Epidemiological Aspects of Homicide: Sexual Murder Must Be Understood in Context
Before we can study sexual murder further, an understanding of the epidemiology of homicide is necessary since sexual homicide cannot be studied or understood in isolation. To study only sexual murder is comparable to a physician who only studies one disease. Many of the characteristics of the nonsexual murderer are the same as the sexual murderer, but some traits and behaviors do differ. Thus, sexual homicide is a subtype of homicide, and in order to fully understand sexual murder, it must be viewed in context.
Incidence of Crime and Homicide
A review of the UCR reveals that the majority of all present-day murders are basically of the Cain-Abel type. The patterns of homicide have also been fairly consistent over extended periods of time. For example, from 1837 to 1901, most murders were domestic, followed in frequency by murders committed during the course of another felony (Attick, 1970), a pattern that holds up to the present. However, in order to estimate and understand the prevalence of sexual murder, we first need to place it in proper context—not only its incidence in relation to nonsexual homicide but its incidence in relation to all crime.
Approximately 85% of all reported crime is property crime which includes offenses such as larceny, motor vehicle theft, and burglary. About 12% of all crime is a violent crime such as aggravated assault, robbery, forcible rape, and murder. Among violent crimes, murder is the least frequent offense, accounting for only 1.3% of violent crime.
In 2018, assault accounted for 66.9% of all violent crime, followed by robbery (23.4%) and rape (8.4%). There were 7.2 million property crimes (17.6% clearance rate) and
1.2 million violent crimes (45.5% clearance rate). And while the statistics for crimes such as motor vehicle theft, burglary, and larceny may be inaccurate (due to a variety of reporting problems), the statistics regarding homicide may also be somewhat misleading, even given the unambiguous nature of the act. For example, because of recent advances in emergency medicine, or due to particular circumstances or interventions, some intended murders wind up as assaults, whereas some intended assaults may end up as murder (Doerner and Speir, 1986).
Although murder occurs least frequently in comparison to other offenses, the clearance (arrest) rate for murder is higher than the rates for all other crimes. Murder is generally not a difficult crime to solve (Geberth, 1996), since most homicides involve family members, friends, and acquaintances, similar to Cain and Abel. However, sexual homicide may be an exception, since many sexual murders are not of the Cain-Abel variety; sexual murderers sometimes kill strangers, making apprehension much more difficult. Even with the absence of hard data, most experts (Meloy, 2000; Swigert, Farrell, and Yoels, 1976) believe that sexual homicide is extremely rare. Of those who murder once, only a small fraction murder again—for example, in the form of serial sexual homicide (Busch and Cavanaugh, 1986). Thus, when one examines the crime statistics as a whole, it is clear that sexual murder is an extremely rare occurrence.