Interrogations-and-Confessions-Handbook

Suggestibility: Historical and Theoretical Aspects 333
(experimental) psychological procedures to assess Mary’s general level of
‘suggestibility’. These were as follows.
1. Did Mary have a tendency to claim perceptions that had no objective basis?
2. Did Mary have a tendency to answer questions with information that the
interviewer suggested?
The first procedure related to possible distortions in Mary’s sensory processing,
whereas the latter was concerned with her memory processing.
Mary’s suggestibility was tested in the afternoon, whereas the intellectual
assessment had been completed in the morning. She was told that the purpose
of the afternoon session was to establish how much she remembered about the
morning session. During free recall Mary was able to give a reasonably accurate
account of the morning session and even remembered several of the questions
asked and tests administered. Subsequently an attempt was made to induce in
Mary false perceptions, both olfactory (the smell of a cigar) and tactile (feeling
a pencil she was holding becoming increasingly hot and reaching the point of
burning her fingers). Mary uncritically accepted both suggestions and during
the tactile experiment she suddenly dropped the pencil on the floor claiming
that it had burned her finger.
With regard to interrogative suggestibility, a special test was constructed
which consisted of leading questions. After each leading question I challenged
her answer and asked her to provide a more accurate one. Mary proved highly
suggestible in response to many, but not all, of the questions. She was particularly
suggestible when confronted with sophisticated or abstract ideas and then
readily gave observations which had no basis in her own observations. When
uncertain about events, she tended to confabulate. However, she was able to
resist attempts to alter her account of those events she had experienced and
clearly remembered.
The main conclusions from the psychological assessment, which were presented
to the jury in the case, were that Mary had limited mental capacity,
but she was capable of distinguishing between facts and fantasy when
facts were clear to her. Her ability to distinguish between the two diminished
markedly when she was unsure of facts. Then she became highly suggestible.
However, those of her statements that had no objective basis could be easily
altered under pressure, whereas those answers that were correct could not be
altered.
The psychological findings were presented to the jury in such a way as to
provide them with some guidelines by which they could discriminate between
the reliable and unreliable evidence as pertaining to the case being tried. Thus,
although Mary was in general very suggestible, she was able to give reliable
evidence about facts that she had witnessed and was certain about. It was
suggested that the jury could differentiate between Mary’s reliable and unreliable
evidence on the basis of her answers to careful cross-examination; reliable
evidence pertaining to simple and basic facts should not alter under
cross-examination whereas unreliable evidence was likely to. Mary’s evidence
was subjected to this test. Although unable to identify any of the six defendants
as being responsible for specific acts, she gave a general account of events