Experimental Evidence of Bias in Assessments of Familial Homicide Cases

Abstract

Biases that have been detected in crime investigation and sentencing threaten the commonly accepted goal of objective and fair treatment of cases in legal processes. In this vignette study, we examined how the offender gender (male or female), the crime type (familicide [killing of partner and one or more children] or filicide [killing of one or more children]), and the relatedness between the offender and the (biological or step) child victim(s) affected university students’ assessments of familial homicide cases (e.g., regarding adequate punishment and the main cause of the crime). The vignette study was conducted as an online survey with 164 participants recruited from the University of Turku, Finland. Consistent with our central hypothesis, female offenders were associated with mental illness to a larger degree than male offenders. Similarly, offenders killing biological children were associated with mental illness to a larger degree than offenders killing stepchildren. The findings of the current study mainly support previous literature on biases in assessments of familial homicide cases. Becoming aware of the biases, people can critically consider their assessments, which enables less biased treatment of criminal cases.