eye witnesses testimony (EWT)☑️

factors affecting the accuracy of EWT

misleading information

-police may direct witness using leading questions to give a particular answer through wording; usually arises with eye witness testimonies.

-procedure- loftus and palmer (1974) 45 student p’s to watch car crash film clips questioned on what they had seen. the question wording was manipulated; for example, some p’s were asked how fast the cars were going when they "smashed" into each other, while others were asked same question using the word "hit." this subtle change in wording significantly affected the p’s speed estimates, demonstrating how easily memory can be influenced by external factors.

findings

findings- the mean estimate speed for ‘contacted’ was 31.8mph, however for 'smashed', the mean estimate was at 40.5 mph, illustrating the impact of language on memory recall; leading question biased the eyewitness’ event recall.

why leading questions affect EWT

-response-bias explanation: wording has no real effect on memories, just influences how they answer their recollections. implies witnesses may adjust their memories to align with the expectations set by question phrasing, leading to inaccuracies in their testimonies. (‘smashed’ encourages them to choose a higher speed estimate while a neutral term like 'hit' would likely result in a more conservative estimate, demonstrating how subtle variations in language can shape a witness's perception of an event).

research on post-event discussion

procedure- gabbet et al (2003) studied p’s in pairs. each watched a video of the same crime from different angles; one could see elements of the event that the other could not. both then discussed what they had seen before individually completing a recall test

findings- 71% of p’s recalled aspects of the events they did not see in the video but had picked up in the discussion. control group with no discussion was 0%, showing evidence of memory conformity (NSI), and memory contamination (when eyewitnesses combine (mis)information from other witnesses)

why does post-event discussion affects EWT?

-memory contamination: when co-witnesses to a crime discuss their recollection of events, their EWT become altered or distorted from combining (mis)information from other witnesses to their own memory.

-memory conformity: where witnesses alter their memories to match others due to ISI or NSI, further complicating EWT. unlike memory contamination, the actual memory is unchanged.

evaluation of factors affecting accuracy of EWT (misleading information)

strengths

-high external validity: research has important practical uses in the criminal justice system - loftus (1975) showed leading questions can affect memory and aided development of the cognitive interview, improving the legal system and protecting the innocent of faulty convictions

counterpoint: loftus and palmers p’s watched film clips in a lab - very different from witnessing a real event (less stressful). foster et al. (1994) states p’s responses don’t matter in the same way (less motivated to be accurate), suggesting researchers are too pessimistic, and that EWT may be more dependable than suggested.

evaluation of factors affecting accuracy of EWT (misleading information)

limitations

-evidence against substitution: sutherland and hayne (2001) showed p’s a video and questioned with misleading questions. recall was more accurate for central details than peripheral ones - presumably because attention was more focused on central details so the memories were more resistant to misleading info ∴ an outcome not predicted by the substitution explanation.

-evidence that post-event discussion actually alters EWT: skagerberg and wright (2008) showed partnered p’s variant film clips (difference was hair colour). the findings were often a blend, not just one p’s answer, suggesting memory contamination is more prominent than memory conformity.

factors affecting EWT accuracy (anxiety)

negative affect on recall (weapon focus)

-anxiety affects psychological arousal, preventing attention to important cues, so recall is worse

procedure: johnson and scott (1976) p’s seated in a waiting room (the low-anxiety condition) and heard a casual conversation in the next room, then saw a man walk past carrying a pen with grease on his hands.

other participants heard a heated argument, accompanied by the sound of breaking glass. a man walked out the room holding a blood covered knife (the high-anxiety condition)

findings

the p’s later picked out the man from a set of 50 photos, 49% who had seen the pen-carrying man were able to identify him, however 33% were able to identify the man holding the blood-covered knife.

tunnel theory of memory: people have enhanced memory for central events; weapon focus as a result of anxiety can have this effect.

anxiety having a positive effect on recall

-the fight or flight response, physiological arousal the body, may improve memory for the event by improving cue awareness.

procedure: yullie and cutshall (1986) conducted study of an actual shooting in a bodega. 13/21 witnesses took part in the study five months post-incident. accuracy was determined by the number of details reported in each account, and asked to rank their fear on a scale and whether they had had emotional problems since.

findings and conclusions

-witness were very accurate in their accounts, there was little change in the amount recalled; the p’s who reported highest stress levels were most accurate, suggesting anxiety doesn’t have a detrimental effect on accuracy of eyewitness memory in a real world context, and could even enhance it.

evaluation of factors affecting EWT accuracy (anxiety)

strengths

-countering evidence of anxiety having a negative effect on recall accuracy. valentine and mesout (2009) found negative effects on recall. the researchers used an objective measure (heart rate) to divide p’s into high and low anxiety groups; significant difference. suggests anxiety has a negative effect on the immediate EWT of a stressful event.

-evidence suggesting positive effects: christianson and hubinette (1993) interviews 58 witnesses to actual robberies; workers and bystanders. the direct witnesses (workers) had more accurate recall than bystanders. suggests, from findings from actual crimes, anxiety doesn’t reduce accuracy of recall for EWT

evaluation of factors affecting EWT accuracy (anxiety)

limitations

johnson and scott may not have tested anxiety; reason for p’s focusing on weapon could have been due to surprise rather than fear. pickel (1998) conducted an experiment using scissors, a handgun and a wallet or a raw chicken as the handheld item in a hairdressing salon video. EWT was significantly poorer in high unusualness conditions, suggesting weapon focus effect is due to unusualness rather than anxiety/ threat and tells us nothing about the effects of anxiety on EWT

improving the accuracy of EWT - cognitive interview

-developed by fisher and geiselman (1992); argued EWT could be improved if police used better interviewing techniques based on psychological insights.

4 main techniques used:

1. report everything

2. reinstate the context

3. reverse the order

4. change perspective

1- report everything

-encourage witness to include every detail of the event even if it seems irrelevant and the witness doesn’t feel confident about the accuracy as seemingly trivial details may be important or trigger other memories

2- reinstate the context

-witness should mentally return to original crime scene, imagining the environment (weather, senses and their emotions at the time) for context-dependant forgetting

3- reverse the order

-events should be recalled in a different order from original sequence, out of chronological order to prevent people reporting their expectations of how event happened rather than reporting the actual events + prevents dishonest accounts (harder to produce an untruthful account reversed)

4- change perspective

-witnesses should recall the incident from the perspective of others. (eg of other witnesses, victim or perpetrators)

-done to disrupt expectations and disrupt the effect of schema on recall (contrast between what would have happened vs what actually happened

enhanced congnituve interview (ECI)

fisher et al. (1987) developed additional elements of the CI to focus on the social dynamic of the interaction (eg interviewer needs to know when to establish eye contact and when to relinquish it)

-ECI also includes ideas such as reducing eye witness anxiety, minimising distractions, getting the witness to speak slowly and asking open-ended questions

evaluation of improving accuracy of EWT - cognitive interview

strengths

-evidence that it works: meta-analysis by gunter kohnken et al. (1999), combined data from 55 CI and ECI comparison studies with a standard police interview. the CI gave 41% increase in accurate information, showing CI is effective to recall memory information that is available but not immediately accessible

counterpoint: kohken et al found increase in amount of inaccurate information recalled by p’s (more with ECI). they may sacrifice EWT quality in favour of quantity, so officers should treat eyewitness evidence with caution.

evaluation of improving accuracy of EWT - cognitive interview

limitations

-not all elements are equally effective or useful. milne and bull (2002) found each four techniques used alone produced more information but using a combination of first two steps produces better recall than any other combination ∴ casting doubt in overall credibility of CI

-police officers may be reluctant to useCI as it’s more time consuming and requires more training. (eg more time needed to establish rapport with eye witnesses and allow them to relax) many forces don’t have the resources for this (kebbell and wagstaff 1997) - suggests it’s not a realistic method.