Identifying Hypothesis Confirmation Behaviors in a Simulated Murder Investigation: Implications for Practice

Abstract

Investigators have been shown to be prone to accessing information that confirms their preferred hypothesis. This tendency has been termed hypothesis confirmation. Hypothesis confirmation behaviour was explored in two studies using a computer administered simulation of a murder investigation. In Study 1, hypothesis confirmation behaviour did not differentiate successful and unsuccessful participants. However, unsuccessful participants stored more confirmatory information than non‐confirmatory information. Successful participants did not show this pattern. In Study 2, unsuccessful participants tended to settle early on a suspect and then acquired information that supported their decision. Successful participants tended to consider a number of suspects for longer and accessed a greater diversity of information. Taken together, these findings are highly suggestive of the role of information acquisition as an important component of hypothesis confirmatory behaviour, which is associated with unsuccessful information processing in the context of a simulated murder investigation. Implications for practice are presented. Copyright © 2012 John Wiley & Sons, Ltd.

Reconstructing with trace information: Does rapid identification information lead to better crime reconstructions?

“…If an analysis of this trace results in a database‐match, this person could be wrongfully accused of the crime and remain the main suspect within the investigation. After all, literature shows that once an idea is formed, people have difficulty changing it (Nickerson, ), and several studies have shown that investigators are prone to confirmation bias and belief perseverance and look for confirming evidence of their initial idea (Ask & Granhag, ; Rassin, Eerland, & Kuijpers, ; Wastell, Weeks, Wearing, & Duncan, ). This study showed that CSIs also have the tendency to look for confirmation rather than falsification.…”

Choice and Background Knowledge: How do Individuals Evaluate Accumulating Evidence in A Murder Scenario?

“…The use of fictional case files containing a description of a crime, a police report and a set of evidence implicating one or more suspects is an established method for examining decision making in the context of complex evidence (Ask & Granhag, 2007;O'Brien, 2009;Wastell, Weeks, Wearing, & Duncan, 2012b). This method allows the examination of how various factors may influence the final judgment produced, such as evidence presented, time allowed for decision production, and commitment to a decision option (Ask & Granhag, 2007;O'Brien, 2009;Simon et al, 2004).…”

“…This limitation meant that any individual preference for facts and possibly different stories was not able to be tested. However, Wastell et al (2012b) did facilitate such individual evidence accumulation and found that a majority of participants were more inclined to select information consistent with their initial preference than to suspend judgment for any length of time. Participants in Wastell et al's experiment also exhibited information selection behaviour consistent with argument theory.…”

Where Bias Begins: a Snapshot of Police Officers’ Beliefs About Factors that Influence the Investigative Interview with Suspects

“…stress or time constraints; Evans 2006). When making decisions in high-stress/high-cognitive load situations, individuals are more likely to come to their conclusions quickly and use very little of the information available to them (Keinan 1987;Trippas et al 2013;Wastell et al 2012). Belief-based decisions under pressure occur because the likelihood of evaluating all available information is reduced (Rassin et al 2008).…”