IGOR AREH, PETER UMEK
PERSONAL CHARACTERISTICS AND VALIDITY OF
EYEWITNESS TESTIMONY
If criminal investigators do not find any firm evidence and relevant witness of a
crime exists, a question about reliability of a witness is brought forward. Is it
possible to successfully assess a subject and predict the validity of an eyewitness
testimony? In an effort to come close to an answer we have been working on a
research project in which we try to explain connection between specific personal
characteristics and memory recall. We assume that it is possible to develop a model
which will help criminal investigators (psychologists) to predict, with some fair
certainty, suitability of an eyewitness.
Personal characteristics were measured by Eysenck's test of personality EPQ, with
which we searched for a correlation among personal traits and the validity of
witness memory recall.
Persons high on extroversion and low on neuroticism are more reliable witnesses.
Extrovert ones are oriented toward other people and more empathetic. Accuracy of
memory recall also depends on personal emotional stability. Thus subjects with
high neuroticism produce less accurate recall (higher proportion of added and
false details). Similar performance by subjects with high psychoticism was found.
They are less empathetic, less social and they care less about collaboration with in
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vestigators and performance in the experiment. They also showed a weak response
or low quantity of recalled data.
INTRODUCTION
A criminal justice system relies heavily on eyewitness reports for investigating and
prosecuting crimes. An incorrect or a completely false eyewitness testimony can have
negative or even fatal consequences, especially if it is the only piece of evidence
available. Psychologists and other scientists are trying to investigate various factors
related to the accuracy of eyewitness testimony. These factors include characteristics
of the eyewitness, of the witnessed event, of the testimony etc.
Research began in the 1970s and the findings were quite important. In spite of that, it was
not until 1990s that criminal justice personnel began to take these research results
seriously. This change in the attitude was partly due to the putting of DNA tests into
force. The research in the USA showed that among one hundred people who were
convicted prior to the advent of forensic DNA tests, approximately 75 % were victims of
mistaken eyewitness identification (Wells, 1998). Those results are not only a conse
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quence of memory imperfection. It is obvious that a behaviour expressed by a witness
has an important influence on police officers, investigators, members of a jury, judges
etc. (Ebbesen, 2000). Due to the fact that in most cases crimes do not include DNA-rich
biological traces, our reliance on eyewitness testimony has not been weakened.
Today's knowledge about problems connected with eyewitness testimony derives
form two sources: from the simulations made in the laboratory conditions and from
real-world observations. If we wish to understand the quality and quantity of eyewit
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ness testimony, we need to investigate real-world situations (Schacter, 1996). Never
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theless, in these situations it is often difficult to gather objective knowledge of the
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This item was translated into English by the source and not subject to subsequent editing. Views, opinions, and conclusions
are those of the author and do not imply endorsement, recommendation, or favor by the U.S. Government.