Solvability factors of homicide in Australia : an exploratory analysis

Abstract

Over the last few years the nexus between criminological research and law-enforcement practice has been strengthened through the increased cooperation of police and researchers working towards common goals. The Australian Institute of Criminology, through its National Homicide Monitoring Program, continues to provide police, policy-makers and the public with timely research on homicide and its subsets. The present paper follows this tradition by outlining the latest research on homicide, but it also introduces another element to research: the view of the practitioner. This study examines the factors that differentiate solved and unsolved homicides in Australia, and includes the perspectives of homicide investigators in determining which factors are important in solving a given homicide. In brief, the study found that unsolved homicides were more likely than solved homicides to occur in the course of other crime and at a location other than a residential premise. The victims of unsolved homicides were more likely to be killed with a firearm, and were likely to be aged 30 years or older. Adam Graycar Director One of the issues that is often overlooked when discussing homicide is the efficacy of the police in identifying and charging an offender. Advances in technology such as DNA typing (Weedn & Hicks 1998), and innovations such as Cold Case Squads (Poole & Jurovics 1993; Regini 1997) are helping reduce the number of homicides which remain unsolved. However, there is little valid research about what makes a particular homicide more or less likely to be solved, and most of what is believed has not been verified in any way. While the insight of experienced homicide investigators will always be important for providing direction to a homicide investigation, research can also play an important role in informing practice. Review of the Literature There is considerable concern, primarily in the public arena, about serious violent crimes such as homicide, but little attention is paid to the ability of police to solve these crimes. Evidence from the National Homicide Monitoring Program suggests that the percentage of homicides that remain unsolved in Australia has remained relatively stable at about 12 per cent over the years. However in the United States, various authors agree that in the last two decades the homicide clearance rate has decreased substantially (Riedel & Rinehart 1996; Wellford & Cronin 1999, 2000).1 Gilbert (1983) reports that investigators are generally of the opinion that the increase in stranger homicides in the United States, crimes which are generally considered more difficult to solve, is at least partly responsible for the decreasing clearance rate. Wellford and Cronin (2000) add that decreases in police resources and the decrease in the likelihood of bystanders and witnesses to provide information, particularly in urban areas, also contributes to the increase in unsolved homicides. Some years ago, Keppel and Weis (1994) observed that there was no empirical research on solvability factors relevant to homicide investigations. Since that time, little has changed (Wellford & Cronin 2000). Keppel and Weis point out that while homicide itself has been the subject of much research, the process of investigating homicide has not. Much of what is treated as canon by investigators is generally anecdotal information passed down by word-of-mouth. Furthermore, textbooks devoted to the subject primarily rely on the subjective experience of the author. The dearth of substantiated knowledge is not surprising, as police investigation is an area in which criminologists and other academics have traditionally shown little interest. However, with police organisations becoming increasingly open to assistance from outside experts, this is an area which could benefit from attention. One approach that various researchers have taken to investigate this issue is to do statistical analyses of incident variables to see how solved and unsolved crimes differ. …