Mass murder and consecutive suicide in Switzerland: A comparative analysis.

Abstract

Mass murder, the killing of three people in a timely and locally narrowly defined space, is a rare event with extensive consequences on society. In many cases, mass murders end with the offender's suicide. We identified 49 cases of mass murder in Switzerland that had occurred between the years 1972 and 2015. We were granted access to official files of 33 cases. The aim of our study was to identify distinct risk factors for mass murderers who had committed suicide after the crime (MMS) and those who had not (MM) by analyzing differences in sociodemographic, psychological, and criminological features. We identified 16 MMS and 17 MM. The majority of MMS was familicides. Their motive was mainly a perverted sense of loyalty, as opposed to that of MM revenge. The aggression of MMS would mostly be instrumental, the one of MM also reactive. Threats were highly prevalent in both groups, with a higher rate of specific threats in MMS and more generalized threats in MM. They did not differ in the prevalence of mental disorders or rate of prior suicidal ideation. Both type of offenders mainly used firearms. Military weapons were of no importance, contrary to their role with suicide in Switzerland. Mass murder in Switzerland is an extremely rare event that makes the drawing of general conclusions somewhat difficult and the establishing of new laws futile. Our conclusion that the aggression of MMS is premeditated, however, could be helpful with the assessment of future putative offenders. Public Significance StatementMass murder is a rare act that, by its extreme violence, stokes the emotions of the public and hence implies an extraordinary challenge for risk assessment professionals. Mass murder is closely linked to suicide. In this article, we report about the particularities of mass murder with consecutive suicide in Switzerland, a country with a generally low incidence of violent criminality. Mass murders with consecutive suicides in Switzerland are premeditated acts executed by rather well-off middle-aged men suffering from a long-lasting strain and/or personality disorder who never sought professional help and who mainly killed their family and then themselves.

Is familicide a distinct subtype of mass murder? Evidence from a Swiss national cohort

“…In an earlier study of a complete national cohort of mass killers in Switzerland (Ilic & Frei, 2019), we found a high prevalence of mass murders within the family compared with other reporting countries. In this study, therefore, our aim was to extend understanding of familicides by comparing their characteristics with those of other mass murderers in the country over the same period.…”

“…We defined familicide as any act of killing three of more people within one family, bringing the definition in line with that of “mass murder” (Ilic & Frei, ), thus including the killing of spouse and children, but not excluding the killing of children by the mother or the killing of parents and siblings by the children as has been suggested by Fridel (). We did exclude killing of a spouse alone, a single child, and, indeed, any single person killings.…”

A classification of combined homicide‐suicide: An update—Part I: Introduction and psychopathology

“…On a number of parameters, the authors did not find much difference between the two groups, even in the presence of mental disorders and rate of previous suicidal ideation. However, the majority of those who also committed suicides targeted family members and showed more advanced planning for the act [29].…”

A classification of combined homicide–suicide: An update—Part II: Intrafamilial homicide–suicide

“…Ilic and Frei [43] define familicide broadly as “killing three or more people within one family” (p. 3). Where defined as three or more homicide victims, intrafamilial is the most common type of mass killing [43].…”