Factors Affecting The Accuracy Of Eyewitness Testimony

Question 1

What are the factors affecting the accuracy of eyewitness testimony

Answer 1

• Misleading Information
• Anxiety

Question 2

Misleading information

Answer 2

Incorrect information given to an eyewitness usually after the event

Question 3

Research on leading questions- Loftus and Palmer

Answer 3

• The wording of a question may lead or mislead you to give a certain answer
• Loftus and Palmer
• 45 participants watched film clips of a car accident
• Then they asked the questions about the accident- how fast were the cars going when they hit each other
• 5 groups were given different verbs (hit, contacted, bumped, collided, smashed)
• The mean estimated speed was calculated for each participant group
• Verb contacted estimated 31.8 mph
• Verb smashed estimated 40.5 mph

Question 4

Why do leading questions affect EWT- Response bias

Answer 4

• Response bias explanation suggests that the wording of the question has no real effect on the participants’ memories but just influences how they decide to answer
• Eg. ‘smashed’ leads people to estimate a higher speed

Question 5

Why do leading questions affect EWT- Wording of questions
(Loftus and Palmer)

Answer 5

Loftus and Palmer
- Wording of question can change participants memories
- Participants who heard smashed were more likely to report seeing broken glass than those who heard hit
- Verb altered their memory of the incident

Question 6

Research on post-event discussion- (Gabbert)

Answer 6

• Studied participants in pairs
• Each participant watched a video of the same crime but filmed from different points of view
• Means that each participant can see things in the video that others could not
• Then they discussed what they had seen before individually completing the task
• Found 71% of the participants mistakenly recalled aspects of the event that they did not see in the video but had picked up in the discussion
• Memory conformity

Question 7

Why does post-event discussion affect EWT- Memory contamination

Answer 7

• Memory contamination- co-witnesses to a crime discuss it with each other their EWT may become altered, this is because they combine information from other witnesses with their own memories

Question 8

Why does post-event discussion affect EWT- Memory conformity

Answer 8

• Memory conformity- 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, however the actual memory is unchanged

Question 9

Misleading information evaluation points- Real world Application

Answer 9

STRENGTH

Insights applied to police interviewing and expert witnesses

Question 10

Misleading information evaluation points- Counterpoint

Answer 10

LIMITATION

Film clips in lab are less stressful than everyday life, no consequences. EWT more reliable

Question 11

Misleading information evaluation points- Evidence against substitution

Answer 11

STRENGTH

Central details not much affected by misleading information

Question 12

Misleading information evaluation points- Evidence challenging memory conformity

Answer 12

STRENGTH

Post event information on hair colour blended, supporting contamination

Question 13

Misleading information evaluation points- Demand characteristics

Answer 13

LIMITATION

Lab environment enables control but answers in lab studies influenced by desire to be helpful

Question 14

How does anxiety have a negative effect on recall
(Johnson and Scott)

Answer 14

• Participants believed they were taking part in a lab study- seated in waiting room
• Low anxiety group- heard casual conversation then saw a man walk past them carrying a pen with grease on their hands
• High anxiety group- heard heated argument with sound of glass breaking then saw man walk out holding a blood covered knife
• Participants later picked out the man from a set of 50 photos
• 49% who had seen the man carrying the pen were able to identify him
• Participants who had seen the man holding the blood covered knife was 33%

Question 15

What is weapon focus

Answer 15

Weapon focus (focus on the weapon, reducing a witness’s recall for other details of the event)

Question 16

What is tunnel theory

Answer 16

Tunnel theory of memory argues that people have enhanced memory for central events

Question 17

why does anxiety have a negative effect

Answer 17

Anxiety creates physiological arousal in the body which prevents us paying attention to important cues, so recall is worse

Question 18

How does anxiety have a positive effect on recall
(Yuille and Cutshall)

Answer 18

Yuille and Cutshall
- Study of an actual shooting in a gun shop
21 witnesses- 13 took part in the study
- Interviewed 4-5 months after the incident and these interviews where compared with the original police interviews at the time of the shooting
- Accuracy was determined by the number of details reported in each account
- Also asked how stressed they felt at the time of the incident and whether they has any emotional problems since the event
- The witnesses were very accurate in their accounts- little change
- Some details were less accurate such as age/height estimates etc
- Participants who reported feeling high levels of stress were most accurate

Question 19

Why does anxiety have a positive effect

Answer 19

Witnessing a stressful event creates anxiety through physiological arousal within the body. The fight or flight response is triggered, increasing alertness. Therefore improving memory for the event as we become more aware of cues in the situation

Question 20

Explain the contradictory findings of anxiety effect on EWT- Yerkes and Dodson

Answer 20

• Relationship between emotional arousal and performance
• Inverted U theory

Question 21

Explain the contradictory findings of anxiety effect on EWT- Deffenbacher

Answer 21

• Reviewed 21 studies of EWT
• Used Yerkes-Dodson law to explain findings
• When we witness a crime we become emotionally and physiologically aroused
• Lower levels of anxiety produce lower levels of recall accuracy and then memory becomes more accurate as the level of anxiety increases
• Optimum level of anxiety = Maximum accuracy

Question 22

Evaluation points on the effects of anxiety on EWT- Unusualness not anxiety

Answer 22

LIMITATION
Poor recall due to unusualness (chicken and handgun), not anxiety (Pickel)

Question 23

Evaluation points on the effects of anxiety on EWT- Support for negative effects

Answer 23

STRENGTH

London Dungeon- anxiety reduced accurate recall of an individual

Question 24

Evaluation points on the effects of anxiety on EWT- Support for positive effects

Answer 24

STRENGTH

The most anxious eyewitness at bank robbery had the most accurate recall

Question 25

Evaluation points on the effects of anxiety on EWT- Problems with the inverted u theory

Answer 25

LIMITATION

Explains contradictory findings but focuses just on physical arousal, ignores cognitive aspects of anxiety