Eye Witness Testimony Flashcards
What is Eye Witness Testimony?
EWT is the evidence provided in court by a person who has witnessed a crime / incident with a view to identifying the perpetrator of the crime
The accuracy of EWT can be affected by leading questions and misleading information
Outline leading questions briefly
A leading question is one that by its form or content, suggests to the witness what answer is desired or leads them to a desired answer
Eg what was the person wearing is an open question
What colour was the man’s hat was a leading question
Outline leading question using Loftus and Palmers study
Aim was to investigate the effect of leading questions in distorting the accuracy of EWT
Procedure: lab experiment w independent groups design
45 American students shown 7 films of car diff accidents
After each film asked questions including 1 critical question
About how fast were the cars going when they ———— each other?
Ppts split in 5 groups and each group asked question w different verb (hit, smashed, collided, bumped, contacted)
IV = wording of Q and DV = speed reported by ppt in mph
Findings: estimated speed was affected by verb used, group given word ‘smashed’ estimated highest speed (40.8mph) and the group given word ‘contacted’ estimated lowest speed (31.8mph)
What was concluded from Loftus and Palmers study into leading questions?
Language can have a distorting effect on EWT. This can lead to inaccurate accounts of witnessed events
Original memory could have been reconstructed, replaced or experienced interference
Has important implications for the questions used in police interviews for eyewitnesses
Outline post event discussion
PED is any info discussed after event which could influence persons memory of event (includes discussion w other witnesses, news reports, chat w friends and family etc)
Results in EWT becoming contaminated because they combine mis(information) from other witnesses w their own memories
Memory conformity is when witnesses go along with each others accounts for social approval or because they believe they are right
Source monitoring can occur, where alternative accounts are heard by individuals causing confusion and distortion in memory
Outline PED using Gabbert et als research (2003)
Aim was to investigate effects of PED on distorting the accuracy of EWT
Procedure: lab experiment
Experimental group
Paired ppts watched video same simulated robbery from diff angles, both ppts discussed what saw (PED) and then completed recall test individually
Control group watched same video but didn’t take part in PED
Findings:
71% ppts in experimental group mistakenly recalled aspects of event which didn’t see in video but picked up during PED
60% said girl was guilty (not seen her commit crime from that angle)
0% control group made errors
What did Gabbert et al conclude from his research into post event discussion?
Concluded witnesses go along w each other, for social approval or actually believe they are right
These findings have implications for forensic psychology eg ensuring police gather info from witnesses immediately after crime to avoid PED from distorting accuracy of EWT
Evaluate misleading info using practical applications
Strength of research on PED is has real life app
Led to practical uses for police officers eg highlights importance ensuring police gather information from witnesses immediately after crime and take care in how phrase questions to avoid PED and LQ distorting eye witnesses memory
A strength as consequences of inaccurate EWT due to PED can be serious therefore o research important implications for forensic psych
Makes difference real ppl by improving how legal system works and improving quality of EWT during court process
Evaluate misleading info using reliability as a strength
Many studies have found similar results eg Loftus conducted range of controlled experiments about EWT
As most research in labs have control over extraneous variables so research easy to replicate
Eg car crash experiment all ppts watched same video and received standardised instructions
Means researchers using identical procedures should get similar result s
Loftus conducted many studies and got same outcome that misleading info negatively affects EWT
Evaluate misleading info using the contradictory findings as a limitation
Yuille and Cutshalls research contradicts Loftus,s findings as found leading qs did not reduce accuracy of recall
Witnesses to real armed robbery of gun shop in Canada gave very accurate reports of crime 4 months after event despite being asked 2 leading questions
Suggests misleading info may have less influence on accuracy of real life EWT
Outline how anxiety affairs accuracy of EWT w Yerkes Dodsons curve
Emotional state of high anxiety could negatively affect how we store and encode info therefore affaects accuracy recall
Most lab studies show high anxiety leads to poor accuracy recall
Yerkes Dodson curve believes EWT most accurate w moderate anxiety
Outline weapon focus effect
Anxiety might reduce accuracy recall due to weapon focus effect (view that weapon in criminals hand distracts attention from other features due to anxiety it creates)
Has negative affect on ability recall important details
Outline aim and procedure of Johnson and Scott’s study on anxiety
To investigate whether high anxiety will affect accuracy recall
2 conditions (w weapon or wo weapon)
Low anxiety heard peaceful convo about office equipment and man emerges holding pen w greasy hands
High anxiety heard heated convo and breaking glass and man emerges w bloody knife
DV is no correct identifications of man from 50 photographs
Outline findings and conclusions of Johnson and Scott’s study
Low anxiety 49% able accurately identify man w pen
High anxiety memory recall worse only 33%
Conc is weapon distracted attention from person holding it
Explains why EWTs poor for violent crimes w weapons where anxiety is heightened
Outline Loftus and Burns study into anxiety
Proc is lab study, ppts watched film of simulated robbery
Some watch non violent version and some watch violent version where boy is shot in the head
Find is when questioned after, those in non violent condition recalled sig more details than violent condition
Conc is the shock of event had heightened arousal and therefore disrupted memory storage of details before and after violent scene
Evaluate anxiety on EWT using research lacks validity argument
Limitation research often criticised for being artificial eg video of robbery not same as real incident
Cannot reliably create real levels of anxiety experienced by real eyewitnesses in a lab for practical and ethical reasons eg not as unexpected / emotional as real life
Real life crimes have unexpected and tense atmosphere so are recalled different to in a lab
Furthermore, Foster et al found if ppts thought watching real life real life robbery important to real trial, their identification of robber much more accurate than if not
Therefore findings from research in controlled lab settings may lack ecological validity
This undermines findings that anxiety leads to inaccurate memory recall
Evaluate anxiety using the surprise not anxiety point
Pickle criticises research on anxiety and EWT suggesting reduced accuracy recall caused by weapon focus effect could be due to surprise not anxiety
Ppts watched theif enter hairdressers carrying scissors, handgun, wallet or whole raw chicken
Found EWT poorer in high surprise conditions
Suggest weapon focus effect may be due to surprise or unusualness rather than anxiety, therefore questions internal validity of research such as Johnson and Scott’s as may not be measuring effect of anxiety on accuracy of EWt at all
Evaluate anxiety using contradictory evidence as a limitation
Research criticised for not reflecting real life EWT
Christian and Hubinette did natural experiment which found emotional arousal may enhance accuracy of memory
Questioned 110 real witnesses to 22 real bank robberies and found witnesses threatened / had high anxiety had more accurate recall than onlookers (less emotionally aroused)
Concluded ppl good remembering highly stressful events in real life rather than artificial surroundings (especially victims of violent crimes)
A limitation as casts doubt on Yerkes Dodson curve hypothesis as those w high anxiety should have less accurate recall
Evaluate anxiety using limitation of ethical issues of research
Major issue for psychologists studying anxiety and EWT is cannot induce unnecessary psychological harm and need informed consent
However with EWT anxiety important variable so unless occurs naturally methods used to do this eg violent films may cause mild harm especially to children
Means ethically research questionable
However if psychologists don’t create anxiety findings unlikely to be valid
Research must subject to cost benefit analysis
Outline Context reinstatement
Interviewee is returned in mind to situation/ context when event occurred
Interviewer encourages them to mentally recreate environment (weather, lighting, smells, ppl nearby) and how they were feeling at time
Outline report everything
Report every detail about event that can recall even if seems trivial or irrelevant
Do not edit anything out
Outline recall from changed perspective
Mentally recreate situation from other ppls perspective eg describe incident from viewpoint of other witness
Outline recall in reverse order
Interviewer encourages interviewee describe event in reverse order / start w most memorable moment and work backwards from that point
Why does context reinstatement work?
If mental consistency between actual incident and recreated situation, increased likeliness witness will remember more detail and be more accurate in recall
Appropriate contextual and emotional cues help them retrieve memories (context and state dependant forgetting)
