A comparable truth baseline improves truth/lie discrimination

In a comparable truth baseline (CTB), a knowingly truthful baseline statement is compared to a statement of interest, and deviations in verbal details possibly indicate deceit. In two experiments, we investigated whether a CTB can improve truth/lie discrimination when verbal details are coded by independent raters (Experiment 1) and when judged by naive observers (Experiment 2). In addition, we investigated whether lie tellers would calibrate their lies to match the detailedness of their baseline. Results showed no evidence of calibration. As expected, truths were more detailed than their corresponding baselines, while lies were less detailed. Significant differences emerged for spatial, visual and action details. Experiment 2 did not show that a CTB improved observers' lie detection accuracy. Taken together, our results showed that a deviation in details from a CTB may serve as a helpful aid in lie detection.