Interrogations-and-Confessions-Handbook

354 A Psychology of Interrogations and Confessions
Schooler and Loftus review in some detail the different components that
make up the model and its theoretical implications. They conclude that the
model
. . . represents a formidable attempt to make sense of a multi-faceted phenomenon.
The emphasis on the role of individual differences in interrogative suggestibility
complements the more experimental approach to the influence of post-event suggestions.
For example, experimental studies of post-event suggestions have usually
ignored the ways in which various personality variables may influence suggestibility...Atthesame
time the individual differences approach is relatively devoid of
detail regarding the precise cognitive mechanisms that may mediate the incorporation
of post-event suggestions. Throughout their discussion, Gudjonsson and
Clark hint at plausible mechanisms without explicitly describing them (p. 107).
Schooler and Loftus then proceed by discussing how Gudjonsson and Clark
could enrich their model by considering some of the central cognitive mechanisms,
such as ‘discrepancy detection’, that experimental research has identified
as mediating suggestibility. The importance of the principle of discrepancy
detection is that it helps to explain the process whereby people accept and integrate
inconsistent information into their memory (see e.g. Tousignant, Hall &
Loftus, 1986). According to this principle,
Recollections are most likely to change if a person does not immediately detect
discrepancies between post-event suggestions and memory for the original event
(Schooler and Loftus, 1986, pp. 107–108).
Discrepancy detection is assumed to be affected by two factors: (i) ‘the strength
of the original information in memory’ and (ii) ‘the manner in which the postevent
suggestion is influenced’ (p. 108).
Studies providing evidence for the influence of memory on discrepancy detection
have manipulated the interval between viewing the event and subsequent
suggestions being offered (Hertel, Cosden & Johnson, 1980; Loftus, Miller &
Burns, 1978). The results from these studies indicate that subjects are more
likely to incorporate misleading suggestions into their recollection when there
is a long interval between viewing the original event and the presentation of
post-event suggestions. Schooler and Loftus argue that one interpretation is
that the more memory deteriorates over time, the less subjects are able to
detect discrepancies between what they observed and what is subsequently erroneously
suggested to them. This implies that post-event suggestions are least
likely to impair discrepancy detection when encountered very close to viewing
the original event.
According to Schooler and Loftus, studies that have varied the sentence construction
of misleading suggestions provide evidence that discrepancy detection
is influenced by the manner in which the post-event suggestion is presented.
For example, Loftus (1981) found that explicitly directing subjects’ attention
to the misleading information made them more willing or able to scrutinize
their memories and detect discrepancies. Similarly, Greene, Flynn and Loftus
(1982) advised subjects, prior to their reading a narrative containing misleading