Intimate Partner Homicides in Norway 1990-2020: An Analysis of Incidence and Characteristics.

Intimate partner homicide (IPH) is an extreme outcome of intimate partner violence (IPV). It is a societal challenge that needs to be investigated over time to see whether changes occur concerning the incidence of IPH, IPH characteristics, socioeconomic factors, and contact with service providers. This study includes the total Norwegian cohort of IPHs between 1990 and 2019 with a final conviction (N = 224). Poisson regression was applied to model the incidence rate of homicide and IPH between 1990 and 2020 as well as the incidence rates of immigrant perpetrators and victims. Multivariate logistic regression analyses were used to test the association between characteristics and period 1990-2012 compared to after 2012 as dependent variable. The results show that though homicide incidence rates in Norway declined steadily and significantly after 1990, IPH rates did not begin to decline until 2015. The following IPH characteristics showed reduced incidence after 2012: IPH-suicide, perpetrators with a criminal record, and IPHs perpetrated subsequent to preventive interventions towards the perpetrator. Sentence length in IPH cases had increased. Changes were not observed for any of the other IPH characteristics investigated. IPH is often the culmination of long-term violence and can be prevented, even if risk assessment is challenging due to the low base rates.