Offender
Profiling Series: Vol 1
Interviewing and Deception
Edited by David Canter & Laurence Alison
(1999)
back to Interviewing
& Deception
Interviewing and Deception
Bryan Tully
Statement Validation
The major premise of statement analysis stems from
empirical evidence that the recall of real events differs noticeably
from fabricated accounts in (Undeutsch, 1954; Trankell, 1972; Wegner,
1989). Udo Undeutsch pioneered the technique of credibility assessment
to develop relatively precise, definable criteria, that may help discern
valid statements from artificial ones. This chapter outlines the original
"Undeutsch Hypothesis" (Undeutsch, 1954), highlighting its
complexities, limitations and its developments into Criteria Based Content
Analysis (CBCA), (Stellar and Kohnken, 1989). After much empirical testing
CBCA is generally considered the most systematised aspect of the overall
Statement Validity Analysis procedure.
This chapter looks at the development of credibility assessment, and
emphasises the difficulties apparent to researchers when evaluating
the technique. These include setting up of adequate field studies using
real cases, problems of cognitive and motivational issues affecting
the reliability of statements and the possible variations in the use
of the criteria available to statement analysis. Although often discredited
as being a relatively subjective technique, this chapter concludes that
statement analysis is a means of applying psychological knowledge, not
a conclusion generator in its own right.
Bryan Tully is
a Chartered Clinical, Occupational and Forensic Psychologist. He was
trained and worked in various NHS settings and was a Research Fellow
for the Police Foundation UK in the early 1980s. Following this he was
appointed Head of a newly created Psychology Unit for the Royal Hong
Kong Police Force. Through that appointment, Dr Tully developed his
interest and specialist knowledge of the problems and techniques for
obtaining reliable and robust testimony from vulnerable victims and
suspects in the legal system. He was trained in "Statement Validity
Assessment" by the original developer of this methodology, Professor
Udo Undeutsch of the University of Cologne. Since then he has met and
consulted with most of the internationally leading researchers in this
area. From the early 1990s Dr Tully has practised as an expert witness
Psychologist and he is one of the six members of the Psychologists at
Law Group based in London and Bristol. A major theme in many of the
legal cases undertaken in the question or questionability of credibility
of memory or reports, ranging from personal psychological injury claims
to disputed confessions and so called recovered memories of childhood
sexual abuse.
