Psychiatric disorders and access to assisted suicide: A comparative analysis of selected international experiences and medico-legal critical issues in the Italian context

Assisted suicide in patients affected by mental disorders represents one of the most controversial issues in contemporary legal medicine, as it requires distinguishing between an autonomous, stable, and competent request for death and an expression of suffering potentially related to the psychiatric disorder itself. The aim of this narrative medico-legal review is to comparatively analyze the international regulation of medically assisted dying in the presence of psychological suffering, with particular attention to the concept of irremediability of mental suffering and to the limits imposed by the Italian legal system. A narrative review of the international medico-legal, bioethical, and legal literature was conducted, integrated with a comparative analysis of the main legislative, jurisprudential, and professional sources relating to assisted suicide and euthanasia in patients with psychiatric disorders. Jurisdictions were selected through purposive, information-oriented sampling to maximize contrast among permissive, autonomy-based, restrictive, and terminal-illness-based regulatory models. The analysis reveals marked international heterogeneity. The Netherlands and Belgium constitute the most developed models of access to medically assisted dying for psychiatric suffering, subject to rigorous procedures for assessing irremediability and decision-making capacity. Switzerland and Germany attribute comparatively greater weight to individual self-determination, although through different normative arrangements. Canada has suspended until 17 March 2027 the eligibility of mental illness as the sole underlying medical condition for medical assistance in dying. Conversely, the United States, Australia, and New Zealand substantially restrict access to patients affected by terminal conditions or diseases severely limiting survival. Despite procedural differences, the main element of divergence among legal systems concerns the definition of irremediable psychological suffering and the methods used to assess decision-making capacity. In the Italian context, Constitutional Court judgments no. 242/2019 and no. 135/2024 confirm that non-punishability of assistance in suicide requires the cumulative satisfaction of strict requirements, including an irreversible disease, suffering considered intolerable, full capacity for self-determination, and dependence on life-sustaining treatments, with verification by the National Health Service and involvement of the territorially competent ethics committee. Subsequent judgment no. 204/2025 further clarified that regional organizational measures cannot modify these substantive prerequisites. Psychiatric illness alone is therefore not currently sufficient to meet the requirements established by the Italian constitutional framework. The comparative analysis suggests that the fundamental medico-legal and ethical issue does not lie exclusively in ascertaining the applicant's autonomy, but rather in the absence of universally shared clinical criteria for defining the irremediability of mental suffering and distinguishing it from residual therapeutic potential. This uncertainty remains the principal limitation to extending medically assisted dying to psychiatric patients.