P A Granhag | Search PubMed

PubMed2001

Deception detection: interrogators' and observers' decoding of consecutive statements.

This study is an examination of two forensically important but previously neglected issues in interpersonal deception. First, which cues do lie catchers-who have access to repeated interrogations-pay attention to in order to detect deception? Second, do face-to-face interacting interrogators differ from noninteracting observers in terms of how they perceive a suspect? After watching a staged event, 24 suspects (12 liars and 12 truth tellers) were interrogated three times over a period of 11 days. After the final interrogation, the veracity of each suspect was assessed by his or her interrogator and by 6 observers who had watched the interrogations on video only. The results of the experiment showed that consistency over time was by far the most commonly used cue for justifying veracity judgments. Critically, the predictive accuracy for this cue was alarmingly low. As opposed to results from previous research, the interrogators used verbal cues to a significantly greater extent than did the observers. Furthermore, a probing effect was shown (i.e., probed suspects were perceived as significantly more honest than nonprobed suspects). Finally, limited support for a previously reported honesty effect was obtained (i.e., that interrogators perceive suspects to be more honest than do observers).

Cues↗

PubMed2001

Social influences on reality-monitoring decisions.

A modified Asch (1951) conformity paradigm was used to study the impact of social influence on reality-monitoring decisions about new items. Subjects studied pictures of some objects and imagined others. In a later test phase, they judged whether items had been perceived in the study phase, had been imagined, or were new. Critically, for some items, the subjects were informed of a confederate's response before rendering a judgment. Although the confederate was always correct when they responded to old items, for new items, the confederate responded perceived, imagined, or new, or did not respond (baseline). In two experiments, we show that memory for new items was influenced by an erroneous response of the confederate. Social conformity was reduced by undermining the credibility of the confederate (Experiments 1A and 1B), and the confederate's influence was evident even after there was only a 20-min delay between study and test (Experiment 2), when the subjects were 87% accurate on new baseline items. These experiments reveal the power of social influence on reality-monitoring accuracy and confidence.

Adult↗