LOFTUS AND PALMER (1974)
AIMS:
● To investigate how leading questions affect eyewitness testimony
PROCEDURE:
● Lab Study
● Sample of 45 participants
● Split into 5 conditions
● Watched a video and asked “how fast were the cars going when they hit each other?”
● Only thing that changed was the verb
● Split into smashed, hit, collided, contacted and bumped
FINDINGS:
● The harsher the verb, the faster participants perceived the car to go
● Contacted mean= 31.8mph
● Smashed mean= 40.5mph
CONCLUSIONS:
● The leading question affected eye-witness testimony
● Leading questions bias memory recall
POSITIVE EVALUATIONS:
● Real-world applications- important in the criminal justice system
NEGATIVE EVALUATIONS:
● Lab study- lack of ecological validity
● Responses in lab studies are less likely to be accurate as the answers don’t matter,
unlike in the criminal justice system
, POST EVENT DISCUSSION IN EYE WITNESS TESTIMONIES
GABBERT ET AL (2003)
AIMS:
● Investigating the effect of post-event discussion on eyewitness testimony
PROCEDURE:
● Lab study
● Participants in pairs watched a video of a crime but from different perspectives
● After the video participants discussed what they saw with their partner
● Each given an individual test after the discussion to see what they could remember
● 2 conditions- post event discussion and no post event discussion
FINDINGS;
● 71% of participants mistakenly recalled aspects of the event they could not see
● In the control group 0% of participants said things they couldn’t have seen
● Evidence of memory conformity and memory contamination
CONCLUSIONS:
● Post-event discussion reduces the accuracy of eyewitness testimony
● Witnesses often go along with each other to either win social approval or because
they believe the other witnesses are right and they are wrong
POSITIVE EVALUATIONS:
● Real-world applications
NEGATIVE EVALUATIONS:
● Lab study- lack of ecological validity
● Demand characteristics- participants are in an artificial environment
● Evidence challenging memory conformity- Elin Skagerberg and Daniel Wright (2008)
- participants came to the conclusion that a woman had “medium brown” hair rather
than dark or light brown- suggests that memory is distorted through contamination by
misleading post event discussion rather than the result of memory conformity
● Eyewitness testimony is more accurate for some aspects of an event than for others