Interrogations-and-Confessions-Handbook

334 A Psychology of Interrogations and Confessions
which the jury found reliable. The outcome of the case was that five of the six
defendants were convicted on at least one charge.
The most important lesson from this case is that persons with moderate
learning disability may well be able to give reliable evidence pertaining to basic
facts, even when they are generally highly suggestible and prone to confabulation.
A detailed psychological assessment of the learning disabled person’s
strengths and limitations may be necessary in some cases in order to provide the
jury with information which helps them evaluate the reliability of the person’s
testimony.
The present case provides a model of how this can be achieved. Davies, Flin
and Baxter (1986) consider that an extension of the procedure pioneered in our
case could provide a useful innovation in the case of children’s testimonies.
There was an important legal distinction made in the present case between
Mary’s competence as a witness and the reliability of her evidence. The two
were dealt with as separate issues. Competence was decided by the judge on
the basis of Mary’s understanding of the concepts of truth, God and contempt
of court, whereas the issue of reliability, the judge decided, was for the jury to
decide upon.
Mary’s case provided a conceptual framework for assessing the reliability of
evidence by way of psychological procedures. It resulted in the development of
a standardized psychological test for measuring interrogative suggestibility
(Gudjonsson, 1983, 1984a), which formed the basis for the theoretical model of
Gudjonsson and Clark (1986).
In this chapter the theoretical work that has been carried out into interrogative
suggestibility will be reviewed in some detail. I will argue that it is a
special type of suggestibility and it bears little resemblance to traditional classifications
of suggestibility, such as that commonly associated with hypnosis.
I shall endeavour to explain how precisely it differs from other types of suggestibility
and what the implications are. Until the early 1980s interrogative
suggestibility had been a neglected area of research and much of the review
literature into suggestion and suggestibility have failed to specifically mention
this type of suggestibility.
THEORETICAL APPROACHES
The are two main theoretical approaches to interrogative suggestibility.
Schooler and Loftus (1986, 1993) refer to these as the ‘individual differences
approach’ and the ‘experimental approach’. According to these authors, the
first approach is best illustrated by my own work (Gudjonsson, 1983, 1984a),
which was integrated into a detailed model (Gudjonsson & Clark (1986). The
model has specific domains of applicability to police interrogation and views
suggestibility as being dependent upon the coping strategies people can generate
and implement when confronted with the uncertainty and expectations of
the interrogative situation. The emphasis of the model is on explaining individual
differences in interrogative suggestibility.
The ‘experimental approach’ is illustrated by the work of Loftus and her colleagues
(Loftus, 1979a, 1979b; Loftus, Miller & Burns, 1978; Schooler & Loftus,