How Accurately Can Laypersons Predict Factors That Affect Eyewitness Testimony?

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How Accurately Can Laypersons Predict Factors
That Affect Eyewitness Testimony?
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Instructions

• For this experiment, Im going to give you
  descriptions of specific experimental conditions
  from an eyewitness study that was done in
  Victoria.
• The descriptions on the slides are the same as
  the descriptions on the handouts.

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Instructions

• After the description of each scenario, there are
  a few questions for you to answer.
• Do not read ahead. Each scenario only takes one
  page.
• If you have any questions, please ask the
  experimenter.

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The Original Experiment

• A few years ago, 287 retail store clerks in
  Victoria were recruited to participate in a study
  to test their memory for customers. About once a
  week, they were to receive a phone call from a
  research assistant and would be asked questions
  about memorable customers of the day. They were
  told that a research assistant for the study
  would come down to the clerks store and explain
  the procedures more thoroughly before the phone
  calls began.
• Two weeks after this first meeting, the store
  clerks were asked to identify the research
  assistant they had met from an 8-person photo
  lineup like those used by the police. There is an
  example of a photo lineup on the next slide.

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Lineup Example
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The Original Experiment

• The store clerks tested were intended to be
  representative of store clerks in Victoria.
• 92 of the clerks were men and 193 were women. 2
  clerks did not provide information about their
  gender.
• The clerks had worked in retail between 1 and 33
  years, with an average of 6.7 years.

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The Original Experiment

• To begin the experiment, a female, Caucasian
  research assistant in her early 20s arrived at
  the store to give instructions for the study and
  to complete demographic questionnaires and
  informed consent forms. This meeting lasted about
  10 minutes. Halfway through the meeting, fifty
  percent of the clerks were warned that at some
  point in the future they might be asked to give a
  physical description of the research assistant
  and identify her from a photo lineup like those
  used by the police. They were not told when this
  identification might occur. The other fifty
  percent of the clerks were told nothing about
  possibly being asked to describe and identify the
  research assistant.

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The Original Experiment
Julie, the Research Assistant
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The Original Experiment

• Two weeks after the meeting, a male research
  assistant arrived at the store and asked the
  clerks to complete two 8-person photo lineups.
  The clerks were not told whether the lineups they
  were seeing contained a picture of Julie the
  research assistant or not. They had the option to
  indicate that Julie was not shown in the lineup.
  The photos in each lineup were of people who were
  similar in terms of gender, age, height, build,
  and hair colour.

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The Original Experiment

• First, they were shown a lineup that did not
  have a picture of Julie, similar to a situation
  in which the police are pursuing an innocent
  suspect. The researchers wanted to determine how
  many of the clerks might falsely identify someone
  from a first lineup. The clerks were not given
  any feedback about how they had done on their
  identification. Afterward, they were shown a new
  lineup with all different photos that did have a
  picture of Julie.

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The Original Experiment

• After each identification, the clerks were asked
  to rate their confidence in that decision on a
  5-point scale, exactly like the one shown here
• Not at all sure Very sure
• 1 2 3 4 5

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This Experiment

• Next are some descriptions of specific parts of
  experimental situations that clerks experienced
  as part of this research study. After the
  descriptions are some questions that ask you to
  give your best estimate about the results.
  Imagine that you are a juror in a trial,
  evaluating the testimony of a witness who made an
  identification under these types of
  circumstances. Please read the scenarios and
  questions carefully. When you have finished
  answering the questions from a scenario, put the
  completed page into the envelope before moving on
  to the next page.

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Scenario 1-A

• Clerks were told that they were going to
  participate in a research study about store
  clerks memory for customers. Halfway through the
  first meeting with Julie, the clerks were warned
  that they might later be asked to identify her.
  Two weeks later, a male research assistant
  administered an 8-person lineup in which Julie
  was not present. The clerks were told that a
  photo of Julie may or may not be included in the
  eight photos. If the clerk believed that Julie
  was present, they were asked to give the number
  associated with her photo. If they believed she
  was not present, they were told to say not
  present. After they made a decision, they rated
  their confidence in that decision on the 5-point
  scale.

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Scenario 1-A

• Key Points Warned they might later have to
  identify Julie, two week delay before
  identification, 8-person lineup with no photo of
  Julie.

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The Lineups

• The next slide shows a lineup that the clerks
  viewed in the study. In this lineup, Julie is
  absent.
• Take your time viewing the lineup. When you are
  ready to go on, press the space bar to continue.

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(No Transcript)
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Scenario 1-A

• Please answer the first page of scenario
  questions now.
• When you are done, put the answer sheet in the
  envelope.

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Scenario 1-B

• After completing the first lineup
  identification, the same clerks were administered
  a second, completely different 8-person lineup in
  which Julie was present. They did not receive
  feedback about the first lineup. Again, the
  clerks were told that a photo of Julie may or may
  not be included in the eight. If the clerk
  believed that Julie was present, they were asked
  to give the number associated with her photo. If
  they believed she was not present, they were told
  to say not present. After they made a decision,
  they rated their confidence in that decision on
  the 5-point scale.

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Scenario 1-B

• Key Points Warned they might later have to
  identify Julie, two week delay before
  identification, 8-person lineup with a photo of
  Julie.

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The Lineups

• The next slide shows a lineup that the clerks
  viewed in the study. In this lineup, Julie is
  present.
• Take your time viewing the lineup. When you are
  ready to go on, press the space bar to continue.

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Julie
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Scenario 1-B

• Please answer the second page of scenario
  questions now.
• When you are done, put the answer sheet in the
  envelope.

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Scenario 2-A

• Clerks were told that they were going to
  participate in a research study about store
  clerks memory for customers. These clerks were
  not warned that they might later be asked to
  identify Julie. Two weeks later, a male research
  assistant administered an 8-person lineup in
  which Julie was not present. The clerks were told
  that a photo of Julie may or may not be included
  in the eight photos. If the clerk believed that
  Julie was present, they were asked to give the
  number associated with her photo. If they
  believed she was not present, they were told to
  say not present. After they made a decision,
  they rated their confidence in that decision on
  the 5-point scale.

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Scenario 2-A

• Key Points Not warned they might later have to
  identify Julie, two week delay before
  identification, 8-person lineup with no photo of
  Julie.

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Scenario 2-A

• Please answer the third page of scenario
  questions now.
• When you are done, put the answer sheet in the
  envelope.

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Scenario 2-B

• After completing the first lineup
  identification, the same clerks were administered
  a second, completely different 8-person lineup in
  which the Julie was present. They did not receive
  feedback about the first lineup. Again, the
  clerks were told that a photo of Julie may or may
  not be included in the eight. If the clerk
  believed that Julie was present, they were asked
  to give the number associated with her photo. If
  they believed she was not present, they were told
  to say not present. After they made a decision,
  they rated their confidence in that decision on
  the 5-point scale.

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Scenario 2-B

• Key Points Not warned they might later have to
  identify Julie, two week delay before
  identification, 8-person lineup with a photo of
  Julie.

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Scenario 2-B

• Please answer the fourth page of scenario
  questions now.
• When you are done, put the answer sheet in the
  envelope.

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• There is one last page of demographic questions
  for you to answer.
• When you are done, please put all of the
  questionnaire sheets in the envelope and hand it
  to the experimenter.
• Thanks!