Assessing not guilty by reason of insanity: A case file study of expert reports in a single judicial district

Although expert assessments play a crucial role in insanity decisions, there is a lack of systematic knowledge in Belgium regarding their implementation, rationale, and variation of these assessments. This study aims to partially fill this gap by analyzing the assessment process for criminal responsibility in Belgium through a literature review and empirical research. In summary, the literature shows that Belgian expert reports exhibit significant variation in terms of diagnostics, use of sources, risk assessment, and justification of criminal irresponsibility. An analysis of case files from 2012–2013 in one judicial district confirms that the quality of expert reports leaves room for improvement. Justifications for diagnoses and criminal responsibility are often lacking, and risk assessments are frequently unstructured. Furthermore, both lawyers and judges tend to adopt a largely uncritical stance, leading to poorly substantiated judgments. To improve the quality of reports, the authors advocate for additional guidelines, a legal standard for lack of criminal irresponsibility, additional training for judges, and more debate during court proceedings.