Interrogations-and-Confessions-Handbook

The Psychological Assessment 321
as any intellectual deficits. There is empirical evidence from American studies
that the majority of defendants with a history of learning disability do not receive
a pre-trial evaluation of their disability (Brown, Courtless & Silber, 1970;
McAfee & Gural, 1988). This means that only those with the most severe handicap
will be identified (Allen, 1966; Denkowski & Denkowski, 1985). Those who
are only mildly learning disabled are least likely to be identified, especially if
their social functioning seems relatively satisfactory (Gudjonsson et al., 1993).
At one extreme one may have an autistic individual, whose impaired social functioning
is a key feature, but whose intellectual functioning may be relatively
unimpaired (Happe, 1999). The police would probably identify the disability because
of the social deficits and the necessary safeguards provided in law would
be invoked. At the other extreme, which is undoubtedly much more common,
the police interview suspects and witnesses who are significantly impaired intellectually
but whose social functioning seems adequate and masks their true
intellectual deficits. Of course, there are also those cases where both intellectual
and social deficits are present, but the police nevertheless fail to identify or take
appropriate action (Gudjonsson, 1992a; Medford, Gudjonsson & Pearse, 2000).
In my experience the police often fail to identify persons with learning disability
and interview the suspect without an appropriate adult and a solicitor
being present. When the case goes to court a later pre-trial assessment may
reveal the disability and the self-incriminating confession may be ruled inadmissible
by the judge (see Chapter 10). Therefore, the failure of the police to
identify learning disability may prevent the suspect from exercising his or her
full rights during custodial interrogation. If the disability is still not identified
when the case goes to court then a miscarriage of justice may result. In other
words, the learning disability of the defendant, which may have significant
bearing on the reliability of the confession and the fairness of the proceedings,
cannot be taken into consideration by the judge and jury unless it has been
correctly identified. Therefore, identification of the disability during the early
part of the police investigation is crucial, for the defendant and the police.
Possibly the most common reason for the failure of police officers to identify
learning disability prior to or during custodial interrogation is that many
mildly disabled adults function quite well socially (Richardson, 1978). This
can disguise their more subtle disabilities. Another problem is that many
police officers appear unaware of how to identify suspects with mild learning
disability and why they may be vulnerable to giving unreliable information
during interrogation (Williamson, 1990). Even when police officers are presented
with unequivocal information about specific vulnerabilities (e.g. previous
medical history), many fail to identify the suspect as being ‘at risk’ (Medford,
Gudjonsson & Pearse, 2000; Pearse, 1991). In the Pearse (1991) study, the
younger officers were much poorer at identification than the older officers, which
indicates that maturity and experience are important for appreciating suspects’
vulnerabilities.
It is very important to realize that it is not just the police who commonly
fail to identify mild learning disability. I have come across numerous cases
where Prison Medical Officers and psychiatrists have grossly overestimated
the intellectual functioning of defendants: an error that could have resulted