Eye Witness Testimony

Question 1

Eye Witness Testimony

Answer 1

The ability of people to remember details of events which they observed, such as crimes, accidents etc.

Question 2

Why is accuracy important for eye-witness testimony?

Answer 2

EWT is used in court trials and police interviews, so accuracy is important as it can affect the outcomes of trials, and may lead innocent people to be convicted.

Question 3

Reconstructive Memory

Answer 3

How our memories can become distorted due to factors such as misleading information.

Question 4

Misleading Information

Answer 4

In terms of EWT, this is when a witness receives incorrect information about the event.

Question 5

Schemas

Answer 5

Organised pockets of information in the mind, affected by assimilation and accomodation.

Question 6

Bartlett (1932) - Summary

Answer 6

Participants essentially played Chinese Whispers. They passed on a story to eachother and as it went on, they began to rationalise the story, removing any confusing ideas, making it shorter and more conventional. This supports reconstructive memory, as participants’ schemas containing information of the real world distorted their recall of the story.

Question 7

Bartlett (1932) - Strengths

Answer 7

• Good support for reconstructive memory.
• Results have been validated with studies such as Loftus and Palmer (1974), finding similar results.
• Used a story from a different culture to ensure no participants would be familiar with it. This could have been an extraneous variable otherwise, making the study more valid.

Question 8

Bartlett (1932) - Limitations

Answer 8

• The study is very outdated, may lack temporal validity.
• Details of the procedure are missing, meaning it would be very difficult to replicate, lowering validity.
• There is no statistical information concerning the findings of the study, making the results difficult to use.
• Lacks population validity, the sample only consisted of 20 UK students.

Question 9

Leading Questions

Answer 9

Phrasing a question in a way that suggests a certain answer.

Question 10

How could leading questions affect EWT?

Answer 10

Police may direct witnesses with their questions to receive a particular answer that will help their case.

Question 11

Loftus and Palmer Experiment One (1974) - Aim

Answer 11

To investigate how information supplied after an event (leading questions) can affect a witness’ memory.

Question 12

Loftus and Palmer Experiment One (1974) - Procedure

Answer 12

Participants watched a video of a car crash and were asked questions about it. The critical question was leading, with the verb changed for different participants. They were asked: ‘about how fast were the cars going when they ____ eachother ?’ The verb was either: hit, bumped, smashed, collided, or contacted.

Question 13

Loftus and Palmer Experiment One (1974) - Results

Answer 13

Smashed - 40.8 mph
Collided - 39.3 mph
Bumped - 38.1 mph
Hit - 34 mph
Contacted - 31.8 mph

Question 14

Loftus and Palmer Experiment One (1974) - Conclusion

Answer 14

The verb used unconsciously shifts our memory of the speed. Overall, people are not good at judging the speed of the vehicle.

Question 15

Which two explanations are there for Loftus and Palmer’s results?

Answer 15

Response-bias factors, and memory representation changes.

Question 16

Response-Bias Factors

Answer 16

Misleading information may have influenced the answer, but didn’t lead to false memory of the event. Speed estimates only occur due to the critical word.

Question 17

Memory Representation Changes

Answer 17

The critical verb changes a person’s perception of the accident - this is then stored in a person’s memory of the event.

Question 18

Loftus and Palmer Experiment Two (1974) - Aim

Answer 18

To investigate whether the change in estimates in experiment one were due to response bias or memory representation changes.

Question 19

Loftus and Palmer Experiment Two (1974) - Procedure

Answer 19

In a lab, 150 students were divided into three groups and watched a car crash video. They then described the video and answered a questionnaire with the same critical question. One week later, without watching the clip again, they were given another questionnaire, asking ‘did you see any broken glass?’ There was no broken glass in the film.

Question 20

Loftus and Palmer Experiment Two (1974) - Findings

Answer 20

Smashed - 10.46 mph, 16 saw glass, 34 didn’t.
Hit - 8 mph, 7 saw glass, 43 didn’t.
Control - 6 saw glass, 44 didn’t.

Question 21

Loftus and Palmer Experiment Two (1974) - Conclusion

Answer 21

Participants are not very good at judging speed. The smashed condition reported seeing significantly higher levels of glass than hit and control conditions, suggesting the verb used can distort the participants’ memory.

Question 22

Which explanation does Loftus and Palmer’s second experiment support?

Answer 22

This supports the memory representation changes explanation, as the memory of the clip was distorted, even causing some to see broken glass that wasn’t there.

Question 23

Loftus and Palmer (1974) - Strengths

Answer 23

• Lab experiment - good control of extraneous variables, good validity.
• Application - provides good support of reconstructive memory, which is useful in police questionning.
• The procedure would be easily replicated - good reliability.

Question 24

Loftus and Palmer (1974) - Limitations

Answer 24

• Lowered validity due to artificial environment and task. These may affect results, with demand characteristics, lack of ecological validity, and mundane realism.
• Lack of reliability - results differ in Yuille and Cutshall (1986).
• All participants were students at one university - low population validity.

Question 25

Post-Event Discussion

Answer 25

When there is more than one witness to an event, witnesses discuss what they have seen with others. This can influence the accuracy of the witnesses’ recall.

Question 26

Gabbert et al. (2003) - Aim

Answer 26

To investigate the effect of post-event discussion on the accuracy of eye witness testimony.

Question 27

Gabbert et al. (2003) - Procedure

Question 28

Gabbert et al. (2003) - Findings

Answer 28

71% of the co-witness group recalled information that they had not actually seen and 60% said that the girl was guilty, despite not even witnessing the crime. This was 0% in the control group.

Question 29

Gabbert et al. (2003) - Conclusion

Answer 29

Findings suggest that post-event discussion negatively affects the accuracy of EWT, as it can distort peoples’ memory.

Question 30

Gabbert et al. (2003) - Strengths

Answer 30

• High population validity - tested on students and older people, and both found similar results.
• Controlled lab environment, high validity.

Question 31

Gabbert et al. (2003) - Limitations

Answer 31

• Low ecological validity - artificial environment.
• Demand characteristics - may have been playing close attention as they knew they’d be questioned.
• Low internal validity - incorrect answers here may come from social conformity, or bad memory, not the discussion.

Question 32

Who’s research demonstrates that anxiety may have a positive effect on EWT accuracy?

Answer 32

Yuille and Cutshall (1986).

Question 33

Yuille and Cutshall (1986) - Aim

Answer 33

To investigate if anxiety could positively affect recall of a stressful event.

Question 34

Yuille and Cutshall (1986) - Procedure

Answer 34

13 witnesses of an armed robbery were interviewed 4-5 months after the incident. They were asked to rate their stress level on a 7-point scale. These interviews were then compared to police interviews.

Question 35

Yuille and Cutshall (1986) - Findings

Answer 35

Those who reported lower levels of anxiety had 75% accurate recall, while those with higher anxiety were 88% accurate.

Question 36

Yuille and Cutshall (1986) - Conclusion

Answer 36

Anxiety can positively affect recall, meaning it can be useful in EWT.

Question 37

Yuille and Cutshall (1986) - Strengths

Answer 37

• Interviews had a controlled lab setting, good reliability.
• Good application, helping to establish the reliability of EWT.
• The event that they recalled had high ecological validity - they were actually present at a crime, not just watching a video.
• Consent was received from the participants, eight witnesses decided not to take part.

Question 38

Yuille and Cutshall (1986) - Limitations

Answer 38

• The use of a case study makes the findings ungeneralisable. The specificity of the situation they were in cannot be generalised to others.
• Only 13 participants used, low population validity.
• Qualitative data was changed to quantative, lowering validity.
• Harm to participants may have been caused. The event was traumatic and to be reminded of it, without full briefing, may have caused harm.

Question 39

Who’s research demonstrates that anxiety can have a negative affect on EWT accuracy?

Answer 39

Peters (1988).

Question 40

Peters (1988) - Aim

Answer 40

To investigate whether anxiety levels can affect the accuracy of recall.

Question 41

Peters (1988) - Procedure

Answer 41

The sample consisted of a group of patients at a health centre, needing injections. A nurse then gave them injections and they went home. One week later, they were asked to select a photo of the researcher, and the nurse from a set of photos.

Question 42

Peters (1988) - Findings

Answer 42

Recall was better when selecting the photo of the researcher, than the photo of the nurse, possibly due to the nurse being more anxiety inducing.

Question 43

Peters (1988) - Conclusion

Answer 43

Higher levels of anxiety can negatively impact recall, making EWT of stressful events possibly less accurate.

Question 44

Peters (1988) - Strengths

Answer 44

• Good ecological validity, the participants were already there to get injections, and the setting was accurate to the task.
• Participants were recruited, and had the choice whether to take part or not.
• Good control of extraneous variables by bringing patients back to the health centre, location may effect recall (context-dependent forgetting).

Question 45

Peters (1988) - Limitations

Answer 45

• The use of a field experiment makes control of extraneous variables difficult, lowering validity.
• It is likely that participants spent more time with the researcher than the nurse.
• Mental harm may be caused to participants, they may have fears of needles.