weapon focus
- the cue utilization hypothesis
- unusualness
the cue utilization hypothesis
suggests that when emotional arousal increases, attentional capacity decreases
who proposed the cue utilization hypothesis?
Easterbrook, 1959
does research support the cue utilization hypothesis?
There is limited support for this hypothesis
unusualness
- Argues that weapons are unusual and thus attract a witness’ attention, preventing them from encoding other details
- According to this theory, other objects might produce a weapon-focus effect
Pickel, 1999 weapon focus study
found that participants provided less accurate descriptions of a man if he was carrying a gun in the parking lot rather than at a shooting range. The degree of the threat did not influence the descriptions of the man
Carlson & Carlson, 2012 weapon focus and facial features study
found that weapon focus decreased if the perpetrator had a distinctive facial feature
can training decrease weapon focus?
yes, participants can be trained to not focus on a weapon, reducing the weapon-focus effect
meta-analysis findings of the weapon focus effect
Meta-analyses show that the weapon focus occurs in lab and real-world investigations. It can be influenced by the retention interval, exposure duration, and threat. Expert testimony may be useful to jurors to understand the weapon focus effect and the factors that influence it
expert testimony on eyewitness issues controversy
Not all eyewitness experts agree as to whether there is sufficient reliability across eyewitness studies
what aspects of eyewitness issues do researchers feel are reliable enough to have expert testimony presented in court?
- lineup procedures
- interview procedures
- the confidence-accuracy relationship
Ebbsen & Konecni, 1997 on expert testimony on eyewitness issues
argued that eyewitness experts are overconfident in their conclusions and outlined 3 weaknesses in eyewitness research that should limit its usefulness to real-world application and expert testifying
Ebbsen & Konecni’s 3 weakenesses of eyewitness testimony
- Studies examining the same issue produce different results
- Most of the studies use university students; real-life witnesses vary in age and other demographic variables
- Most studies allow a witness to view the perpetrator for approximately 6 seconds; in reality, witnesses may view the perpetrator for 5+ minutes
Leippe’s arguments in support of eyewitness research
- Eyewitness research uses many methodologies and types of participants
- Many studies are highly reliable
studies on the public’s knowledge of eyewitness issues
Many studies have suggested that the public may not be sufficiently knowledge about eyewitness issues to evaluate this evidence in court
expert testimony on witnesses in the CJS
The Canadian justice system limits the testimony of eyewitness experts on issues in court
R. v. McIntosh and McCarthy (1997)
the Ontario Court of Appeal ruled not to permit expert testimony on eyewitness identification issues
R. v. Henderson (2009)
a Manitoba judge allowed a jury to hear expert testimony on the limitations of eyewitness identification in a murder case
eyewitness identification and DNA exoneration
In more than 75% of DNA exoneration cases, the primary evidence used to convict was eyewitness identification
innocence Canada
- A project of pro bono lawyers who have been working to free wrongfully convicted people in Canada since 1993
- Innocence Canada has freed over 22 innocent individuals since its founding, who served more than 190 years combined in prison for crimes they did not commit
Wells et al.’s 4 guidelines for eyewitness evidence
- The person who conducts the lineup or photo array should not know which person is the suspect
- Eyewitnesses should be told explicitly that the criminal may not be present in the lineup, and therefore, witnesses should not feel that they must make an identification
- The suspect should not stand out in the lineup as being different from the foils based on the eyewitnesses’ previous description of the criminal or based on other factors that would draw extra attention to the suspect
- A clear statement should be taken from the eyewitnesses at the time of the identification and before any feedback as to their confidence that the identified person is the actual criminal
Kassin’s additional rule for lineup identification
the entire lineup procedure should be recorded on video to ensure accuracy in the process, particularly the interactions between the officer and the witness
Prof. Neil Brooks
prepared 38 Canadian guidelines titled Police Guidelines: Pretrial Eyewitness Identification Procedures, but they are not always followed
Supreme Court Justice Peter Cory
made 43 recommendations for eyewitness testimony in light of the R. v. Sophonow, 1986 case
4 of Peter Cory’s key recommendations
- The photo lineup procedure with the witness should be videotaped or audiotaped from the point the officer greets the witness to the completion of the interview
- Officers should inform witnesses that it is just as important to clear innocent suspects as it is to identify guilty suspects
- The photo lineup should be presented sequentially
- Officers should not discuss a witness’ identification decision with them
