Eyewitness Testimony Flashcards
What is eyewitness testimony (EWT)
- influential evidence supplied to a court by people who have seen a crime, based on their memory of the incident
Often includes: - sequence of events
- time of day
-perpetrator identification etc
What are leading questions
Q’s that are phrased in a way to encourage a certain answer
Response bias argues that
Leading questions don’t affect memory, only the answer someone chooses to give
Substitution bias argues that
Leading Q’s distort memories as they contain misleading info
What was Loftus & Palmer’s (1974) procedure
They 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
-> different verbs were used in the questions (contacted, hit, bumped, collided, smashed)
Loftus & Palmer (1974) Findings
Participants in the ‘contacted’ condition = 31mph estimated speed
‘Smashed’ condition = 41mph
-> a week later, participants asked if they saw any broken glass (even tho there was none)
-> 32% (‘smashed’) said yes, 12% (control) = yes
What did Loftus & Palmer show us?
That leading questions have a significant impact on what people recall & can change a persons entire memory of an event
Leading Questions AO3 - P1 lab experiment (+)
As it’s a lab experiment, it’s
- highly controlled
-> this reduces the chance of extraneous variables
-> increasing the validity of the results, and making it easy to replicate research studies, so the study is reliable (if same results are found)
AO3 - P2 ecological validity leading Q’s
The study has questionable ecological validity
-> as pps watched a video, rather than witnessing a real accident (which would give them a stronger emotional connect to the event, so less likely to be susceptible to leading Q’s)
AO3 : P3 - lacking population validity (Leading Q’s)
-> study consisted of 45 American students
- students = less experienced drivers & therefore may be less competent at estimating speeds
-> we can’t generalise the results to other populations, as more experienced drivers may be more accurate in their judgement of speeds & so less susceptible to leading Q’s
What is post-event discussion
When discussing events with others leads to misinfo (memory contamination).
-> a desire for social approval can also lead to memory conformity (when co-witnesses reach a consensus view of what happened)
What was Gabbert et al (2003) - procedure [pairs watching different videos]
- pps put in pairs and each watch a different video of the same event so that they each got unique details.
-> one condition the pairs were encouraged to discuss the event with one another before individually recalling the event.
-> other condition they did not discuss what they had seen with one another
Gabbert et al (2003) findings
71% of witnesses who had discussed the event went on to mistakenly recall details that they could not have seen themselves, but that they had learned of during the discussion with their partner
Gabbert et al 2003 AO3 - P1 population validity (+)
Two different populations (students and older adults) compared + 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.
-> there is population validity
Gabbert et Al (2003) post event discussion AO3 P2 - ecological validity
-> lacks ecological validity.
- pp’s 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.
+ results do not reflect real life where witnesses may be exposed to less information.
