Factors affecting EWT Flashcards
What is eye witness testimony?
Evidence supplied by people who witness a specific event or crime, relying on only their memory.
The Devlin Committee (1976)
Analysed over 2000 identification parades in England and Wales during 1973, 45%/ of these led to a suspect in which led to 82% of them being convicted. In 350 cases, eyewitness identification was the only evidence of guilt and still 74% were convicted.
Cutler and Penrod (1995)
Point out that eyewitnesses can be 100% confident and 100% incorrect.
Wells et al (1998)
DNA evidence subsequently showed that none of the convicted criminals could have been the offender. This means it it believed that eye-witness testimony is the leading cause of false convictions.
What would the LTM say?
Encodes semantically so if the witness did not rehearse the scene with added meaning to it, then details may decay which leads to false EWT.
What would the STM say?
Can only hold 7 plus or minus 2 pieces of information so may not be able to remember everything unless specifically rehearsed.
Schemas and confabulation
Schemas fill in gaps as to what we believe was supposed to happen. For example, seeing a fist fight you might expect to see blood so say that there was blood at the scene.
Simplification
May have simplified the event to make it easier to remember which may mean that important details are forgotten.
Transformation
People may transform events into something that makes more sense to them and which is more common, so details are changed and are therefore, inaccurate.
Rationalisation
People may miss out parts of the story that are baffling such as someone doing something unusual which may have been a key piece of information.
Semantic memory
Memories need to have a meaning to them to be able to remember them effectively.
Episodic memory
Memories linked to time and concept so must have time and context references to make the input continuous to remember all details of the event.
What is post event information?
Information that the victim gains before the trial and after witnessing the crime which they then believe that they have seen.
What is the misinformation effect?
The tendency for post-event information to interfere with the memory of the original event.
Source monitoring error
Participants remember the misinformation but they do not remember where they heard it. It can happen when reality and fantasy is confused. e.g. Loftus’s study with Bugs Bunny.
