Non-optimal decision making from arrest to the court trial: exploring the role of criminal thinking, hostile perceptual biases, anger and minority ethnic heritage

Background Individuals in the criminal justice system face high-stakes decisions that can lead to life-altering outcomes - including imprisonment and, in some cases, wrongful conviction. Making optimal choices is essential for achieving the best outcomes. In this process non-vulnerable individuals, in line with Rational Choice Theory assumptions, are presumed capable of rational decision-making. Yet psychological research, based on Prospect Theory, shows individuals make biased intuitive decisions. In forensic contexts, professionals and defendants alike are susceptible to cognitive biases. The criminal thinking styles perspective explains how maladaptive thinking and cognitive biases contribute to poor decisions leading to recidivism. This thesis explores how such thinking may also explain non-optimal decision-making across initial stages of the criminal justice journey.

Aims This thesis, using a multi-study approach, explored how criminal thinking may help explain three facets of decision-making within the criminal justice process: development of hostility biases; adoption of less-rational decision-making styles and poor performance on decision tasks; and non-optimal decisions made in the journey from arrest to trial. 

Methods A critical realist stance within a post-positivist framework was adopted, employing multiple quantitative methods across four studies. These included self-report measures of criminal thinking, decision-making styles, competence, outcomes, and hostility biases, alongside an experimental task on emotion perception and a decision-making measure covering the arrest-to-trial process. 

Results Findings from multiple regression analyses, in Study One (N=476), suggested criminal thinking predicts hostility biases; in Study Two (N=266), indicated an association between limited rational decision-making in normative tasks and elevated criminal thinking. In Study Three (N=292), binomial logistic regression analysis showed elevated criminal thinking explains non-optimal decisions in simulated criminal justice procedures.  Similarly, Study Four (N=192) found a forensic sample reported more non-optimal decisions from arrest to interview when criminal thinking was elevated. 

Conclusions This thesis fills a gap in knowledge, the role of criminal thinking on non-optimal decisions of suspects in the journey from arrest to court trial. Overall, it concluded that individuals with elevated criminal thinking may face negative outcomes due to increased risk of non-optimal decision-making. To promote fairness, criminal justice system policymakers should implement targeted interventions and training to ensure these individuals can fully benefit from legal provisions in the criminal justice process.