Eyewitness testimony

What is a leading question?

It is a question which, because of a certain way it is phrased suggests a certain answer

What is a study that investigates leading questions?

Loftus and Palmer

• Showed 45 students 7 clips of road traffic accidents - lab environment

Pt.1

• Asked them the speed of the car- but phrased the question differently to each group - ‘How fast was the cars going when they… 1. Contacted / 2. Hit / 3. Bumped / 4. Collided / 5. Smashed’

• ‘Contacted’ - 32mph / ‘Smashed’ - 41mph

(IV: the wording of the question) (DV: the estimates of speed given by participants)

Pt.2

• Asked them if there were any broken glass - there wasn’t any

• ‘Did you see any broken glass when the cars… 1. Smashed / 2. Hit’

• ‘Smashed’ - Yes 32% / ‘Hit’ - Yes 14%

What was Loftus’ later study? Describe it and its findings

Another lab experiment showing clips

• Control group - ‘Did you see a broken headlight?’

• Experimental group - ‘Did you see the broke headlight?’

• Twice as many in the experimental group said tat they have seen broken headlights

Why do leading questions affect EWT?

1. Response-bias explanation

• Suggests that the wording of the question has no real effect on the participants’ answer, BUT influences how they decide to answer it

• E.g. when a participant gets a leading question with the word ‘smashed’’, it encourages them to give a higher estimate of the car’s speed

2. Substitution explanation

• Suggests the wording of the leading question actually changes participants’ memory

• E.g. participants who originally heard ‘smashed’ later were more likely to report seeing broken glass then those who heard ‘hit’

What is post-event discussion?

PED occurs when there is more than one witness to an event

• They may discuss what they have seen with co-witnesses

• This may influence the accuracy of each witness’ recall of the event

What do post-event discussion impact EWT?

1. Source monitoring theory

• Memories of the event are genuinely distorted - witness can recall information, but cannot recall where it came from

• Source confusion: unsure wether it was from their own memory or did they heard it from someone else

2. Conformity theory

• Memories of the eyewitness are not genuinely distorted - recall changed only because they go along with the accounts of co-witnesses

• Could be for social approval (NSI), or they believe that other witnesses are right and they are wrong (ISI)

What is a research that investigated PED?

Gabbert et al. (2003) - participants in pairs

• Each participant watched a video of the same crime, but in different POVs

• Both participants discussed before individually completing a recall test

• 71% mistakenly recalled aspects of thee event that they didn’t see in the video, but picked up in discussion

• Control group - no discussion - 0% mistakenly recalls

= Evidence of memory conformity

What is the Yerkes-Dodson law?

It explains the effect of anxiety in EWT

We function best when we are at a moderate level of arousal

Moderate level of arousal = optimum level

What are the 4 studies investigating anxiety and EWT?

• Johnson and Scott (1976)

• Yuille and Cutshall (1986)

• Parker et al. (2006)

• Valentine and Mesout (2009)

What was the Johnson and Scott (1976) study?

• Made participants believe that it was a lab study - then hears argument in the next room

2 conditions:

1. Low anxiety: man carrying greasy pen

2. High anxiety: man carrying bloody knife

• They then had to pick out the man from a set of 50 photos

1. Low anxiety: 49% identified him

2. High anxiety: 33% identified him

= Supports the tunnel theory and weapon focus effect

= Anxiety has a negative effect on recall

What is the tunnel theory?

People have enhanced memory for central events

What was the Yuille and Cutshall (1986) study?

• Real life shooting in a gun shop

• 21 witnesses and 13 took part in the study

• Used 7 point scale of stress

• Compared to the number of details remembered after 4-5 months

• Little change in the amount of accuracy in 5 months - very accurate

• Highest level of stress = more accurate

• Less accurate about the colour of items etc.

= Anxiety has a positive effect on recall

What was the Parker et al. (2006) study?

• Interviewing people who had been affected by the destruction brought by a hurricane in the US in 1992

• Defined anxiety in terms of the amount of damage the participants suffered to their homes

• There is a link between the level of recall and the amount of anxiety experienced

= Anxiety can have a positive or negative effect on recall

What was the Valentine and Mesout (2009) study?

• Real life setting of the Horror Labyrinth at the London Dungeon

• Participants given a questionnaire at the end - self reported anxiety

• They also wore wireless heart monitors

• Asked to describe a person they encountered in the dungeon

2 conditions:

1. High anxiety: recalled the fewest correct details - 17% correctly identified the actor in a line up

2. Low anxiety - 75% correctly identifications

= Having higher anxiety makes recall worse

What is cognitive interview?

Geiselman et al. (1984)

1. Context reinforcement: recall the scene, the weather, what you were thinking and feeling

2. Report everything: report every detail you can, even if they seem irrelevant

3. Recall from a changed perspective: describe the event as if it would have been seen from a different viewpoint

4. Recall in reverse order: describe the event in reverse order

What are the aims of CI?

• Improve the effectiveness of interviewers when questioning witnesses

• Gain greater quantities of and more accurate information

• Apply the results of psychological research which showed that memory is not like a video camera but an active process

• Help avoid miscarriages of justice

What are the other elements are enhanced CI?

Fisher et al. (1987) - introduced other elements

• No distractions

• Active listening

• Open questions

• No interruption

• Use the language of the EW as this is how they have information stored

Explain how CI works

1. Context reinforcement: recalling how you felt and the context enhances recall (cues) - RF

2. Report everything: witness might not realise that some detail are important and details could act as cues to help them recall significant information - RF

3. Recall from a changed perspective: encourages many retrieval paths and prevents access to schemas

4. Recall in reverse order: when events are recalled in forward order - witness reconstructs based on their schemas, but in reverse order - schemas cannot be assessed, so more accurate