Narrative plausibility: the impact of sequence and anchoring

The perceived plausibility of suspect narratives is hypothesised to be a product of more than logical evaluation. Aspects of the narrative’s internal structure, notably the extent to which it follows a canonical sequence, may influence judged plausibility. It may also be sensitive to external ‘anchors’ that activate relevant schema. To test these possibilities two suspect testimonies were created: one involving a possible homicide and the other a possible burglary. A second version of each of these statements was created in which the narrative clauses occurred in a different order to the canonical sequence elaborated by Stein and Glenn (1979). A further version of each of these four statements was also created to contain ‘criminal anchors’, of the form discussed by Wagenaar, van Koppen and Crombag (1993), i.e.: statements that reflected commonly held beliefs about criminality. In the first study ten subjects each separately rated each of the eight narratives using a perceived plausibility scale developed from pilot work. ANOVA revealed that the addition of criminal anchors led to a significant decrease in perceived plausibility, but the effect of narrative sequencing was dependant on scenario (homicide or burglary). Ambiguities within Stein and Glenn’s model of narrative structure were identified, and new testimonies created. A second study with these new narratives (N=60) found support for the effect of narratives sequence as well as replicating the influence of criminal anchors. The implications for models of how people judge plausibility are discussed, as are the practical implications for legal contexts.