If eye witness testimony is so unreliable, according to Elizabeth Loftus, how is
it that police still regularly interview WITNESSES when investigating a crime? How
come eye witnesses are still brought into the court room to share their recollections with
judge and jury? ***
Historically – and we’re talking pretty recent history here – police would ask a
witness questions in such a way that the witness was there only to confirm or deny information
that the police already thought they knew. The interviewer led the interview. The interviewee
spoke when given permission to do so. The “standard police interview”,
as it’s now referred to in the literature, often follows a structured checklist and witnesses are
discouraged from adding extra information. “Was the witness black or white?”, “Was the victim a
man or a lady?” – Answer the question. You can see why the quality of testimonies was so poor.
It makes me think of one of my favourite quotes, from the Ancient Greek stoic, Epictetus:
it is impossible to learn what you think you already know. Such is the weakness of the
standard police interview. So, in the 1980s,
a new style of forensic interviewing was created, called the Cognitive Interview.
Cognitive Psychology was enjoying a hey day at the time and even the police wanted in.
The Cognitive Interview technique was invented by Geiselman (et al., 1984) and refined by
Fisher (et al., 1987), with the purpose of using their knowledge of how memory works
and applying that to the interview process. The Cognitive Interview has four distinct
retrieval techniques at its core: 1. Re-establishing the context; by mentally
recreating the physical and psychological environment of the original situation.
What was the weather like? What had you been doing earlier in the day? How were you feeling?
What objects were around in the area? 2. Reporting everything, however minor;
because memories are connected to each other. Retrieving apparently
meaningless or trivial details may be the key to
recalling something particularly important. 3. Recalling the events in a different order;
As our memories are heavily influenced by schemas, the Cognitive Interview aims to
shake things up a bit to minimise the influence of our general expectations
on the recollection of a specific event. 4. Changing perspective; Again
attempting to disrupt the influence of schemas, the Cognitive Interview challenges the witness
to retell the run of events as someone else would have seen it from a different viewpoint.
Only after this extensive free-recall process will the witness be asked the more
traditional detail-centric questions, such as the suspect’s visual appearance.
The Cognitive Interview relies on the principles of Encoding Specificity
and has been found to increase the amount of correct information witnesses recall,
without a corresponding increase in false recollections (Gwyer and Clifford, 1997) – so,
people remember more overall, and the extra stuff tends to be more of the good stuff.
Geiselman (et al., 1984) found that witnesses are able to recall 35% more information using
the Cognitive Interview compared to a control group who were just instructed to remember as
much information as possible. And Mello and Fisher (1996) found that the technique is
especially effective in improving recall in older populations compared with younger witnesses.
However, whilst it appears that the Cognitive Interview is an improvement on the standard
police interview, it’s not altogether clear which elements of the technique
are responsible for the difference. Memon and Yarmey (1999) had participants
recall a staged kidnap scenario, comparing a standard interview with a version of the Cognitive
Interview that only used the context reinstatement and change of order stages. They conclude that a
standard interview that incorporates the social elements of the Cognitive Interview may be just as
effective as the full Cognitive Interview set up. Given that even Psychologists can’t agree,
and police forces are locally managed with differing policies and practices, the resulting
situation is one with many variations of the Cognitive Interview. This can make it challenging
to assess its reliability in the field because localised police forces have adopted a pick ‘n’
mix approach to the technique…. And everyone has their own idea of the best pick ‘n’ mix.