4.1.2 Eye Witness Testimony - misleading information

Question 1

Research on leading questions - experimenter

Answer 1

Crime incident
LOFTUS AND PALMER
1974

Question 2

Research on leading questions - procedure

Answer 2

LOFTUS AND PALMER
45 student participants watched clips of 7 different car accidents and then were asked leading questions about them.
In the critical question (leading question or misleading information) the participants were asked to describe how fast the cars were going.
There were 5 different groups of participants and 5 different verbs were used to describe speed varying in severity (contacted, hit, bumped, collided + smashed)

Question 3

Research on leading questions - results

Answer 3

LOFTUS AND PALMER
As the verb ‘smashed’ has connotations with increased speed, this group estimated the speed as higher than the other groups. This shows that misleading or suggestive information can distort Eye Witness Memory.

Question 4

Research on leading questions - findings

Answer 4

LOFTUS AND PALMER
The mean estimated speed was calculated for all 5 groups. The verb ‘contacted’ (the least severe) gave the average speed of 31.8 mph, whereas the verb ‘smashed’ (the most severe) gave an average speed of 40.5mph.
This showed that the leading question, in this case the severity of the verb used, biased the eyewitness’s recall of the event.

Question 5

How do leading questions affect EWT?

Answer 5

The ‘response-bias’ explanation suggests that the wording of the question has no real effect on the participants’ memories, but just influences how they describe the answer.

LOFTUS AND PALMER (1974) conducted a second experiment that supported the substitution explanation, which proposes that the wording of a leading question changes the participant’s memory of a film clip.

Question 6

Experiment two

Answer 6

LOFTUS AND PALMER
150 student participants were shown a short film that showed a multi-vehicle car accident and they were asked questions about it. The participants were split into 3 groups (with 50 in each group).
1st group – ‘how fast were the cars going when they hit each other?’
2nd group – ‘how fast were the cars going when they smashed into each other?’
3rd group – asked nothing about the speed
All groups returned a week later and were asked:
“Did you see any broken glass?” even though there was none in the film.

Question 7

Experiment two - results

Answer 7

Response Smashed Hit Control
Yes 16 7 6
No 34 43 44

Question 8

Research on leading questions - result

Answer 8

LOFTUS AND PALMER
Contacted - 31.8 mph
Hit - 34.0 mph
Bumped - 38.1 mph
Collided - 39.3 mph
Smashed - 40.8 mph

Question 9

Research on post-event discussion - experimenter

Answer 9

Eyewitnesses to a crime may sometimes discuss their experience and memories with each other.

Fiona Gabbert et. Al (2003) looked at post-event discussion (PED)

Question 10

Research on post-event discussion - procedure

Answer 10

Fiona Gabbert et. al (20003)

Studied participants in pairs

Each participant watched a video of the same crime but filmed from different points of view

Each participant could see something the other could not

Both participants then discussed what they had seen before individually completing a test of recall

Question 11

Research on post-event discussion - findings

Answer 11

Fiona Gabbert et. al (2003)

71% of participants mistakenly recalled aspects of the event that they did not see in the video but had picked up in the discussion

They also completed this study with a control group where NO discussion occurred. In this experiment there was 0%

This was evidence of memory conformity

Question 12

Why does post-event discussion affect EWT? - explanation one

Answer 12

Memory contamination

When co-witnesses to a crime discuss it with others, their testimonies become altered or distorted

This is because they combine (mis)information from other witnesses with their own memories

Question 13

Why does post-event discussion affect EWT? - explanation two

Answer 13

Memory conformity

Gabbert et al. concluded that witnesses often go along with each other, either to win social approval or because they believe the other witnesses are right and they are wrong. Unlike with memory contamination, the actual memory is unchanged

Question 14

Research on post-event discussion evaluation - real world applications

Answer 14

Important practical uses in the criminal justice system – the consequence of inaccurate EWT can be very serious

Loftus (1975) believes that leading questions can have such a distorting effect on memory that police officers need to be extremely careful about how they phrase their questions when interviewing eyewitnesses

Psychologists are sometimes asked to act as expert witnesses in court trials and explain the limits on EWT to the juries

Question 15

Research on post-event discussion evaluation - real world application counterpoint

Answer 15

The practical applications of EWT may be affected by issues with research

Loftus and Palmer’s research was carried out in a lab – the participants watched the crashes on a screen

This is a very different experience to real life and a lot less stressful

Rachel Foster et. Al (1994) stated that what an eyewitness remembers in real-life can have important consequences. However, responses given in a lab situation are less important so participants may be less motivated to be accurate

This suggests that the research by Loftus and Palmer is too pessimistic about the effects of misleading information – EWT may be more trustworthy and reliable that many studies suggest

Question 16

Research on post-event discussion evaluation - evidence against substitution

Answer 16

• One limitation of the substitution explanation is that EWT is more accurate for some aspects of an event than for others
• Rachel Sunderland and Harlene Hayne (2001) showed participants a video clip
• When participants were later asked misleading questions – recall was more accurate for central details rather than the peripheral ones
• The participants attention was focussed on the central focus and these memories were relatively resistant to misleading information
• This suggests that the original memories for central details survived and were not distorted, an outcome that is not predicted by the substitution explanation

Question 17

Research on post-event discussion evaluation - evidence challenging memory conformity

Answer 17

Evidence challenging memory conformity:
* Another limitation of the memory conformity explanation – evidence that post-event discussions actually alters EWT
* Elin Skagerberg and Daniel Wright (2008) showed their participants film clips. There were two different versions e.g. 1st clip the mugger had dark brown hair and the 2nd clip the mugger had light brown hair
* Participants discussed the clips in pairs – each having seen the two versions
* They did not report what they had seen or what they had discussed between themselves but instead a ‘blend’ between the two
* This suggests that the memory itself is distorted through contamination by misleading post-event discussion

Question 18

Research on post-event discussion evaluation - demand characteristics

Answer 18

Demand characteristics:
* Lab studies have identified misleading information as a cause of inaccurate EWT
* Maria Zaragoza and Michael McCloskey (1989) argued that many answers given by participants in lab studies are due to demand characteristics
* Participants want to be helpful and not let the researcher down so they guess when they are asked a question that they don’t know the answer to

Question 19

Anxiety - weapon focus

Answer 19

Anxiety has a negative effect in recall (weapon focus):
* Psychological arousal in the body prevents us from paying attention to important cues – recall is worse.
* Looking at the effect of anxiety and EWT when a weapon is present.
* The weapon creates anxiety which reduces the witness’s recall of the event.

Question 20

Anxiety weapon focus study - procedure

Answer 20

Craig Johnson and William Scott (1976)
Procedure: The participants believed they were taking part in a lab experiment and were seated in the waiting room.
There were two different groups:
* High anxiety condition – overheard a heated argument, smashed glass and then a man walking out of the room with a knife covered in blood
* Low anxiety condition – overhead a casual conversation and then a man walking out of the room carrying a pen with grease on his hands

Question 21

Anxiety weapon focus study - findings and conclusion

Answer 21

Craig Johnson and William Scott (1976)
Findings and conclusions: The participants were then shown 50 photos and they had to correctly pick out the man they had seen
49% who had seen the man carrying a pen were able to identify him
33% were able to identify the man with the knife/blood
The tunnel theory of memory argues that people have enhanced memory for central events – weapon focus as a result of anxiety can have this effect

Question 22

Weapon focus evaluation

Answer 22

• Unusualness NOT anxiety
• One limitation of Johnson and Scott’s study (knife/pen) is that it may NOT have test anxiety
• Focussing on the object being carried may have been surprised rather than being scared

Question 23

Weapon focus evaluation - study

Answer 23

Kerry Pickel (1998)
conducted an experiment in a hairdressers using the following four items – a handgun, a wallet, scissors and raw chicken.
High anxiety, low unusualness = scissors
High unusualness = chicken/handgun
Eyewitness accuracy was significantly poorer in the high unusualness conditions – chicken and handgun
This suggests that the weapon focus effect is due to unusualness rather than anxiety

Question 24

Weapon focus evaluation - support for negative effects

Answer 24

• Tim Valentine and Jan Mesout (2009) supports the research on weapon focus – negative effects on recall
• They used an objective measure (heart rate) to divide participants into high and low anxiety level groups
• In the study, anxiety disrupted the participants’ ability to recall details about the actor in the London Dungeon
• Therefore, high levels of anxiety do have a negative effect on the immediate eyewitness recall of a stressful event

Question 25

Anxiety has a positive effect on recall

Answer 25

• Witnessing a stressful event creates anxiety through psychological arousal within the body
• Fight or flight is triggered – this may improve memory as we become aware of cues in the situation

Question 26

Anxiety has a positive effect on recall

Answer 26

John Yuille and Judith Cutshall (1986)
Procedure:
* Study of an actual shooting in a gun shop in Vancouver, Canada.
* The shop owner shot the thief dead.
* 21 witnesses – 13 took part in the study
* They were interviewed 4/5 months after the event and these interviews were compared to the original police interviews
* Accuracy measured – number of details reported in each account
* Had to rate how stressful the incident was (7 point scale) and whether they had emotional problems (sleeplessness)
Findings and conclusions:
* Witnesses were very accurate and very little changed in recall – some details were less accurate (colours, age, height, weight)
* Those who reported the highest levels of stress were most accurate.
* This suggested that anxiety does not have a detrimental effect on the accuracy of eyewitness memory and may even enhance it

Question 27

Support for positive effects

Answer 27

• Sven-Ake Christianson and Birgitta Hubinette (1993)
• Interviewed 58 witnesses to actual bank robberies in Sweden
• Some witnesses were directly involved (e.g. bank worker) and others were indirectly involved (e.g. bystander)
• The researchers assumed (hypothesised) that those directly involved would experience the most anxiety
• It was found that recall was more than 75% accurate across all witnesses
• The direct victims (experiencing higher anxiety) were even more accurate
• These findings from actual crimes show that anxiety does not reduce the accuracy of recall and may even enhance it

Question 28

Positive effects counterpoint

Answer 28

• Christianson and Hubinette interviewed their participants several months after the event had taken place – between 4-15 months
• The researchers had no control over the participants in this time – post-event discussion/news reports
• Therefore, the effects of anxiety may have been overwhelmed by other factors and impossible to accurately assess
• Therefore, it is possible that a lack of control over confounding variables may be responsible for the findings, invalidating the research

Question 29

Explaining the contradictory findings

Answer 29

Yerkes and Dobson – inverted u theory of arousal

Yerkes and Dobson (1908) looked at the relationship between emotional arousal and performance
Deffenbacher (1983) reviewed 21 studies of EWT and notified contradictory findings of the effects of anxiety
He used Yerkes and Dobson’s law to explain this
When you witness a crime/accident you become emotionally and physically aroused
Lower levels of arousal/anxiety produce lower levels of recall accuracy
Memory becomes more accurate as the level of arousal/anxiety increases
There is an optimum level of arousal/anxiety where there is maximum accuracy – over this level, recall suffers drastically