The language of high-stakes truths and lies: Linguistic analysis of true and deceptive statements made during sexual homicide interrogations

Purpose

Few studies have assessed deception during real-life, high-stakes encounters. This study is one of the largest and most geographically diverse to investigate how criminal suspects lie during investigative interviews. It is also one of the most specific; focusing solely on those who committed sexually motivated homicides.

Methods

Sections of transcripts from 52 sexually motivated homicide offender interrogations were analysed using Linguistic Inquiry and Word Count software. Truthful (n = 27) and deceptive (n = 25) statements, corroborated through physical evidence, were then compared using the reality monitoring (RM) model of deception.

Results

Support for the RM model was mixed. Truthful statements contained more motion and spatial details. There were no significant differences between true and deceptive statements when comparing perceptual, affective, and cognitive process details.

Conclusions

The results support the notion that there are verbal cues to deception detectable in high-stakes, real-life situations. It also provides a starting point to assess these cues in special forensic populations.