Interrogations-and-Confessions-Handbook

180 A Psychology of Interrogations and Confessions
A confession that contains an apparently detailed special knowledge may
prove to be false (see, for example, Chapter 20). Special knowledge about a
crime can be obtained and contaminated through a variety of sources, including
the following.
1. The media.
2. The police.
3. Crime scene visits.
4. Crime scene material, such as photographs.
5. A third party (i.e. being told about it by the real perpetrator).
Any of the above modes of communication can contaminate the original knowledge
the person had about the crime, making it appear as if he is providing
knowledge that only the real perpetrator should possess. The best special
knowledge is that which is only known to the real perpetrator (e.g. where an
undiscovered body or murder weapon has been hidden). Once the police are
in possession of that special knowledge, the possibility of it being communicated
to the suspect during custodial confinement and interrogation may be
difficult to rule out. Audio or video recording of all interrogations can be important
to rule out such contamination, although even this procedure may not be
foolproof.
As will be shown in Chapter 18, even if the suspect reveals no special
knowledge, and appears to be unfamiliar with the crime, he may still be
convicted on the basis of that confession alone (see the case of Peter Fell in
Chapter 18).
The Discovery of a False Confession
When a false confession occurs, it may be discovered by different means, including
one or more of the following.
1. Discovery that no crime was committed (e.g. an alleged murder victim turns
up alive—see for example, Leo & Ofshe, 1998a; The Earl of Birkenhead,
1938).
2. New forensic evidence, including improved DNA testing capabilities
(Gudjonsson & MacKeith, 1994; Scheck, Neufeld & Dwyer, 2000;
Wambaugh, 1989).
3. New alibi evidence (see Chapter 17 with reference to Gerry Conlan).
4. Newly discovered medical evidence, which would have made it impossible
for the person to have committed the crime (see e.g. Rose, Panter &
Wilkinson, 1998). There may also be evidence that proves that the defendant
could not have committed the crime, because he was in police custody
or prison at the time of the offence (Leo & Ofshe, 1998a).
5. Somebody else confesses and is convicted of the offence (Cassell, 1999;
Gudjonsson & MacKeith, 1990; Leo & Ofshe, 1998a).
6. Psychological and psychiatric evidence that casts serious doubts on the
veracity of the confession (Gudjonsson, 1995d; Gudjonsson, Kopelman &
MacKeith; 1999; Gudjonsson & Lebegue, 1989;).