Identify at least two factors that may affect the reliability of eye witness testimony. For each factor, explain why it affects the reliability. (12 marks)
The reliability of eye witness testimonies (EWT) has been under a lot of scrutiny recently due to the conviction of innocent people in court which has been based entirely on these accounts. One factor which has been found to affect the reliability of EWT is post-contamination and misleading questions. This suggests that memory can be distorted by the way questions are asked after the event, which causes witnesses to doubt their own memories (which could be argued is due to informational conformity- the belief that the person asking the questions knows something you don’t).
Loftus et Palmer showed videos of a car collision to participants and then asked “how fast was the car moving when it ___ into the other car?” The verb ranged from ‘collided’ to ‘smashed’. Participants who were asked the question with the verb ‘smashed’ estimated the car was moving 10mph faster than those who were asked with ‘collided’. On week later, participants were then asked to note whether they saw any broken glass at the scene (of which there was none). Participants who were asked with ‘smashed’ seemed to recall seeing broken glass more often than those who were asked with ‘collided’. This experiment provides evidence that misleading questions can contaminate and affect a persons recall as the experimenter was asking very closed and directed questions.
However, this experiment was a laboratory experiment so participants had no real moral or legal obligation to get the answers right. Although, a study which looked into a real life event by Yuille and Cutshall rather undermines this theory. Witnesses to a shooting of a thief in Vancouver were asked to be interviewed by the researchers 5 months on from the event. Participants were found to recall the same information as to what had been found in the investigation. The misleading questions appeared to have no affect on the answers the participants gave. This however, may be due to the legal obligation of their original statements which lead to a conviction, rather than the questions themselves. It may also have been due to the fact that this was quite a distinct event which they may have played through in their head. This would suggest that the rehearsal of the memory (supported by the multi-store model of memory) was actually the cause of this. A major positive of this study if that because it was a real-life event, it has applications in the real world and with real life eye witness testimonies. No psychological harm was enforced by the researchers because the harm had already been done (the witnesses had also consented to the interviews).
Other factors that affect…