Are two interviews better than one? Eyewitness memory across repeated cognitive interviews

Eyewitnesses to a filmed event were interviewed twice using a Cognitive Interview to examine the effects of variations in delay between the repeated interviews (immediately & 2 days; immediately & 7 days; 7 & 9 days) and the identity of the interviewers (same or different across the two repeated interviews). Hypermnesia (an increase in total amount of information recalled in the repeated interview) occurred without any decrease in the overall accuracy. Reminiscence (the recall of new information in the repeated interview) was also found in all conditions but was least apparent in the longest delay condition, and came with little cost to the overall accuracy of information gathered. The number of errors, increased across the interviews, but the relative accuracy of participants’ responses was unaffected. However, when accuracy was calculated based on all unique details provided across both interviews and compared to the accuracy of recall in just the first interview it was found to be slightly lower. The identity of the interviewer (whether the same or different across interviews) had no effects on the number of correct details. There was an increase in recall of new details with little cost to the overall accuracy of information gathered. Importantly, these results suggest that witnesses are unlikely to report everything they remember during a single Cognitive Interview, however exhaustive, and a second opportunity to recall information about the events in question may provide investigators with additional information

Distinguishing truthful from invented accounts using reality monitoring criteria

Purpose. Previous research has suggested that true and invented memories can be distinguished between using the reality monitoring criteria. Two different coding schemes were used to examine the correct classification of reports as truthful or deceptive on the basis of individual reality-monitoring (RM) criteria. Method. Drawing upon the RM framework the present experiment examined transcripts of verbal accounts of eyewitnesses to a staged event or made up details about the incident. The statements were elicited during a face-to-face cognitive interview (CI) and were analysed by coders trained in the identification of criteria indicative of self-experienced and invented accounts (referred to here as Version 1) and a similar coding method (referred to here as Version 2). Results. A distinction was made between 'external memories' (affective, perceptual, and contextual details) and 'internal' memories (cognitive operations). For Version 1, the results indicated a higher number of contextual and external details in the descriptions of experienced events and as is commonly found in the deception literature, truthful accounts were longer. For Version 2, temporal and auditory details were more frequent in true accounts. Contrary to prediction, there were also more references to cognitive operations in true accounts. Conclusions. Any forensic application of RM should consider how external factors (characteristics of the event, motivation to deceive, and questioning style) influence the presence of RM criteria. © 2010 The British Psychological Society