EWT

Question 1

What is an EWT?

Answer 1

The ability of people to remember the details of events, such as accidents and crimes, which they themselves have observed.

Question 2

What factors can affect an EWT?

Answer 2

Factors such as misleading information, leading questions and anxiety.

Question 3

What is EWT used for?

Answer 3

• Recorded in a police statement
• Verbal testimony to be used as evidence in a court of law

Question 4

What is misleading information?

Answer 4

Incorrect information given to the eyewitness usually after the event.

Question 5

What forms can misleading information take?

Answer 5

Leading questions and post-event discussion between co-witnesses and/or other people.

Question 6

What is a leading question? What is an example?

Answer 6

A question which, because of the way it is phrased, suggests a certain answer. E.g. “Was the knife in the accused’s left hand?”. This suggests the answer is ‘left hand’.

Question 7

Who investigated the effect of leading questions on eyewitness testimony?

Answer 7

Loftus and Palmer

Question 8

What was Loftus and Palmer’s procedure?

Answer 8

A laboratory experiment. Three groups of students, after watching a film of a car crash were asked questions (an independent measures design): -
The first group were asked – “How fast were the cars going when they hit each other?”
For the other group the words: - smashed into each other were substituted.
A control group were not asked about speed.
A week later they were re-interviewed and asked: - “Did you see any broken glass?”

Question 9

What were the results of Loftus and Palmer’s study?

Answer 9

The smashed group’s average estimated speed was 41mph
The hit group’s average estimated speed was 38mph
Although there was no broken glass at the scene 32% of the participants who heard the word smashed said there was, compared to only 14% of the hit group and only 12% of the control group.

Question 10

What was there conclusion?

Answer 10

The participants had unconsciously incorporated connotations (of speed and force) into their memory of the event and it had affected their judgement of speed and memory of the scene.

Question 11

What are the two explanations for why leading questions affect EWT?

Answer 11

Response bias and Substitution

Question 12

What is the response bias explanation? E.g

Answer 12

The wording of the question doesn’t affect participants’ memories, it just influences how they decide to answer.
E.g. When a participant is asked a leading question using the word smashed – this encourages them to estimate a higher speed

Question 13

What is the substitution explanation? E.g

Answer 13

The wording of the question actually changes the memory of the film clip
E.g. Participants who originally heard ‘smashed’, were more likely to report broken glass when asked later

Question 14

What is post-event discussion?

Answer 14

Occurs when there is more than one witness to an event. Witnesses may discuss what they have seen with their co-witnesses or with other people. This may influence the accuracy of each witness’s recall of the event.

Question 15

What can happen when co-witnesses discuss?

Answer 15

When co-witnesses discuss the observed crime with each other, their EWT may become contaminated. This is because they combine (mis)information from other witnesses with their own memories

Question 16

Who investigated the effects of post-event discussion on the accuracy of EWT?

Answer 16

Gabbert

Question 17

What was Gabbert’s procedure?

Answer 17

Participants were studied in pairs
Each participant watched a video of the same crime, but filmed from different points of view (positions)
Each participant could see elements of the events that the other could not (e.g. only one of the participants could see the title of the book carried by a young woman)
Both participants then discussed what they’d seen before taking a recall test on their own

Question 18

What were the results of Gabbert’s study?

Answer 18

71% of the participants mistakenly recalled aspects of the event they did not see but had picked up from discussion with their partner
In the control group, where there was no discussion, there was no information incorrectly recalled (0%)

Question 19

What was the conclusion of Gabbert’s study?

Answer 19

Witnesses often go along with each other
To gain social approval or because they believe the other witnesses are right and they are wrong
Gabbert (2003) called this memory conformity

Question 20

What is anxiety? What does it include?

Answer 20

A state of emotional and physical arousal. The emotions include having worried thoughts and feelings of tension. Physical changes include an increased heart rate and sweatiness. Anxiety is a normal reaction to stressful situations, but can affect the accuracy and detail of eyewitness testimony.

Question 21

What is the negative effect of anxiety on EWT?

Answer 21

Anxiety causes physical arousal in the body which prevents us from paying attention to vital cues – recall is worse.

Question 22

What is weapon focus effect?

Answer 22

The effect of weapons (which cause anxiety) on the accuracy of witness recall

Question 23

Who investigated the effect of weapons on the accuracy of EWT?

Answer 23

Johnson and Scott

Question 24

What was Johnson and Scott’s procedure?

Answer 24

Participants were told they would be taking part in a lab study
Whilst sitting in a waiting room participants heard an argument in the room next door
Low anxiety condition – a man walked through the waiting room carrying a pen with grease on his hands
High anxiety condition – a man walked through the waiting room carrying a paper knife that was covered in blood

Question 25

What was the result of Johnson and Scott’s study?

Answer 25

Participants then had to identify the man they saw from 50 photos
Those who saw the man with the pen (low anxiety) – 49% could correctly identify him
Those who saw the man with the knife (high anxiety) – 33% could accurately identify him

Question 26

What was the tunnel theory of memory?

Answer 26

A witnesses attention narrows to focus on a weapon, because it is a source of anxiety

Question 27

What is the positive effect of EWT?

Answer 27

The stress of witnessing a crime creates anxiety through physiological arousal within the body.

The fight-or-flight response is triggered which increases alertness and improves our memory for the crime as we become more alert of cues in the situation.

Question 28

Who investigated the effects of anxiety on EWT?

Answer 28

Yuille and Cutshall

Question 29

What was the procedure of Yuille and Cutshall’s study?

Answer 29

Yuille & Cutshall interviewed eyewitnesses of a real life shooting in a gun shop in Vancouver, Canada
Out of the 21 witnesses, 13 agreed to take part in the study
The interviews took place 4-5 months after the incident and these were compared with the original police interviews on the day of the shooting
The more details recalled, the better the accuracy
Witnesses also rated their stress levels at the time of the incident on a 7-point scale
They were asked if they had any emotional problems since the incident (e.g. sleeplessness)

Question 30

What were the findings of Yuille and Cutshall’s study?

Answer 30

Witnesses were very accurate in their accounts
There was little change in their accuracy after 5 months
Some details were less accurate (e.g. colours of items and age/height/weight estimates)
Participants who reported the highest levels of stress were most accurate (88%) compared to the less-stressed group (75%)