Eyewitness Testimony

Question 1

What study shows how leading questions can influence eye witness testimony?

Answer 1

• Loftus & Palmer (1974)
• Participants shown a video of two cars colliding, then asked to give a speed estimate
• Higher estimate given when question uses word ‘crash’ rather than ‘hit’

Question 2

What are the two explanations for how leading questions can influence eye witness testimony?

Answer 2

• Response bias explanation: question affects the given answer, but not the actual memory
• Substitution explanation: question influences/distorts the memory

Question 3

How is the substitution explanation for leading questions influencing memory limited?

Answer 3

EWT is more accurate for central details and resists influence, so some memory remains undistorted

Question 4

What is post-event discussion?

Answer 4

When witnesses hear details from other accounts of the same event and they incorporate those details into their own account

Question 5

What are the two explanations for how post-event discussion can influence eye witness testimony?

Answer 5

• Memory contamination: information from own memory and heard account are combined, distorting the original memory
• Memory conformity: Details from heard account deliberately added due to normative or informational social influence

Question 6

What explanation for how post-event discussion can influence memory is more likely and why?

Answer 6

EWT often reports a mid-ground between their own memory and a heard account, which suggests contamination over conformity

Question 7

What study supports the theory that anxiety has a negative effect on recall in EWT?

Answer 7

• Johnson & Scott (1976)
• Participants either heard a conversation in another room and saw a man holding a pen walk out, or an argument and saw a man holding a bloody knife
• Were then to identify the man from 50 photos; man with pen showed 49% accuracy while man with knife had 33%
• This is because of weapon focus

Question 8

What are the strengths and limitations of the theory that anxiety has a negative effect on recall in EWT?

Answer 8

• Johnson & Scott (1976) might have tested unusualness of the object rather than anxiety
• Valentine & Meson (2009) recorded anxiety and recall of those in the Labyrinth of Horror, higher anxiety showed poorer recognition of actors

Question 9

What study supports the theory that anxiety has a positive effect on recall in EWT?

Answer 9

• Yuille & Cutshall (1986), interviewed witnesses of a real shooting, higher anxiety showed higher recall of the event
• Fight of flight increases alertness so improves memory

Question 10

What are the strengths and limitations of the theory that anxiety has a positive effect on recall in EWT?

Answer 10

• Yuille & Cutshall (1986) interviews took place 4-15 months after shooting, no control over confounding variables
• Real victims of crime have more accurate recall the more directly they’re involved (higher anxiety)

Question 11

What can explain the contradiction of anxiety having both a positive and negative effect on recall?

Answer 11

• Yerkes-Dodson Law (1908)
• Low and high anxiety both produce low recall, so there’s an optimum point of anxiety to maximise recall

Question 12

Explain the elements of Fisher & Geiselman’s (1992) Cognitive Interview

Answer 12

• Report everything, including irrelevant/unconfident details (may trigger other memories)
• Reinstate context, i.e. environment and emotions (prevent dependant forgetting)
• Explain events in reverse order; prevents dishonesty and the influence of schemas
• Change mental perspective to the perpetrator’s or another witness’s; prevents influence of schemas

Question 13

What additional elements are added in the enhanced cognitive interview?

Answer 13

Social dynamics: time is spent reducing witness’s anxiety and distractions, are encouraged to speak slowly and are given open-ended questions

Question 14

What research supports the effectiveness of the cognitive interview?

Answer 14

• Köhnken et al. (1999) meta-analysis of studies comparing CI to standard police interviews
• CI showed a 41% increase in amount of accurate information recalled

Question 15

What are the limitations of the effectiveness of the cognitive interview?

Answer 15

• CI results in increase of accurate and inaccurate information reported (encourages quantity over quality)
• ‘Report everything’ and ‘reinstate context’ produce better recall than other elements, so some aspects more useful than others
• CI takes time and training that most police forces can’t provide