Police officers' use of evidence to elicit admissions in a fictitious criminal case

Abstract

We examined how police officers planned to interview suspects in a situation where they lacked information about a critical phase of a crime (i.e., the time during which the crime took place) but possessed information about less critical phases of the crime (i.e., the time before and/or after the crime took place). The main focus was the officers' planned use of the available information (evidence) to elicit admissions about the critical phase. A survey was distributed to police officers (n = 69) containing a fictitious murder case for which they were to prepare an interview with a suspect. The investigators planned to disclose the evidence more often in a strategic manner (obtaining the suspect's statement and exhausting alternative scenarios before revealing the evidence) than in a nonstrategic manner (revealing the evidence before requiring an explanation). The investigators' most frequently reported reason for their planned evidence use was to collect additional information about the particular phase to which the disclosed evidence pertained. It was rare that the investigators planned to disclose the evidence about a less critical phase of the crime in order to elicit admissions about the more critical phase (e.g., by disclosing the evidence to try to shift the suspect's counter-interrogation strategy from less to more forthcoming). The investigators may benefit from recent research showing that strategic evidence disclosure can be used as a means to elicit admissions about a phase of a crime for which information is lacking.

Police Officers’ Perceptions of Statement Inconsistency

“…The questions were kept broad to understand how officers use inconsistency types in general. Moreover, the findings concur with previous studies investigating police officers' perceptions of statement inconsistency in other countries (Alison, 2005;Greuel, 1992;Tekin et al, 2017) as well as with experimental studies examining statement inconsistency (Granhag, Rangmar, & Strömwall, 2015;Mac Giolla & Granhag, 2015), which support the validity of police officers' reports in this study.…”

“…Officers were asked whether they thought that liars who are presented with incriminating evidence, after explanations for it have been exhausted, would be more likely to change their statement to fit it with the evidence or to maintain their statement, risking statement-evidence inconsistency. Previous research has found that police officers in several countries tend to employ the SUE technique in investigative interviews (Tekin, Granhag, Strömwall, & Vrij, 2017). The application of this technique is more likely to elicit statement-evidence inconsistency than within-statement inconsistency in liars’ statements (Granhag et al, 2013; Tekin, Granhag, Strömwall, & Vrij, 2016).…”

Collective interviewing: The use of a model statement to differentiate between pairs of truth‐tellers and pairs of liars

“…However, the findings of the current study are only generalizable to situations whereby pairs of suspects claim to have been together at the time the crime took place. The model statement should be used alongside other strategies found to gather information and increase cues to deceit (e.g., the Strategic Use of Evidence; Tekin et al ., ; Tekin, Granhag, Strömwall, & Vrij, ). After all, the more strategies we have in place to increase information gathering and elicit cues to deceit, the more likely we are to accurately differentiate between truthful and lying suspects.…”