Eye Witness Testimony Flashcards
Loftus 1975- misleading information/question.
Misleading questions
Presented a film leading up to a car accident
Split into TWO groups
Control and experimental
Control was asked the correct question
‘How fast the white sports car going when it passed the barn while travelling along country road?’
Experimental group was asked
How fast was the white sports care going when it passed the barn
What is EWT?
Eye witness testimony is a statement about what has been seen.
How many said yes to seeing a barn from the experimental group in Loftus’ 1975 study?
17%
Why did the control group from Loftus 1975 say there was a barn though it wasn’t mentioned to them?
Post event info interfered with their testimony.
Loftus 1980-
Testing demand characteristics.
Loftus 1975
Misleading info & question.
Loftus 1980- demand characteristics.
Included a incentive.
Reward for correct answers.
Group1- film involving a pedestrian being knocked over after a car had stopped at a stop sign.
2- same sign but stopped at a yield sign.
When questioned some were misleading.
People who saw the stop sign we’re mislead by a yield sign ( in the question)
Then told Ppts to look to slides and say which ones were included in the clip.
Four groups.
1- no reward
2- $1 dollar for each correct answer.
3 - $5 dollar for each answer.
4- $25 offered to the person in the group who scored most.
70% got answer wrong when misleading question was presented.
Original memory placed with misleading post event info when presented with incentive.
Incentive didn’t positively affect testimony.
Name the 4 factors that effect eye witness testimony
misleading questions
anxiety
age
stereotypes
Schooler et al 1986
Those who weren’t mislead and saw a stop sign did give richer detail.
Loftus and zanni - 1975 vocabulary of question.
Film of car accident. Questions. 'A' broken headlight>>> 7% reported seeing one 'the' broken headlight.>>> 17% saw one. NO BROKEN HEADLIGHT.
Loftus and Palmer 1974 verb change.
‘How fast were the cars going when they hit each other?’
HIT changed to smashed,bumped,collided
Smashed = highest estimate
Contacted = lowest estimate
How many Ppts said yes to ‘a’ broken headlight in Loftus and zanni study?
7%
Loftus and Zanni- how many said yes to ‘the’ broken headlight?
17%
List 1986
Said that Ppts reported high probability events then low ones.
Foster 1994
Anxiety on EWT,
2 groups. One thought it would have an effect on trial and second though film was a simulation.
Ppts accurate if they thought evidence would result in real conviction?
Video of bank robbery.
Had to pick out bank robber from identity parade.
People who thought it was real were more accurate.
Loftus 1979 - individual differences and EWT.
Red purse theft
Mislead that it was in fact BROWN.
2 Ppts resisted central detail of theft. Colour of purse.
Others gave minor details of theft…..
Some may be uncertain on details that are small.
If striking and obvious more accurate.
Deffenbacher 2004
2 Meta analysis.
Stress and EWT.
1st meta analysis- 27 studies & 1727 Ppts «_space;eyewitnesses who had higher levels of stress identified few correct faces of perpetrator….. 42%
Low stress= 54%
2nd meta analysis- crime scene detail. Accurate recall 64% low stress 52%. High stress So high stress is ineffective for accurate recall
Johnson and Scott
1976
Johnson and Scott 1976
Weapon recall
No weapon condition- overheard conversation in room then man appeared with a pen covered with grease.
Weapon condition- overheard a heated convo then saw a guy holding a paper knife covered in blood.
Fifty photos shown-
49% no weapon were accurate.
33% in weapon condition.
Anxiety distracts witness from other detail.
Reduces accuracy of witness recall.
How many Ppts were accurate in the no weapon condition? ( Johnson & Scott study)
49% were accurate.
How many were accurate in weapon condition in Johnson and Scott study?
33%
What did the Johnson and Scott study conclude?
Anxiety (from seeing the weapon)distracts witness from other significant details.
Yulie and Cutshall
- pro stress and EWT.
Yulie and Cutshall (1998)
13 witnessed stressful event of armed thief at gun shop.
High levels of stress had 88% accuracy of recalling events.
Valentine
2003 stress and accuracy of EWT
Valentine 2003
Analysed questionnaire
640 eye witnesses.
Presence of weapon no affect on accuracy of identifying the suspect.
Ceci and bruck (1999)
Factors that influence EWT Misleading questions Close ended questions Repetitive questioning Adult influences. Mainly for children.
Sam stone study - Leichtman and Ceci (1995)
2 min visit in classroom by Man Sam stone
Pre school children 3-4yrs
10 weeks children were interviewed using misleading questions
Dirtied the teddy bear or ripped the book?
‘Did you see Sam stone rip up book?’
72% = remembered. 44%=seen
20% had maintained with seen.
Sam stone study by Leichtman and Ceci ….. What year?
(1995)
Cohen and Faulkner
1989- age and EWT.
Cohen and Faulkner 1989
Silent video clip to middle aged Ppts and elderly.
10mins later they read a misleading written account.
After a further 10mins a questionnaire was given to them
Elderly group more likely to claim info had been originally witnessed in film rather then it being false.
Findings - elderly less likely than younger adults to give an accurate recall of events because of post event info.
Findings of Cohen and Faulkner (1989)
Found out that elderly were to give less accurate info than young adults because of post event info.
Yarmey et al
1984 memory recall
Yarmey et al 1984
Saw slides of staged sexual assault
Had to answer a questionnaire on what they had seen
80% elderly failed to mention crucial items KNIFE
20% of younger failed to mention this KNIFE
Coxon and valentine
1997 age and misleading info
Coxon and valentine 1997
Goes against Yarmey and Cohen and Faulkner.
Tested EWT on young children,young adults and elderly.
Short video of baby abduction by a posed nurse.
Misleading questions asked and answered.
Elderly less likely to recall misleading info so accuracy was high. 37% misled.
Adults - 39% and children 60% misled.
