Criminal

Criminal

1. Eye-witness testimony

   • Loftus and Palmer
     • Experiment 1
       • Used an opportunity sample of 45 students
       • Found the following estimates, smashed=40.8, collided=39.2, bumped=38.1, hit=34.0, contacted=31.8
       • Procedure= participants were shown clips of traffic accidents, safety films for drivers lasting between 5 and 30 seconds. Participants were divided into 5 groups of 9. They were asked a series of questions including the critical question 'how fast were the cars going why they ... into each other?" The IV was the verb the participant was given, the DV was the speed estimated given in miles per hour (mph)
       • Findings=partcicpants given the verb 'smashed' had the highest estimates of speed
       • Conclusion=information in the question can bias an individual's response and alter memories
       • Results of this study support the effect of post-event infromation
         • Memory can be influenced by post-event information (that information after an event might effect or distort the accounts of eye-witnesses) and leading questions. )
     • Experiment 2
       • The critical question appeared randomly within a longer interview
       • Procedure=150 participants were shown a 1 minute film that included a short scene of a car accident. 16 participants reported broken glass in the smashed condition, 7 in the hit condition, and 6 in the control group. 1 week later participants were questioned about their recall including a critical questions 'did you see ant broken glass?' No glass was actually included in the film clip. The IV was the wording of the questions.
         • Findings suggests that leading questions don't just bias the response but alters the memory of individuals and generates expectations
         • Results=participants in the smashed condition had the highest estimates of speed and were signifcantly more likely to report broken glass
     • GRAVE
       • Generalisabilty= Loftus and Palmer's study lacks generalisabilty as it unrepresentative
         • Which experiment is better in terms of generalisabilty?
           • Experiment 2 involved 150 participants and experiment 1 had 45 participants and so 2 has better generalisabiilty as more people means more of the population is represented
             • Both experiments are ethnocentric as they only used people from America
             • They are also all fairly young so may not have a fully developed understanding of driving speed
               • Counter-argument
                 • Memon suggested that young adult witnesses have a more accurate memory than older, especially if there is a delay between witnessing the delay and recall.
       • Reliabilty
         • Support
           • Loftus and Palmer's study has a standardised procedure making it high in internal reliability
             • They watched the same seven driver educating videos that were 5-30 seconds but they all watched them in a different order
             • Counter argument
               • Yuille and Cutshall found that leading questions aren't successful when the questions are about a traumatic event, both close to the memory and 4-5 months later. This means that Lotus and Palmer lack external reliability.
           • Loftus and Palmer's findings have been replicated in further studies on post-event information
           • What findings and conclusions does this replicate?
         • Against
           • Studies with real witnesses do not support Loftus and Palmer's findings suggesting problems with the reliability of this study
           • What aspect of their procedure might be flawed?
       • Application
         • Loftus and Palmer's findings have been crucial in reviewing the use of EWT in the legal system
           • The devlin report had several recommendations such as that the juries should not be convicted soleyl on the basis of the EWT
             • counter-argument
               • A real car crash is more likely to be remembered as you are likely to experience more emotions like anxiety, stress and fear and the study was only done on car crashes which are wildly different to murders
         • Why are the real world application of Loftus and Palmer's findings limited?
       • Validity
         • support
           • Loftus and Palmer's findings have high levels of internal validity
           • What controls did Loftus and Palmer put in place?
         • Against
           • Loftus and Palmer's study lacks external validity
             • The study was done in an laboratory so lacks ecological validty, less stressed in a lab compared to a real crash, people in a real crash/watching the crash are more likely to have their attention divided by other things going on then in a lab
               • Counter argument
                 • Mundane realism=reduced demans characteristics because the questionaire included many filler questions to hide the question they were actually interested in
           • What impact might anxiety have?
       • Ethics
         • Loftus and Palmer's study was ethical
           • Loftus and Palmer respected informed consent as all the participants were aware they were in the study and their identities were kept confidential
             • Counter-argument
               • However, if the participants were to have known the aims of the study then the study wouldn't have been accurate as they would have known what they were being studied on and may change how they react

2. Evaluate the use of ... in assessing EWT

   • Laboratory experiments
     • AO1
       • Standardised and controlled procedures
       • Done in an artificial environment
       • Control reduces extraneous variables
       • Researcher directly manipulates the IV
     • Strengths
       • Reduced chances of confounding variables or extraneous variables
       • Standardised procedures which improves the reliability
       • Easier to replicate so high internal reliability
     • Weakness
       • Lacks ecological validity as it's conduced under artificial condition and so can't be applied to real world
       • Might have demand characteristics as participants know they are in a study which lowers validity
     • Criminal
       • Loftus and Palmer meets the features of lab experiments as it was controlled in a lab and had standardised procedures such as them all watching 7 different videos and being given questionaires
       • Study was done in a lab so although it was standardised and controlled, it lacked real world application as if a car crash were to occur in real life than it would likely be more emotional and traumatic, and the study was used to deter the use of eye-witness testimonies but the study was on car crashes
       • As it is a lab study it is easily replicated which allows for higher reliability, but as it's in a lab the participants are aware they are apart of a study so may display demand characteristics which lowers the studies internal validity
   • Field experiments
     • AO1
       • Conducted in a natural real life environment
       • Extraneous variables are not controlled
       • Independent variable is manipulated by the experimenter
       • DV measured in the field
     • weakness
       • Less control of extraneous variables causes lower validity
       • May be ethical issue if participants aren't aware of being studied, informed consent and debriefing may not be possible
     • Strengths
       • Higher ecological validtiy as the study mirrors real life experiences and feels more like everyday life
       • Avoids demand characteristics and researcher bias as the participant are not usually aware of being studied
   • Case Studies
     • AO1
       • Retrospective=Only study the person after the event
       • Idiographic=only 1 participant/event
       • Naturally occurring independent variable
       • Collect qualitative and quantitative data
     • Strength
       • Able to collect both qualitative data and quantitative data so can find a balanced conclusion
     • Weaknesses
       • Lacks generalisability as only one person, hard to apply that to every human in the population
       • Retrospective, don't know what the person was like beforehand, correlation may not be causation