Reliability of eye-witness testimony

Created by: Francesca C
Created on: 12-05-19 11:36


	Reliability of eye-witness testimony
	Advantages Eye-witnesses are not reliable: Post-event information: Loftus & Palmer 1974, info suggested after the event became incorportated into the original memory. Loftus & Zanni 1975 also demonstrated the effects of post-event info. Found that 7% of those asked 'did you see a broken headlight' reported seeing one, whereas 17% of those asked 'did you see the broken headlight', reported seeing a headlight. The post event info was the word 'a' or 'the'. This research clearly demonstrates that even subtle changes in the wording used in questions can influence the recollection of the participant. This suggests that whenever a witness is questioned, either by the police, lawmakers, friends etc, their recollection of the actual event may be distorted. Crimes are emotive experiences: eye-witness may not be reliable because the crimes they witness are unexpected and emotionally traumatising. Freud argued that extremely painful or threatening memories are forced into the unconscious. This process, repression is an ego-defence mechanism. Nowadays, psychologists might call this 'motivated forgetting' but in either form perhaps eye-witnesses are not reliable because this memory of the crime is too traumatising. Child witnesses are not reliable - children as eye-witnesses are often regarded as unreliable because they are prone to fantasy and their memories may be especially affected by the suggestions made by others. Therefore, researchers have been interested in finding out if children are accurate eye-witnesses e.g. when identifying a perpetrator from a lineup. Lineups do not always include the target individual because otherwise a suspect could be selected because he/she fits an erronous description. Therefore eye-witnesses are now often told that the line-up may or may not include the target. A meta-analysis by Pozzulo and Lindsay 1998 drew data from a number of studies that between them had tested over 2,000 participants. The researchers found that children under the age of 5 were less likely than older children or adults to make correct indentifications when the target was present. Children aged 5-13 years did not differ significantly from adults in the target-present condition but were more likely to make a choice (inevitably wrong) in the target absent condition. It was thought that this was due to children being more sensitive about doing what they are asked to do, they feel they can't say no and have to give some answer, a false positive. Memory is reconstructive: Schemas are used to help us process info quickly. 1 drawback with schemas is that the info already held in our schemas may distort our memory of an event. In your criminal schema you will have an expectation of what a criminal will look like. These expectations may be derived from news reports, movies and tv programmes. When we later have to recall this info, these expectations may have become incorporated into our memory, inaccurate recall. Yarmey 1993 asked 240 students to look at videos of 30 unknown males and classify them as good or bad guys. There was high agreement amongst the participants suggesting that there is similarity in the info stored in the bad guy and good guy schemas. In the same way any preconceived ideas about the facial features of criminals may influence us when making decisions on suspects in a lineup or a photo array. This suggests that eye-witnesses may not select the actual criminal but the individual who looks most like a criminal.	Disadvantages Post-event info: eye witness research is misleading as it tends to focus on details that are tricky for us to estimate or details that are not central to the incident and thus may be more susceptible to corruption. Not all research suggests that post-event info is misleading. Loftus 1979b showed participants slides of a man stealing a large, bright red purse from a woman's bag. The participants were later exposed to info containing subtle errors or a more obvious one, purporting that the purse was brown. Although participants were often wrong about 'peripheral' items, 98% of the participants correctly remembered the purse they had seen was red. This suggests that eye-witness recollection for central or key details may be more resistant to distortion from post-event info than previously suggested. Crimes are emotive experiences: some psychologists believe that when we experience events which are very emotionally shocking and or which hold personal siginificance we create a particularly accurate and long lasting memory -flashbulb memory. There is evidence that the hormones associated with emotion, such as adrenaline, may enhance the storage of memories (Cahill and McGaugh 1995). This suggests that the emotion surrounding a crime may actually lead to more, rather than less, reliable memories. Child witnesses are reliable: Davies et al. 1989 reviewed the literature discussing children used as witnesses and came to some interesting conclusions. Children 6-7 and 10-11 are fairly accurate in their memories of an event, they do not usually 'make things up', do not deliberately lie when giving testimony. Their memory for important details is not significantly altered by adult suggestion after the event. These conclusions challenge many claims made by other researchers. Is it fair to claim child eye-witnesses are unreliable when much of the research uses adults as the 'target' individual? Anastasi and Rhodes 2006 found that all age groups are most accurate when recognising an offender from their own age group. This may mean that if the child witnesses had observed children committing staged crimes, perhaps they would be more reliable with identification. Memory may be reconstructive, but not unreliable: In many crimes eye witnesses know the perpetrator of the crime and don't need to refer to their schemas. RapeCrisis reports that 90% of rapists are known to their victims. This means that the eye-witness' ability to identify the assailant is likely to be very reliable, even when the crimes themselves are incredibly traumatic. Yuille and Cutshall, when research is conducted with eye-witnesses to real life crimes rather than lab based crimes, their accuracy is much higher than that suggested by lab based research. If memory was reconstructive you would have expected the eye witness recollections to have faded over time and to have been susceptible to leading questions, however, this was not the case in Yuille and Cutshall's research.
	Evaluation Ethical, Social and Economical Implications: Exonerated describes people convinted of a crime, but are later found to be innocent. Huff et al 1986 reported that nearly 60% of 500 mainly American cases of wrongful convictions involved eye witness identification errors. This suggests that too much reliance on EWT has major ethical implications. Dangers inherent in becoming too secptical of such evidence. Green 1990 reports that when mock juries were asked to make decisions about the guilt or innocence of a perpetrator based on EWT some jurors mentioned their knowledge of mis-identification mistakes. They knew about such mistakes from items on the news and this knowledge made them more specptical about the testimony of eye-witnesses. As eye-witnesses are a major source of info in any crime scene it is important to pay some attention to the evedince. A balance can be struck. In the UK there are safeguards that are built in to the Justice System. The Police and Criminal Evidence Act introduced in 1984 revised 1995, offered a code of practice that needs to be adhered to with regard to the conduct of identification attempts. However, it is still permissable to secure a conviction on the uncorroborated evidence of a single eye-witness. Unreliable EWT - retrials and compensation to those wrongly convicted. The economic costs of crime in the UK are vast. Recent estimates indicated about £124 billion per year (Instititue for Economics and Peace 2013); this equates to 7.7% of the UKs GDP. However, perhaps the biggest implication is not financial but the risk society faces as the real perpetrator of the crime remains free. Difficult for psychologists to definitively prove that eye-witnesses are or are not reliable. This area of research has been helpful in that it has led us to be more critical of the recollection of eye-witnesses. We have developed methods which mean eye-witness recollections is less susceptible to distortion, cognitive interviews (questioning that aims to increase the amount and accuracy of info recalled) and sequential lineups (eye-witnesses see people in the line up one by one rather than all at the same time). The increasing use of CCTV systems in the UK means that the unreliability of eye-witnesses is likely to become less of a problem in the future.

Reliability of eye-witness testimony

Advantages

Eye-witnesses are not reliable: Post-event information: Loftus & Palmer 1974, info suggested after the event became incorportated into the original memory. Loftus & Zanni 1975 also demonstrated the effects of post-event info. Found that 7% of those asked 'did you see a broken headlight' reported seeing one, whereas 17% of those asked 'did you see the broken headlight', reported seeing a headlight. The post event info was the word 'a' or 'the'. This research clearly demonstrates that even subtle changes in the wording used in questions can influence the recollection of the participant. This suggests that whenever a witness is questioned, either by the police, lawmakers, friends etc, their recollection of the actual event may be distorted.
Crimes are emotive experiences: eye-witness may not be reliable because the crimes they witness are unexpected and emotionally traumatising. Freud argued that extremely painful or threatening memories are forced into the unconscious. This process, repression is an ego-defence mechanism. Nowadays, psychologists might call this 'motivated forgetting' but in either form perhaps eye-witnesses are not reliable because this memory of the crime is too traumatising.
Child witnesses are not reliable - children as eye-witnesses are often regarded as unreliable because they are prone to fantasy and their memories may be especially affected by the suggestions made by others. Therefore, researchers have been interested in finding out if children are accurate eye-witnesses e.g. when identifying a perpetrator from a lineup.
Lineups do not always include the target individual because otherwise a suspect could be selected because he/she fits an erronous description. Therefore eye-witnesses are now often told that the line-up may or may not include the target. A meta-analysis by Pozzulo and Lindsay 1998 drew data from a number of studies that between them had tested over 2,000 participants. The researchers found that children under the age of 5 were less likely than older children or adults to make correct indentifications when the target was present. Children aged 5-13 years did not differ significantly from adults in the target-present condition but were more likely to make a choice (inevitably wrong) in the target absent condition. It was thought that this was due to children being more sensitive about doing what they are asked to do, they feel they can't say no and have to give some answer, a false positive.
Memory is reconstructive: Schemas are used to help us process info quickly. 1 drawback with schemas is that the info already held in our schemas may distort our memory of an event. In your criminal schema you will have an expectation of what a criminal will look like. These expectations may be derived from news reports, movies and tv programmes. When we later have to recall this info, these expectations may have become incorporated into our memory, inaccurate recall.
Yarmey 1993 asked 240 students to look at videos of 30 unknown males and classify them as good or bad guys. There was high agreement amongst the participants suggesting that there is similarity in the info stored in the bad guy and good guy schemas. In the same way any preconceived ideas about the facial features of criminals may influence us when making decisions on suspects in a lineup or a photo array. This suggests that eye-witnesses may not select the actual criminal but the individual who looks most like a criminal.

Disadvantages

Post-event info: eye witness research is misleading as it tends to focus on details that are tricky for us to estimate or details that are not central to the incident and thus may be more susceptible to corruption. Not all research suggests that post-event info is misleading. Loftus 1979b showed participants slides of a man stealing a large, bright red purse from a woman's bag. The participants were later exposed to info containing subtle errors or a more obvious one, purporting that the purse was brown. Although participants were often wrong about 'peripheral' items, 98% of the participants correctly remembered the purse they had seen was red. This suggests that eye-witness recollection for central or key details may be more resistant to distortion from post-event info than previously suggested.
Crimes are emotive experiences: some psychologists believe that when we experience events which are very emotionally shocking and or which hold personal siginificance we create a particularly accurate and long lasting memory -flashbulb memory. There is evidence that the hormones associated with emotion, such as adrenaline, may enhance the storage of memories (Cahill and McGaugh 1995). This suggests that the emotion surrounding a crime may actually lead to more, rather than less, reliable memories.
Child witnesses are reliable: Davies et al. 1989 reviewed the literature discussing children used as witnesses and came to some interesting conclusions. Children 6-7 and 10-11 are fairly accurate in their memories of an event, they do not usually 'make things up', do not deliberately lie when giving testimony. Their memory for important details is not significantly altered by adult suggestion after the event. These conclusions challenge many claims made by other researchers.
Is it fair to claim child eye-witnesses are unreliable when much of the research uses adults as the 'target' individual? Anastasi and Rhodes 2006 found that all age groups are most accurate when recognising an offender from their own age group. This may mean that if the child witnesses had observed children committing staged crimes, perhaps they would be more reliable with identification.
Memory may be reconstructive, but not unreliable: In many crimes eye witnesses know the perpetrator of the crime and don't need to refer to their schemas. RapeCrisis reports that 90% of rapists are known to their victims. This means that the eye-witness' ability to identify the assailant is likely to be very reliable, even when the crimes themselves are incredibly traumatic.
Yuille and Cutshall, when research is conducted with eye-witnesses to real life crimes rather than lab based crimes, their accuracy is much higher than that suggested by lab based research. If memory was reconstructive you would have expected the eye witness recollections to have faded over time and to have been susceptible to leading questions, however, this was not the case in Yuille and Cutshall's research.

Evaluation

Ethical, Social and Economical Implications: Exonerated describes people convinted of a crime, but are later found to be innocent. Huff et al 1986 reported that nearly 60% of 500 mainly American cases of wrongful convictions involved eye witness identification errors. This suggests that too much reliance on EWT has major ethical implications. Dangers inherent in becoming too secptical of such evidence. Green 1990 reports that when mock juries were asked to make decisions about the guilt or innocence of a perpetrator based on EWT some jurors mentioned their knowledge of mis-identification mistakes. They knew about such mistakes from items on the news and this knowledge made them more specptical about the testimony of eye-witnesses. As eye-witnesses are a major source of info in any crime scene it is important to pay some attention to the evedince. A balance can be struck. In the UK there are safeguards that are built in to the Justice System. The Police and Criminal Evidence Act introduced in 1984 revised 1995, offered a code of practice that needs to be adhered to with regard to the conduct of identification attempts. However, it is still permissable to secure a conviction on the uncorroborated evidence of a single eye-witness. Unreliable EWT - retrials and compensation to those wrongly convicted. The economic costs of crime in the UK are vast. Recent estimates indicated about £124 billion per year (Instititue for Economics and Peace 2013); this equates to 7.7% of the UKs GDP. However, perhaps the biggest implication is not financial but the risk society faces as the real perpetrator of the crime remains free. Difficult for psychologists to definitively prove that eye-witnesses are or are not reliable. This area of research has been helpful in that it has led us to be more critical of the recollection of eye-witnesses. We have developed methods which mean eye-witness recollections is less susceptible to distortion, cognitive interviews (questioning that aims to increase the amount and accuracy of info recalled) and sequential lineups (eye-witnesses see people in the line up one by one rather than all at the same time). The increasing use of CCTV systems in the UK means that the unreliability of eye-witnesses is likely to become less of a problem in the future.

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Reliability of eye-witness testimony