The Dependence of Reported Homicide Rates on Reported Non-Motor Vehicle Accident Death Rates in US Young Children and Infants, 1940-2007

Abstract

An analysis of the relationship between reported homicides and reported non-motor vehicle accident deaths in young children and infants was performed. Reported young child (aged 1 to less than 5 years) and infant (aged less than 1 year) homicide and non-motor vehicle accident mortality rates in boys and girls in the United States from 1940 to 2007 were analyzed using the 4-parameter logistic model. Homicide rate growth over time displayed sigmoid curves with inflection points near 1968 in young children and near 1984 in infants. Using the maximum and minimum homicide rate asymptotes from those analyses over time, 4-parameter logistic model between homicide rates and non-motor vehicle mortality rates suggests that 84.2% and 94.2% of the variation in young child homicide rates, in boys and girls respectively, can be explained by variation in the corresponding non-motor vehicle accident mortality rates and that 69.4% and 66.3% of the variation in infant homicide rates, in boys and girls respectively, was explained by variation in the corresponding non-motor vehicle accident mortality rates. These findings are consistent with the thesis that changing propensities in the classification of young child and infant deaths as either homicides or non-motor vehicle accident deaths, rather than actual changes in societal violence, may explain a substantial proportion of the reported increases in homicide rates in young children and infants. Moreover, the observation that increases in homicide rates in young children and infants were separated in time by nearly 16 years further supports this thesis.