From the NYTimes:
In addition to a growing sensitivity to the rights of animals, another significant reason for the increased attention to animal cruelty is a mounting body of evidence about the link between such acts and serious crimes of more narrowly human concern, including illegal firearms possession, drug trafficking, gambling, spousal and child abuse, rape and homicide. In the world of law enforcement — and in the larger world that our laws were designed to shape — animal-cruelty issues were long considered a peripheral concern and the province of local A.S.P.C.A. and Humane Society organizations; offenses as removed and distinct from the work of enforcing the human penal code as we humans have deemed ourselves to be from animals. But that illusory distinction is rapidly fading.
The article goes on to make this claim:
“A Study of Firesetting and Animal Cruelty in Children: Family Influences and Adolescent Outcomes,” found that over a 10-year period, 6-to-12-year-old children who were described as being cruel to animals were more than twice as likely as other children in the study to be reported to juvenile authorities for a violent offense. In an October 2005 paper published in Journal of Community Health, a team of researchers conducting a study over seven years in 11 metropolitan areas determined that pet abuse was one of five factors that predicted who would begin other abusive behaviors. In a 1995 study, nearly a third of pet-owning victims of domestic abuse, meanwhile, reported that one or more of their children had killed or harmed a pet.
