Aldert Vrij

We tested the efficacy of cognitive credibility assessment (CCA) to discriminate between truth tellers and lie tellers in three types of lie scenarios: omission lies, embedded lies and total fabrications. We expected CCA to be most effective when lie tellers must make up most details: in the fabrication lie condition. Sixty participants were interviewed about two memorable events. They told the truth about one event and lied (omission lie, embedded lie or total fabrication) about the other event. The order of being truthful and deceptive was counterbalanced. Six verbal cues were examined: total details, complications, common knowledge details, self‐handicapping strategies, plausibility and predictability. A multivariate significant Veracity main effect occurred. Participants reported more complications, and their statements sounded more plausible and less predictable when truth‐telling compared to lying. Significant Veracity × Type of Lie interaction effects did not occur, neither at a multivariate nor at a univariate level.

Investigative interviewing research focuses on developing interviewing strategies, tools and methods aimed at collecting information and evidence from human sources, such as witnesses and suspects....

Interrogators use diverse techniques, and suspects try to analyze these to infer the amount of police evidence (perception of evidence). However, the link between technique types and the perception remains understudied. We examined perceptions of 27 evidential (e.g., disclosing evidence) and non‐evidential (e.g., rapport‐building) techniques in Study 1 ( N = 59 prisoners/detainees) and Study 2 ( N = 117 laypersons). We predicted evidential techniques would elicit higher perceived police evidence than non‐evidential ones. This hypothesis was partially supported in both studies: evidential techniques involving substantiated claims consistently yielded higher perceived evidence than non‐evidential techniques; however, unsubstantiated evidential techniques did not consistently differ from non‐evidential ones in perceived evidentiary value. Exploratory comparisons further revealed that detainees and prisoners perceived non‐evidential/crime‐irrelevant techniques as indicative of significantly less police evidence than laypersons, with broader perceptual variability observed across numerous individual techniques.

In standard investigative interviews, follow-up questioning from a free recall is typically based on the core topics of the free recall that are relevant to the event under investigation. We suggest the Segmented Interview as an alternative in which each free recall topic is partitioned into segments, and focused questioning occurs for each topic and segment separately, regardless of their relevance to the event under investigation. We expected the focused questioning of the Segmented Interview to elicit more details and Veracity cues than a Structured Interview. All participants (N = 80) completed three activities, of which only the second was different: Truth tellers visited a store, whereas lie tellers stole an envelope with money. Participants were then interviewed and provided a free recall, followed by open questions based on the Segmented or Structured Interview protocol. The Segmented Interview elicited more information and Veracity cues than the Structured Interview. These results suggest that the Segmented Interview may be a promising interview technique for eliciting information and detecting lies.

Background: People sometimes lie by deliberately leaving out information. Such omission lies can have different sizes: Lie tellers can deliberately omit less or more information. We examined the effect of omission size on verbal cues to deceit. Method: A total of 152 participants followed a target person during his mission in which he met two other persons. In the debrief interview, truth tellers reported all they could remember; small-omission lie tellers omitted one meeting and large-omission lie tellers omitted both meetings. The analyses focused on the parts of the mission all participants reported truthfully. We distinguished between essential information (parts of the mission surrounding the omission) and non-essential information (parts of the mission that were not close to the omission). We examined external, contextual, internal details, complications, common knowledge details, and self-handicapping strategies. We also measured participants’ strategies. Results: Truth tellers reported more complications than both groups of lie tellers in both the essential and non-essential information parts. Lie tellers were more than truth tellers inclined to keep their story simple. Conclusion: It further supports the notion that omission lie tellers are inclined to keep their stories simple and that, perhaps because of that, complications emerged as a veracity indicator. Antecedentes:, A veces las personas mienten deliberadamente omitiendo información. Las mentiras por omisión pueden tener tamaños diferentes: los mentirosos pueden omitir más o menos información a propósito. Analizamos el efecto del tamaño de la omisión en los indicios verbales asociados al engaño. ,Método:, Un total de 152 participantes siguieron a un hombre durante una misión, en la que éste se encontró con otras dos personas. En la subsiguiente entrevista, a los que decían la verdad se les pidió que narraran todo lo que podían recordar y a los que mentían con una ligera omisión que omitieran un encuentro y a los que mentían con una gran omisión que omitieran ambos encuentros. Los análisis se centraron en las partes de misión que todos los participantes contaron con sinceridad. Se distingue entre información esencial (omisión de información adyacente a la misión) e información no esencial (omisión de información no adyacente a la misión). Se analizan los detalles externos, contextuales e internos, las complicaciones, detalles de conocimiento común y las estrategias de auto-justificación. También se midieron las estrategias de los participantes. ,Resultados:, Los que decían la verdad informaron de más complicaciones que ambos grupos de mentirosos, tanto en las partes esenciales como en las no esenciales de la información. Los mentirosos tendían más que los sinceros a simplificar su relato. ,Conclusión:, Se refuerza la idea de que los mentirosos tienden a simplificar su relato y que, tal vez por ese motivo, las complicaciones aparecían como indicadores de veracidad.