M- Eyewitness Testimony

Question 1

What is eyewitness testimony?

Answer 1

• Eyewitness testimony (EWT) is the evidence supplied to a court by people who have seen a crime, based on their memory of the incident.
• This evidence can include an identification of the perpetrator or details of the crime (sequence of events, the time of day etc.).

Question 2

What are leading questions?

Answer 2

Leading questions are questions that are phrased in such a way as to encourage
a witness to give a certain answer.

Question 3

What does the response-bias explanation argue?

Answer 3

The response-bias explanation argues that

leading questions do not affect memory, merely the answer a person chooses to give.

Question 4

What does the substitution-bias explanation argue?

Answer 4

The substitution-bias explanation proposes that leading

questions distort memories because they contain misleading information.

Question 5

Describe the procedure of Loftus and Palmer’s investigation.

Answer 5

• Loftus and Palmer (1974) showed 45 American students a film of a car crash and then asked them to estimate the speed that the cars were
  travelling when they crashed.
• However different verbs were used in the
  question depending on the condition.
• The verbs were contacted, hit, bumped,
  collided, or smashed.

Question 6

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

Answer 6

• Participants in the ‘contacted’ condition estimated the speed as
  31mph but in the ‘smashed’ condition participants estimated the speed as 41mph.
• A week later participants were asked if they saw any broken glass, even though
  there was no broken glass shown in the film. 32% of the participants in the
  ‘smashed’ condition reported seeing broken glass compared to only 12% in the
  control condition. - This shows that leading questions have a significant impact on
  what people recall and can change a person’s entire memory of an event.

Question 7

Evaluate leading questions.

Answer 7

(+) Loftus and Palmer’s study was a laboratory experiment and was therefore highly controlled.
- This reduces the chance of extraneous variables, increasing the validity of the
results.
- Furthermore, it is easy for psychologists to replicate their research
study to see if the same results are found, meaning the study is reliable.

(-) Contradictory real life research

• Yuille & Cutshall studied a real-life situation of a shooting outside a gun shop in Canada.
• They examined witnesses’ recall of a real-life crime five months after the incident and asked them two misleading questions.
• They found the misleading questions did not alter accuracy of recall from their original statements.
• This is a problem as in Loftus’ research the important information (the speed of the car) was distorted simply by the verb used.
• However, EWT studied in real life situations has contradictory results, where misleading information did not distort accuracy of recall
• Therefore the validity of Loftus’ methodology and findings are reduced

Question 8

What is post-event discussion?

Answer 8

When witnesses to an event discuss what they have experienced after the event

Question 9

Why is post-event discussion argued to affect accuracy of EWT?

Answer 9

1) Memory contamination: Witnesses mix info from other witnesses into their own memories.
2) Memory conformity: Witnesses pick up details from the eye witness testimony of other witnesses because they want social approval or because they believe other witnesses are right, and they are wrong.

Question 10

Describe Gabbert et al’s study.

Answer 10

• Pps were put in pairs and watched video of a crime but filmed from different views- so they saw slightly different elements.
• Before they were asked about the content of the video, the pps were allowed to discuss what they had seen.
• 71% of pps mentioned aspects of the video they had not seen, but their partner had.
• Therefore, we can conclude the witnesses will absorb information from other witnesses, either because of memory contamination or memory conformity.

Question 11

Evaluate post-event discussion.

Answer 11

(+) Gabbert et al’s study has population validity.
- Two different populations, students and older adults, were compared and there were no significant differences between these two groups.
- This allows us to conclude that post-event discussion affects
younger and older adults in a similar way.

(-) This study lacks ecological validity.

• The participants knew they were taking part in an experiment and they therefore are more likely to have paid close attention to the details of the video clip.
• The results do not reflect real life where witnesses may be exposed to less information.