The factors associated with forensic psychiatrists' decisions in criminal responsibility and social dangerousness evaluations

Despite the central role in criminal trials, there is little research on the decision-making processes of experts in forensic psychiatry. We aimed to investigate the role of sociodemographic, psychopathological, and criminological characteristics in forensic psychiatric decisions on criminal responsibility and social dangerousness in criminal trials. We analyzed 302 forensic psychiatric reports provided by 16 forensic psychiatrists from the North, Central and Southern Italy. Defendants' psychiatric symptom severity was evaluated through the 24-item Brief Psychiatric Rating Scale (BPRS), the Clinical Global Impression (CGI) scale and the Global Assessment of Functioning (GAF). Defendants judged not criminally responsible (Not-CRDs) presented with more severe psychiatric symptoms (positive symptoms, negative symptoms, manic excitement / disorganization), were more likely to be female, to be affected by a schizophrenia spectrum disorder, or bipolar spectrum disorder and to have had a higher number of previous psychiatric treatments and previous involuntary hospitalizations compared to their criminally responsible counterparts. Not-CRDs affected by a schizophrenia spectrum disorder, personality disorder, with severe psychiatric symptoms and with histories of criminal convictions and more victims were more likely to have received a judgment of social dangerousness. The forensic psychiatric evaluations were carried out on average of 770 days after the time of the crime, which in light of the other results, suggests an effect of the perceptions of the expert on the judgment of responsibility, raising the possibility of time bias on forensic judgments concerning defendants' mental responsibility. •Higher manic excitement, positive and negative symptoms at time of forensic evaluation differentiate Not-CRDs from CRDs.•Not-CRDs are more likely to be female, to suffer from schizophrenia spectrum disorders, and bipolar spectrum disorders.•Social dangerousness is more likely to be associated with schizophrenia spectrum disorders and personality disorders.•The wide temporal distance between the forensic psychiatric evaluation and the crime suggests the possibility of time bias.