Chapter 14

Chapter 14

+ Chapter 14 Eyewitness Testimony + Eyewitness Demos Greased Lightning (Grease) http://www.youtube.com/watch?v=wK63eUyk-iM Simons & Levin change blindness door study http://www.youtube.com/watch?v=wK63eUyk-iM + Change Blindness Simons and Levin (1998) Design: A stranger asks unwitting participants for directions After 1015 seconds, people carrying a door pass in front

of the participant, blocking their view During this time the stranger is replaced by a different person Results: About 50% of participants failed to notice the switch! Change blindness: Failing to notice apparently obvious changes in a scene 3 Levin et al. (2002) Change blindness blindness: The unduly optimistic belief that one is very rarely affected by change blindness People underestimate the importance of fixating in order to detect changes

They mistakenly assume that they fully process everything in the periphery, too + Some Factors Reducing the Accuracy of Eyewitness Testimony Eyewitnesses generally are taken off guard by the crime They are often preoccupied with their own thoughts and plans The criminal actions are often brief and swift Criminals take steps to avoid recognition e.g. they wear disguises Eyewitnesses are subject to:

Change blindness Prior expectations Pre/post-event information Overblown confidence Unconscious transference Verbal overshadowing Weapon focus 4 + Expectations Can Distort Memory Hastorf

and Cantril (1954) Design: Dartmouth and Princeton students watched an American football game between the two schools They were asked to detect violations of rules Results: Princeton students detected twice as many violations by Dartmouth than did Dartmouth students 5 + Schemas for Bank Robbery The schema for a bank robber is: male, wearing a disguise and dark clothes, making demands for money, with a getaway car and driver. + Expectations Can Distort Memory Lindholm and Christianson (1998)

Design: Swedish and immigrant students watched a simulated robbery, in which a knife-wielding burglar was either: Swedish blond with light skin An immigrant black hair with brown skin The students were asked to pick the perpetrator from a lineup: Half were Swedish (4); half were immigrants (4) Results: The correct person was identified 30% of the time. Both Swedish and immigrant students were twice as likely to mistakenly select an innocent immigrant as an innocent Swede Conclusion: The overrepresentation of immigrants in Swedish crime statistics likely influenced participants expectations 7 + Schemas Shape and Distort Memory Bartlett (1932) Schemas structure our world knowledge and influence

memory storage/retrieval Eyewitnesses use schematic information to assist in their recall Tuckey and Brewer (2003a;b) Eyewitnesses have better recall for schema-relevant information than for irrelevant information. Eyewitnesses generally interpreted ambiguous information in a way that made it consistent with the schema. Contribute to memory reconstruction: Used to piece together the details of an event in terms of what must have been true

Balaclava wearer was male. 8 + Schema Intrusions Increase with Ambiguous Stimuli Mean correct responses and schemaconsistent intrusions in the ambiguous and unambiguous conditions with cued recall. Data from Tuckey and Brewer (2003b). + Leading Questions Loftus and Palmer (1974) Design: Participants watched a multiplecar accident and described what happened Then answered specific questions:

How fast were the cars going when the cars smashed into/hit/collided with/bumped/contacted each other? After one week, they were asked if they saw broken glass (There wasnt any) 10 Results: Speed estimates depended on the word used in the question Highest for smashed -- 40.8 mph Lowest with contacted -- 31.8 mph When smashed was used, participants were more likely to mistakenly claim they saw broken glass (32% compared to 14% for hit) Conclusion: Memory can be systematically distorted by the way questions are phrased Different schemas may be

activated + Interference and Memory Distortion Retroactive Interference Eakin, Schreiber, and SergentMarshall (2003) Eyewitness memory can be impaired by misleading information presented after they have witnessed the crime. This is an example of retroactive interference Memory is impaired even when eyewitnesses were warned about the presence of misleading information after it had been presented. Example maintenance man repairing a chair steals money and a calculator, hiding it under a screwdriver not a wrench. Proactive Interference Lindsay et al. (2004) Design: Listened to a thematically similar or dissimilar narrative prior to seeing a burglary Results:

Recall errors were more frequent when the prior narrative was similar to the actual event This is an example of proactive interference Conclusion: Eyewitnesses previous experiences can shape what they remember Example school visit to palace vs palace burglary. 11 +Explaining Retroactive Interference Distortion Source Monitoring Framework The Source Monitoring Framework A memory probe activates related traces Including memories from other sources One tries to determine the source, based on the information the memory contains Sometimes source misattributions occur Especially likely when memories from different sources

are similar 12 + A Recent Source Misattribution Hillary Clinton in Sarajevo, 1996 "I remember landing under sniper fire," she said in Washington on Monday. "There was supposed to be some kind of a greeting ceremony at the airport, but instead we just ran with our heads down to get into the vehicles to get to our base." News footage of the event however showed her claims to have been wide of the mark, and reporters who accompanied her stated that there was no sniper fire. Her account was ridiculed by ABC News as "like a scene from Saving Private Ryan". http://www.youtube.com/watch?v=8BfNqhV5hg4 Is this motivated political opportunism or was the original memory distorted by viewing other sources of information? + Explaining Retroactive Interference Overwriting the Original Memories Loftus (1979)

Design: Witnessed a pedestrian accident with a car stopping at either a: Stop sign Yield sign Two days later, participants were asked a leading question, referring to the opposite type of sign to the one they had seen (stop vs yield). Forced-choice recognition test for snapshots from the original scene One photo had a yield sign; the other had a stop sign Results: 7085% selected the sign they were falsely led to believe existed. This happened even when subjects were paid for correct answers to reduce demand characteristics. Conclusion: Information from misleading questions permanently alters the original memory, which is overwritten and destroyed. 14 + Misinformation Effect: Caveats Bekerian and Bowers (1983) Misinformation effects can be eliminated by systematically questioning participants in order -- from

earlier incidents to later ones This suggests that the original memory trace survives. Loftus (1992) revised her view to say that eyewitnesses can come to accept misleading information as time goes by. The original memory need not be overwritten but added. Memory distortions are more common for peripheral/minor details than central details. Heath and Erickson (1998) In real-life criminal investigations, eyewitness memories can be quite robust against misleading questions. Yuille and Cutshall (1986) studied people 5 months after a shooting they witnessed. However, there were only 13 subjects and the extent of misinformation was modest. 15

+ Individual Differences Age Young children and elderly adults (age 60-80) are more susceptible to misleading information. Older adults had 43% false memory compared to 4% for younger adults. Elderly adults tend to be very confident in their false memories compared to younger adults. Older adults are more likely to choose someone from a lineup, even when the culprit is absent. Own Age Bias (Wright & Stroud, 2002): Accuracy of identifying someone is increased when the culprit is about as old as the witness older adults are more accurate for older culprits. Perhaps people focus on features of other people like themselves. Steps to reduce age biases:

Make sure older adults and children arent exposed to misleading information. Ask the elderly detailed questions to help them weed out source misattributions. 16 + Childrens Testimony http://www.youtube.com/watch?v=vVh22znRd2Q + Children as Witnesses 18 Accuracy Are traumatic events more memorable than nontraumatic ones? Not terribly (Cordn et al., 2004): Both are influenced by age, delay, and nature of the event Are children more suggestible than adults? Yes (Ceci, Baker, & Bronfrenbrenner, 1988): Younger children are more biased than are older children by leading

questions: Questions that carry with them an implication as to the correct answer 10- to 12-year-olds are no more suggestible than adults The Effect of Leading Questions + Children as Witnesses Suggestibility Thompson, Clarke-Stewart, and Lepore (1997) found that young childrens responses are largely consistent with the view of their questioner. The responses of 5 to 6-year-olds to questions about potential abuse when questioned by: Neutral interviewers: Are generally accurate Accusatory interviewers: Are biased in favor of guilt Exonerating interviewers: Are biased in favor of innocence Young children continue to reflect the prior influence even when: Questioned by a new, non-suggestive interviewer.

Warned that the previous interviewer may have been mistaken. 19 + Children as Witnesses Suggestibility Young children are suggestible because of their: Social compliance They yield to authority figures They lack social support to stand up for their views Cognitive incompetence They come to believe their distorted reports because of limitations in: Processing Attention Language abilities Inability to source monitor They often confuse real-life and television events. 20 + Children as Witnesses How to Maximize Accuracy

Reduce social compliance Avoid leading questions at any point in the questioning process Garven, Wood, and Malpass (2000) Train effective source monitoring techniques Thierry and Spence (2002) Reinstate the encoding context According to the encoding specificity principle, memory should be maximal when the encoding context and the retrieval context match Priestley, Roberts, and Pipe (1999) Use nonverbal recall techniques Asking children to draw what they remember before asking for a verbal report can elicit idiosyncratic retrieval cues and nonverbal information Gross and Hayne (1999) Children remembered 30% more in the drawing condition, which only increased (without adding errors) at longer delays 21 + Eyewitness Confidence

Jurors tend to be influenced by the witnesss apparent confidence. But confidence is NOT always a good predictor of accuracy Sporer et al. (1995) found that the correlation between confidence and accurate identification is: Nonexistent for people who dont make a positive identification. Moderate (+.4) for people who do make a positive identification. Confidence does, however, predict general knowledge accuracy. Perfect and Hollins (1996) suggest that the difference is due to: Having no reference point for the accuracy of eyewitness events. Having a good idea of whether their general knowledge is more/less accurate than others. Witnesses are often coached to be more confident than they are. They also receive confirming feedback from police investigators. 22 + Eyewitness Confidence Confirmatory Feedback Bradfield, Wells, and Olson (2002) Design: Participants were asked to identify a man they saw in a video from a six-person lineup Confirming feedback condition: Regardless of whether they had picked the right person,

witnesses were given confirmatory feedback: Good, you identified the actual subject Neutral condition: No feedback Results: Confirming feedback increased eyewitnesses confidence more when they were incorrect than when they were correct. The correlation between confidence and accuracy was significantly worse in the confirming feedback condition. 23 + Influence of Anxiety and Violence Effects of anxiety are hard to assess in the laboratory because its unethical to expose participants to extremely stressful conditions. Typical laboratory experiments involve: Presenting a film or a staged incident, in which a crucial event occurs, which is either violent/nonviolent, not actual threat. Common findings: Memory for the central aspects of an incident are enhanced by

the presence of violence. This is called the weapon-focus effect Memory for the peripheral aspects of an incident are reduced by the presence of violence. 24 + Robbery Victims Frequently do not Remember Appearance Details Convenience stores with frequent robberies train their staff to notice appearance details and use aids such as height strips to make this easier. + Influence of Anxiety and Violence Weapon-Focus Effect The presence of a weapon causes eyewitnesses to fail to recall other details.

Probably due to attention being naturally drawn to the weapon at the expense of other aspects of the situation Witnesses are less likely to accurately identify a target when a weapon is involved (Loftus, 1979). 49% vs 33% Participants spend more time looking at weapons than a nonweapon substitute (Loftus, Loftus, & Messo, 1987) In real-life crimes the presence of a weapon: Did not affect the rate of identifying a lineup suspect (Valentine et al., 2003), but we dont know who was actually guilty (accuracy). Did have an effect according to police reports (Tollestrup et al., 1994). 26 + Weapon-Focus Effect Unexpected

Expected Low Threat Gun pointed at ground in a baseball field Gun pointed at ground in a shooting range High Threat Gun pointed at woman in a baseball field Gun pointed at woman in a shooting range Pickel (1999) Proposed two possible reasons why a weapon draws more attention:

It poses a threat It is unexpected Fully crossed threat and expectedness in four videos he showed to participants. Tested memory for the person holding the gun Found that: Expected settings improved the ability to ID Threat did not influence ID 27 From Pickel (1999). + Influence of Anxiety and Stress

Deffenbacher et al.s (2004) meta-analyses revealed that heightened anxiety and stress: Negatively impact eyewitness identification accuracy 54% for low anxiety vs 42% for high anxiety conditions. Reduce the ability of eyewitnesses to remember: Culprit details Crime scene details Actions of central characters 64% low anxiety vs 52% high anxiety 28 + Remembering Faces Prosopagnosia Face blindness A profound inability to recognize faces The ability to make fine discriminations among objects is unimpaired

Commonly results from damage to the fusiform face area of the brain This area responds more to faces than objects in normal people Normal peoples face recognition is poorer than wed think: Bruce et al. (1999) asked participants to match the faces: Copyright American Psychological Association. Reprinted with permission. Results: Only 65% accurate when the correct face was present 35% of participants still picked a face even when the correct face wasnt present Video, in conjunction with the photograph, did not improve recognition

29 + Factors Influencing Face Memory Patterson and Baddeley (1977) Task: Two groups were asked to categorize faces based on either: Physical features (e.g. chin, nose, eyes, type of hair) Psychological features (e.g. honesty, intelligence, liveliness) Results: Participants were better at recognizing faces they earlier categorized on psychological dimensions rather than by physical features. Adding a disguise (or removing one from the categorized face) reduced recognition performance.

Faces seen in three quarter view are more recognizable than faces seen in profile (side view). 30 + Effects of Disguises With a wig and beard, you halve your chances of being recognized as the guilty party. Faces seen in three-quarters view are much more recognizable than faces seen in profile. From Patterson and Baddeley (1977). + Holistic Face Processing Holistic/Global Processing: Processing the overall structure of a face/object, paying little attention to the details.

Farah (1994) suggested that: We process faces holistically. We process objects in a more detailed fashion. Explains why Patterson and Baddeley (1977) found a benefit for psychological categorization. Inverted Faces It is harder to recognize the overall structure of a face when it is inverted, compared to an inverted object. Any difficulty recognizing inverted objects quickly disappears with practice.

Not true for inverted faces. This accounts for the Thatcher Illusion (Thompson, 1980) 32 + Holistic Face Processing The Thatcher Illusion The Thatcher illusion. From Thompson, P. (1980). Margaret Thatcher: A new illusion. Perception, 9, 483484. Copyright Pion Limited. Reproduced with permission.. 33 + Holistic Face Processing The Thatcher Illusion The Thatcher illusion. From Thompson, P. (1980). Margaret Thatcher: A new illusion. Perception, 9, 483484. Copyright Pion Limited. Reproduced with permission..

34 + Unconscious Transference Unconscious Transference: The tendency to misidentify a familiar (but innocent) face as belonging to a culprit Ross et al. (1994) Eyewitnesses were three times more likely to select an innocent bystander from a lineup than a stranger. The effect was eliminated by informing them before the lineup that the bystander was not the culprit. 35 + Verbal Overshadowing Verbal Overshadowing Effect for Faces:

Describing a previously seen face impairs recognition of that face Schooler and Engstler-Schooler (1990). Clare and Lewandowsky (2004) Providing a verbal report of the culprit makes eyewitnesses more reluctant to identify anyone in a subsequent lineup. When forced to pick someone, the effect disappears. Brief verbal descriptions are more likely to produce the effect than detailed verbal descriptions. 36 + Cross-Race Effect 37 People are more accurate in recognizing same- than crossrace faces Expertise Hypothesis

Social-Cognitive Hypothesis We are more experienced distinguishing among same-race faces Thorough processing of faces only occurs for individuals with whom we identify (i.e. our ingroup). Evidence: People with more cross-race experience show smaller crossrace effects Caveat: The effect of expertise is small and fragile (Hugenberg et al., 2007) Cross-race effect is eliminated by asking white participants to closely attend to facial features distinguishing black faces from each other.

Evidence: Shriver et al.s (2008) white, educated participants regarded: White faces in wealthy contexts as ingroup members Both white and black faces in impoverished contexts as outgroups Black faces in wealthy contexts as outgroup members Only ingroup faces were well recognized + Police Lineups Police Lineups: A suspect is present along with nonsuspects with broadly similar characteristics It is essential that the suspect is not obviously different from the other

members. Valentine, Pickering, and Darlings (2003) analysis of 314 real lineups: 40% identified the suspect 20% identified a nonsuspect 40% failed to ID anyone 38 Methods to improve lineups: Warn eyewitnesses that the culprit may not be present in the lineup: Steblay (1997) Reduces mistaken IDs by 42% Only reduces positive IDs by 2% Present members of the lineup sequentially instead of simultaneously

Results in a more stringent criterion: Reduces mistaken IDs by about 50% Also significantly reduces positive IDs + Police Interviews Inadequate Technique More Effective Technique 39 Result Close-ended questioning What color was the car? Open-ended questioning What can you tell me about the car? Generates more complete responses without leading the witness Interrupting the witness Allowing the witness time to

finish responding Doesnt disrupt concentration/retrieval cues Asking questions in a predetermined order Ask relevant follow-up questions Takes account of previous answers + Improving Police Interviews 40 The Cognitive Interview (Geiselman et al., 1985) Retrieval Rule Mental reinstatement of context Encouraging complete reporting (even small details) Attempting to describe the events in several different orders Reporting the incident from different viewpoints

Empirical Basis Goal Encoding Specificity Principle Improve the match between encoding and retrieval contexts Memory traces are complex and contain various features Prompting access to multiple, different cues improves recall + Improving Police Interviews Enhanced Cognitive Interview (Fisher et al., 1987) In addition to the four rules, investigators should: Minimize distractions Induce the subject to speak slowly

Allow for a pause between responses and new questions Use appropriate language for the witness Follow up responses with an interpretive comment Try to reduce eyewitness anxiety Avoid judgmental and personal comments Review the eyewitnesss description of events/people under investigation 41 + Comparing Interview Methods The Cognitive Interview:

Generally produces the most accurate information Caveats: Yields slightly more false information than most people given the standard interview (Kohnken et al., 1999) It is most effective when conducted immediately after the crime It is more valuable for recalling peripheral than central details (Groeger, 1997) It is not yet clear how the individual guidelines of the interview contribute to its effects Hypnosis is controversial, as it increases: Peoples suggestibility The amount of false information reported Based on data in Geiselman et al. (1985). 42 + Laboratory vs. Real-Life Settings In contrast to real-life scenarios, laboratory conditions:

Tend to ask for information from individuals not directly involved in the crime (i.e. not the victims themselves) Are less stressful and anxiety-provoking Provide the eyewitness with only a single, passive perspective They cannot move around or interact with other participants in the event Typically grant witnesses far less time to view the event/people Carry only minimal consequences for inaccurate information or false identifications 43 + The Role of Experts Leippes (1995) review of mock-juror/trial studies

The use of experts in eyewitness testimony during a trial: Makes jurors more skeptical of eyewitness testimony Reduces guilty verdicts Leippe et al. (2004) The presence of expert testimony produced a sizeable reduction in guilty verdicts, regardless of the overall strength of the case Thus, it may make jurors unfairly weight potential pitfalls over otherwise strong evidence. 44 + 45 The Case Against Expert Testimony Ebbesen and Konecni (1997)

Conclusions experts might offer are likely debatable given highly inconsistent evidence. e.g. about equal numbers of studies report that high arousal increases (or decreases) eyewitness accuracy. Most research on eyewitness memory emphasizes situational factors, largely ignoring individual differences. Factors that influence eyewitness memory are interactive; however, they are usually studied in isolation. No empirical data convincingly demonstrates that the testimony of defense experts can actually improve the accuracy of jury decisions. In fact, it is often prejudicial. + The Value of Laboratory Research Lindsay and Harvie (1988)

Slideshows, videos, and live staged events all produce roughly equivalent accuracy rates Ihlebaek et al. (2003) Memory for both live staged and videotaped robberies is: Exaggerated in terms of the duration of the event Largely similar in terms of what was remembered/not remembered Yet, watching a videotaped version of events yields more information e.g. better estimates of robbers age, height, weight, and weapon used Conclusions: Witnesses to real-life events are more inaccurate than those who observe the events under laboratory conditions Memory distortions/inaccuracies in the laboratory provide an underestimate of real-life memory deficiencies Thus, laboratory research can still be relevant 46 + Do Jurors Need Expert Advice? The same factors that are important in the laboratory influence real-life police cases (Tollestrup et al., 1994)

Mock jurors cannot discriminate between accurate and inaccurate witnesses (Leippe, 1995) e.g. exposure duration, weapon focus, and retention interval Inaccurate witnesses are mistakenly judged to be accurate by 40 80% of mock jurors Mock jurors do not adequately moderate their verdicts based on factors influencing eyewitness accuracy, like lighting conditions (Lindsay et al., 1986) 47 + The Case For Expert Testimony Cutler, Penrod, and Dexter (1989) Design: Mock jurors viewed realistic videotaped trial of an armed robbery A witness made an ID of a subject under good or bad conditions Expert advice was either offered or not Good Conditions Bad Conditions

Robber not disguised Robber disguised Weapon was hidden from view Weapon was exposed ID took place 2 days after robbery ID took place 14 days after robbery Lineup instructions not suggestive Suggestive lineup instructions Results: Expert testimony led jurors to better weigh the quality of the ID conditions Conclusion: Jurors not exposed to eyewitness testimony were largely insensitive to the quality of witnessing and ID conditions 48 + The Case For Expert Testimony

Jurors who hear expert testimony make more accurate decisions than those who have not (Cutler & Penrod, 1995). Experts only discuss findings from eyewitness research that are generally agreed to be well established. They are forbidden to discuss the research in relation to the specifics of the case, leaving the jurors to decide what is relevant. While the admission of expert advice isnt perfect, it does generally level the playing field and assist in making jurors reasonably more skeptical of eyewitness testimony. 49

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