The Impact of Model Statements on Verbal Differences between Truth and Lies when using a Comparable Truthful Baseline

Baselining is a deception detection technique that compares a statement of interest to a baseline. This study focused on verbal baselining: it examined differences in detailedness between the baseline and the statement of interest as a cue to deception. Across two experiments, participants watched two crime videos and provided two statements: one truthful baseline and one statement of interest, which was either truthful or deceptive depending on the condition. Half of the participants were shown a model statement before giving their responses. In Experiment 1 (using written statements), both the model statement and the baseline independently improved truth/lie discrimination. In Experiment 2 (using spoken statements), however, these effects were not replicated. Importantly, combining a model statement with baselining did not further improve truth/lie discrimination in either experiment. These findings underscore the complexity of verbal lie detection and highlight the need to better understand when and how baselining techniques are most effective.