factors effecting accuracy of eyewitness testimony~ misleading information Flashcards
eyewitness testimony definition
the ability of people to remember details of events, such as accidents and crimes, which they themselves have observed. accuracy EWT can be affected by factors such as anxiety and misleading information
misleading information definition
incorrect information given to an eyewitness usually after an event. it can take may forms, such as leading questions and post-event discussion between co-witness and/or other people
leading question definition
a question which because of they ways its phrased, suggests a certain answer
post-event discussion definition
occurs when there is more than one witness at an event. witnesses discuss what they have seen with the co-witness or with other people. this may influence accuracy of each witness’s recall of the event
when does post-event discussion occur
when there is more than one witness to an event
why is wording of question important for EWT
police questions may direct a witness to a particular answer
who did research on leading questions
Loftus and Palmer
when did Loftus and Palmer do research on leading questions
1974
Loftus and Palmer’s research on leading questions procedure
45 students watched film clips of car accidents and then asked questions about the accident. in the critical question (leading question) participants were asked how fast the cars were travelling. there were 5 groups and each was given a different critical verb in the question
Loftus and Palmer’s research on leading questions sample
45 students
Loftus and Palmer’s research on leading questions findings
when mean estimated speed was calculated for each group. the verb contacted resulted in estimated mean of 31.8mph and the verb smashed resulted in mean of 40.5mph. the leading question biased the eyewitness’s recall of an event
what were the 5 critical verbs used in Loftus and Palmer’s research on leading questions
-hit
-contacted
-bumped
-collided
-smashed
Loftus and Palmer’s research on leading questions conclusion
the leading question biased they eyewitnesses’s recall of an event
what are 2 explanations as to why leading questions affect EWT
-response-bias explanation
-substitution-explanation
why does response-bias explanation suggest leading questions affect EWT
suggests that the wording of the question has no real effect on the participants memories, but just influences ow they answer the question. for example when participant gets leading question using word ‘smashed’ they choose a higher estimated speed
why does substitution explanation
loftus and palmer conducted 2nd experiment in 1974 supporting substitution explanation. it proposes that the wording of a leading question who originally heard smashed were later more likely to report seeing broken glass (there was none) than those who heard hit. critical verb altered memory of incident
what is post-event discussion
eyewitnesses to crime discussing their experiences and memories with each other
who did research on post-event discussion
Gabbert et al
when did gabbert et al do research on post-event discussion
2003
Gabbert et al research on post-event discussion procedure
studied participants in pairs. each participants watched a video of the same crime but filmed from different points of view. this meant that each participant could see elements of the video the other could not, for example only one participant could see the title of a book being carried by a young women. both participants discussed what they had seen before individually completing a test of recall
Gabbert et al research on post-event discussion findings
71% mistakenly recalled aspects of event that they did not see in video but picked up in discussion. the control group where there was no discussion had 0%. this is evidence of memory conformity
what are the 2 explanations for why does post-event discussion effect EWT
-memory contamination
-memory conformity
what is the memory contamination explanation for post-event discussion affecting EWT
co-witnesses to a crime discuss with each other, their eyewitness testimonies may become altered or distorted. this is due to combining (mis)information from other witnesses with their own memories
what is the memory conformity explanation for post-event discussion affecting EWT
Gabbert et al concluded that witnesses often go along with each other either to wind social approval or because they believe the other witnesses are right and they are wrong, unlike with memory contamination, the actual memory is unchanged
strength of misleading information effecting accuracy of EWT- real-world application
-research into misleading information has important practical uses in criminal justice system
-consequences of inaccurate EWT can be serious Loftus (1975) believes leading questions can have a distorting effect on memory that police need to be careful about how they phrase questions. psychologists are sometimes asked to act as expert witnesses in court to explain limits of EWT to juries –> shows psychologists can help improve legal system, especially by protecting innocent people from faulty convictions based on unreliable EWT
limitation of misleading information effecting accuracy of EWT- counterpoint to real-world application
-practical implications of EWT may be affected by issues with research
-for example, Loftus and Palmer’s participants watched film clips in a lab which is very different from witnessing the real event. Foster et al (1994) points out what eyewitnesses remember in the real world has important consequences but participants responses do not so there is less motivation to be accurate –> suggests researchers such as Loftus are too pessimistic about effects of misleading information and EWT may be more dependable than many studies suggest
limitation of misleading information effecting accuracy of EWT- evidence against substitution
-limitation of substitution explanation is EWT is more accurate for some aspects than others
-Sutherland and Hayne (2001) showed participants a video clip. when participants were later asked misleading questions, their recall was more accurate for central details of the event than the peripheral ones, presumably the participants attention was focused on central features so memories were relatively resistant to misleading information –> suggests original memories for central details survived and were not distorted, an outcome not predicted by substitution explanation
limitation of misleading information effecting accuracy of EWT- challenging memory conformity
-limitation of memory conformity explanation is evidence post-event discussion alters EWT
-Skagerberg and Wright (2008) showed their participants film clips. there was one version where a muggers hair was dark brown and one where it was light brown. participants discussed the clip in pairs, each having seen different versions. they often did not report what they or their partner had seen but a bend –> suggests memory itself is distorted through contamination by misleading post-event discussion rather than result of memory conformity
evaluation of misleading information effecting accuracy of EWT- demand characteristics
s- lab studies have identified misleading information as a cause of inaccurate EWT, partly being able to control variables
l- Zaragoza and McCloskey (1989) argue that may answers given by participants in lab studies are due to demand characteristics. participants usually want to be helpful and not let researcher doesn’t. so they guess when they are asked a question they don’t know answer to
