Factors affecting accuracy of eyewitness testimonies

Question 1

What are the two types of misleading information as a factor of affecting the accuracy of EWT

Answer 1

• Leading questions
• Post-event discussion

Question 2

Outline one research into leading questions

Answer 2

• 45 participants shown short video clips of cars colliding
• Split into 5 groups
• All asked About how fast were the cars going when they —— each other
• Each group given different verb to fill in blank (smashed, collided, bumped hit, contacted)
• Found when smashed was used, participants estimated cars travelled much faster (on average 40.8mph)
• When contacted was used, estimates were much slower (on average 31.8 mph)
• Verb influence participants estimates for speed, shows effect of leading questions on accuracy of EWT

Question 3

Outline final research into leading questions

Answer 3

• 150 participants viewed car crash before being asked how fast were cars going when they —-
• 50 asked with verb smashed
• 50 with verb hit
• 50 as a control group with no question
• One week later questioned on memory of event
• Asked did you see any broken glass (there wasn’t any)
• Participants who heard smashed were more likely to say yes than those who heard hit and those in control group
• Verb smashed indicated cars traveling at higher speed so more likely to result in broken glass

Question 4

Why might post-event discussion lead to inaccurate EWT?

Answer 4

• Memory contamination (recall of events influenced by our own schemas and cognitive biases, other peoples memory of events may have been combined with their own so becomes contaminated)
• Memory conformity (Witness may go along with others, even if others are wrong, wants social approval)

Question 5

Outline research into post-event discussion

Answer 5

• Participants watched video of girl stealing money from wallet
• Either tested individually (control group) or in pairs (co-witness group)
• Participants in co-witness group told that they had watched same video however they saw different perspectives of same crime and only one person actually saw girl steal
• Then they discussed crime after together
• Completed questionnaire testing memory of event
• 71% of witnesses in co-witness group recalled information they had actually not seen
• 60% said girl was guilty, despite may not have seeing her commit crime
• Post-event discussion can impact accuracy of EWT