Eyewitness Testimony I Flashcards
justice system
- flow of processes
- human error is inevitable
weapon focus effect
- attention narrows on weapon (or any object pointed at you) and makes it harder to recall the face of the offender
witness reliability??
- we tend to recall on the basis of what we expect
- is persuasive but incredibly unreliable
- no reason to doubt a witnesses testimony therefor very persuasive
the innocent project statistics
- 337 DNA exonerations to date
- 14 average number of years served
- 140 real perpetrators were found
misidentification
- misidentification was the greatest contributing factor to wrongful convictions
- played a role in more than 70% of overturned convictions
validity
- that the testing instrument measures what it is meant to be measuring
- identification is valid when it is “made from the witness memory of the offender at the time of the event, and not on the basis of extraneous factors”
reliability
- that the results are consistent
- the identification of the accused would be reliable when the accused is consistently identified as the perpetrator of the crime
ecological validity
- the extent to which the findings of research are able to be generalisable to real-life settings
- university students do not represent the wider demographic because they typically come from a different socioeconomic background
memory
people fill in the gaps within their memory with what they think/expected happened
attributional bias
a cognitive bias that refers to the systematic errors made when people evaluate or try to find reasons for their own and others’ behaviours. People constantly make attributions—judgements and assumptions about why people behave in certain ways
schemas
- cognitive systems that help us organise and make sense of information
- because of the sheer volume of information we are exposed to we categorise information (e.g. animals, people, furniture)
- sometimes we develop faulty categories - called stereotypes
stereotypes
- generalisations about members of social groups
- resistant to new or inconsistent information
Allport & Postman (1947)
- showed participants a drawing of serval people on a train with several white people, one white man holding a razor, and one black man
- only the first person saw the drawing and then verbally described it from one participant to the next
- the final description of the drawing had changed to show the black man holding the razor
estimator and system variables
two variables that influence recall ability and accuracy
system variables
- system variables influence retrieval abilities
- e.g. line up instructions, methods of questioning witnesses
estimator variables:
the ability of a witness to accurately observe an event is influenced by the characteristics of the event itself
event factors
- lighting conditions
- takes about 15 seconds for our eyes to adjust from a sudden switch of light (e.g. dark to light)
- exposure time (duration of the event)
- the longer an event is observed the more accurate the memory will be
- frequency
- the more time someone is exposed to a stimulus, the more accurate the memory will be
- violence levels
- increased violence reduce recall and accuracy
witness factors
characteristics associated with the witness may influence the reliability of eyewitness memory
e. g.,
- alcohol and drugs impair the ability to encode information
- attention more likely to be focused on a weapon if present
- expectations
- expectations are biased that influences how we perceive environmental information;
momentary expectations
we see what we expect at the moment - we tend to see & hear what we expect to see and hear
cultural expectations
beliefs held by a large number of people within a given culture
expectations from past experience
we expect what we have previously experienced
personal prejudices
when watching a football game, people see their own team as victims of aggression rather than the initiators of aggression
experimental jury vs real
experimental jury get a summary (7~ pages) whereas real jury sit in on the trial - very different experiences
race & witnesses
- witnesses are more likely to identify someone from their own race than a different race
- witnesses find it difficult to ID someone from another race
perceptual expertise theory
we process features simultaneously when looking at those of our own race (e.g. nose and eyes at once) but individually in people of another race
social cognitive theory
- people process and encode other category-specific features (features available to all people in that racial group)
- people encode their own race features identify specific features (features that distinguish one person from another)
- e.g. seeing one race as all looking the same
