Homicide Injury Quantification: Measures of injury severity in homicide victims and associations with homicide characteristics

  • Date:
  • Location: Fåhraeussalen, Rudbecklaboratoriet, Dag Hammarskjölds väg 20, Uppsala
  • Doctoral student: Tamsen, Fredrik
  • About the dissertation
  • Organiser: Rättsmedicin
  • Contact person: Tamsen, Fredrik
  • Disputation

Some previous studies have found that the amount and severity of injuries in homicide victims correlate with different homicide characteristics, such as the victim-offender relationship and drug influence of the offender. If such relationships exist, they may be used by homicide investigators as part of an offender profiling.

Furthermore, injury severity may be helpful in understanding the nature of lethal violence. If the injuries change over time or differ between regions, this may say something about the underlying causes and thus help society to take preventive measures. However, measures of injury severity are often missing in homicide epidemiology. This may in part be due to a lack of standardized and accessible ways to quantify injuries in homicide victim.

To address these issues, there is a need for methods to quantify injury severity in homicide victims. The aim of the current thesis was to investigate different types of injury measures and their applicability to homicide victims. The aim was also to use such measures to address research questions related to offender profiling.

Starting off with injury scores used in trauma research and two scores developed specifically for homicide victims, these measures were applied to a general homicide population. Since there is no obvious “gold standard” for injury severity quantification on homicide victims, one had to be defined to validate the applied methods. Out of forensic experience and rational reasoning, the Sum of all AIS scores (SAIS) was proposed as a reference measure. The other scores were then evaluated through their correlations with the SAIS.

In the following study, the injury severity in homicides from different time periods was measured. There were statistically significant increases over time with respect to excessive injuries and the number of lethal injuries per victim. These changes can reflect both a brutalization of homicidal violence, improved trauma care, or shifts in the methods by which people are killed.

Next, the associations between injury severity and homicide characteristics were analysed. No relevant associations between injury severity and victim-offender relationship were found. Neither were there any connections between benzodiazepine influence in the offender and injury severity on the victim. Thus, the studies do not support the use of injury severity scores for offender profiling in a general homicide population.