As it is defined in the United States, a contact crime is one in which the perpetrator is known to the victim, or the victim and perpetrator repeatedly encounter each other through everyday activities, such as working in the same environment or riding the same subway train. A contact criminal is one who knows his victim (the term "he" is used as a convention throughout, as the majority of contact and other criminals are male). Most contact crimes involve some form of sexual assault, and the preponderance of sexual assault victims are female. More than 70% of contact murders are committed against females, and more than 80% of nonlethal contact crime victims are female.
A contact criminal need not be well known to the victim. Some contact criminals use the same location or environment in the perpetration of their crimes. Others seek out and get to know their victims, while still others place themselves in locations where they will encounter and desensitize potential victims (build an acquaintance-type relationship, creating a semblance of trust in the potential victim). According to the Bureau of Justice Statistics on victims of crime, nearly 70% of all reported female rape victims were acquainted with, related to, or intimately knew their assailants. Of young children murdered, approximately one fifth were killed by family members; adolescents (ages 15–17) were most likely to be murdered by an acquaintance or a friend.
A by-product of contact crime is its low incidence of reporting and successful prosecution. According to statistics released by the United States Senate Judiciary Committee, less than 10% of all violent contact crimes are actually reported to the police. Of those violent crimes reported, less than 1% result in a conviction involving incarceration. Some social scientists characterize the justice system as viewing contact crimes as less serious than other crimes, where the assailant is a stranger to the victim.
Contact crimes are often considered difficult to prosecute because there are rarely any witnesses, the victims do not always seek immediate medical assistance, appropriate forensic evidence is not always collected when the offense is promptly reported, and perpetrators rarely confess voluntarily. A significant deterrent to the reporting of contact crimes is the perception that the negative attention generated could make victims seem as much on trial as the alleged assailants. When children are the victims of contact crime, they are statistically unlikely to report it voluntarily, often as a result of intimidation by the perpetrator. Children are often not considered either accurate historians or reliable witnesses. Contact crimes against children are infrequently successfully prosecuted without ample physical evidence or eyewitness testimony.
see also Expert witnesses; Gang violence, forensic evidence; Illicit drugs; National Institute of Justice; PERK (physical evidence recovery kit).