Justice without bias: A systematic review and meta-analysis of interventions aimed at reducing jury bias in Rape and sexual assault trials

Abstract

Jury bias in Rape and Serious Sexual Offence (RASSO) trials remains a serious concern, shaping perceptions of victims and defendants and influencing verdicts and sentencing. Jurors often rely on cognitive and social biases (e.g., rape myths, credibility bias, and racial prejudice) leading to wrongful acquittals or convictions. These biases also drive sentencing disparities, where extralegal factors like race, gender, or victim behavior affect punishment severity, undermining legal consistency and public trust. Although research has explored interventions to reduce bias, mixed results have limited their adoption in courtroom practice. This systematic review and meta-analysis synthesized findings from 44 studies assessing the effectiveness of interventions aimed at reducing juror bias (29 victim-focused, 12 defendant-focused, 3 both). For victim-related biases, expert testimony and juror education were most effective, while judicial instruction was less effective (though all showed small effect sizes). For defendant-related biases, only expert testimony was effective. Victim-focused interventions reduced credibility and rape myth biases, whereas defendant-focused interventions reduced rape myth, racial, and media biases. Future research should refine methodologies, improve ecological validity, and examine long-term impacts in courtroom settings. Additionally, strategies addressing other biases (e.g., gender identity, neurodiversity) require development. This review supports evidence-based interventions to mitigate bias and promote impartiality in RASSO trials.