Letter to the Editor regarding the article "Double suicide in Japan in the post-war reconstruction period, with reference to contemporary Japan".

We read with great interest the paper published by Satoh et al. on double suicides in Japan in the postwar period, comparing their findings with those of contemporary Japan. The authors addressed a phenomenon of great forensic interest by placing it in the context of a geographic reality in which the number of suicide pacts has been high since ancient times. We have also been dealing with this topic for some years. We agree that, although suicide pacts were more common in Asia than in the West, this difference is much less evident today. These cases also exist in Italy. In our recent retrospective analysis at the Institute of Forensic Medicine in Milan (one of the main cities in northern Italy), six suicide pacts were recorded between 1993 and 2020. Our case history, although numerically smaller, is consistent with the suicide couples described by Satoh et al. Specifically, we recorded a young couple of lovers, two couples of older spouses, and two couples of friends. In addition, we also had a pair of identical twins. There were also similarities in the causes of death: acute carbon monoxide poisoning, drug ingestion, and inhalation of gas combined with plastic bag suffocation (these latter can be considered complex suicides). However, in two suicide pairs, the cause of death was gunshot injury. In light of these findings, it is very important to compare case histories from different geographic areas, as this may reveal differences related to different sociocultural settings and, at the same time, unexpected similarities. However, we would like to highlight an aspect that we believe plays an indispensable role in the proper framing of suicide pacts. Indeed, this terminology refers to all situations in which two people decide to end their lives by mutual consent. Thus, double suicides certainly fall under this definition, but so do cases of homicide–suicide with the explicit consent of the homicide victim. Therefore, the terms “double suicide” and “pact suicide” should not be understood as synonyms, but the former as a subcategory of the latter. Obviously, cases of murder–suicide without the victim’s consent are excluded. As a result, suicide pacts pose a real challenge from a medico-legal perspective, with significant interpretative problems. In this field, multidisciplinary skills are therefore required. The on-site inspection can provide essential information: the mutual position of the victims’ bodies, the condition of the clothing, the location of bloodstains, and the order and cleanliness of the room. Special attention should also be paid to the finding of a weapon near the bodies, which does not always necessarily indicate a suicide. Finally, information should be obtained about the personal background of the victims by interviewing family members and friends. Often they know about family problems, financial difficulties, or health problems that may have triggered the suicide pact. The victim’s medical history is also crucial, as it may indicate a history of psychiatric disorders. Typically, the reasons for suicide pacts reflect the specific historical circumstances in which they occur, such as the impact and psychological distress of the recent pandemic COVID-19. The way people make a suicide pact is also changing as society advances technologically, and suicide pacts have even been documented between strangers negotiated over the Internet, referred to as “net suicides,” or on the microblogging website Twitter. Another important aspect is the presence of farewell letters, as they may indicate the motive for such events and reveal the victims’ common intentions for their joint death. Consequently, the