Intimate partner homicide rates and characteristics

Aims: The overarching objective of present dissertation project is to study trends and characteristics of intimate partner homicide (IPH), and to investigate whether the trends and characteristics differ depending on homicide type or gender. Study I aims to compare rates of IPH and nonintimate partner homicide (non-IPH), and to examine gender-specific trends of IPH rates and characteristics. Study II aims to identify socio-demographic and criminological characteristics in perpetrators and victims of IPH, and to examine whether they differ from non-IPH. Study III aims to identify to what extent IPH and non-IPH perpetrators suffered from mental illness and mental disorder, prior or in connection to the offense, and to investigate history of mental illness and mental disorder in victims of IPH and non-IPH. Study IV aims to identify similarities and differences between male and female perpetration of IPH.

Methods and Materials: Study I is based on the European Homicide Monitor, retrieved from the National Council for Crime Prevention, which holds information from police files, court verdicts and forensic psychiatric reports. The population-based study includes all solved homicides (N = 1,725) in Sweden between 1990 and 2013. The studies II-IV are based on data from the Forensic Homicide Database, which is a dataset created by the research group. The population-based dataset holds information from forensic autopsies, forensic psychiatric evaluations, forensic toxicological tests, the National Crime Register, the National Patient Register, preliminary police investigations, and court files. Study II and III are based on data on all maleperpetrated homicides (N = 211) in Sweden between 2007 and 2009, while study IV is based on all female-perpetrated (n = 9) and stratified male-perpetrated (n = 36) IPHs within the same time frame.

Results and Conclusions: Study I illustrates distinct trends in rates across homicide types (IPH vs. non-IPH) and gender (female versus male perpetrated IPH). The study also elucidates a shift in characteristics over time in male-perpetrated IPHs. Study II demonstrates that IPH perpetrators are more conventional with regards to socio-demographics and criminal history. On the other hand, homicide-suicides are predominant in IPH perpetrators. Study III reveals that, irrespective of homicide type, only a minority of perpetrators suffer from mental illness. However, approximately one third of the perpetrators had been diagnosed with a mental disorder at some point in life. Study IV indicates that female IPH perpetrators differ from their male counterparts in terms of being more psychosocially aggravated and more likely to have been victimized by the male victim.

List of scientific papers

I. Caman, S., Kristiansson, M., Granath, S., & Sturup, J. (2017). Trends in rates and characteristics of intimate partner homicides between 1990 and 2013. Journal of Criminal Justice. 49, 14-21.
https://doi.org/10.1016/j.jcrimjus.2017.01.002

II. Caman, S., Howner, K., Kristiansson, M., & Sturup, J. (2017). Differentiating intimate partner homicide from other homicide: A Swedish population-based study of perpetrator, victim and incident characteristics. Psychology of Violence. 7(2), 306-315.
https://doi.org/10.1037/vio0000059

III. Caman, S., Kristiansson, M., Sturup, J., & Howner, K. Psychiatric characteristics and intimate partner homicide: Mental illness and mental disorders in perpetrators and victims. [Manuscript]

IV. Caman, S., Howner, K., Kristiansson, M., & Sturup, J. (2016). Differentiating male and female intimate partner homicide perpetrators: A study of social, criminological and clinical factors. International Journal of Forensic Mental Health. 15(1), 26-34.
https://doi.org/10.1080/14999013.2015.1134723