According to
Outpost for Hope, people can become unreported missing for a variety of reasons, including: • the person may be
estranged from family or friends; • law enforcement may not take a "missing person" report; • the person may be in the country illegally; • the person may be an unknown dependent child of unreported missing adults or teens; • the person might be the victim of an undiscovered crime; or • the person may be homeless. Another reason missing persons may not be formally listed as missing is that those over the
age of majority can be "voluntarily missing." Barring evidence of criminality or being a danger to oneself,
privacy and
confidentiality laws generally protect the rights of those who elect to remain out of contact with family or friends. If an adult unreported missing person is located in such an instance, the police are not obligated to inform the family of the missing person's whereabouts. Another example is of children born to
homeless parents. These children are sometimes not registered anywhere and can become victims of crimes such as
human trafficking or
forced prostitution without any of their other relatives or local agencies knowing. A study by professor Kenna Quinet states that the "most successful serial killers know to select the unmissed as victims if they intend to kill for an extended period of time", referring to serial killers targeting transient people, as well as those in institutionalized care, because their absence may not be easily noticed. In
the United States, children in foster care are protected by confidentiality laws; their identity and the fact that they are in the foster care system is private information. In the majority of US states, when foster children go missing their name is not publicly released and, with a few exceptions, child protective services representatives will not speak to the public—in some states, biological parents are not even permitted to contact the
news media about their fostered child going missing. Based on 2002 statistics, of the approximately 585,000 foster children in the US, 20% are missing at any given time, with 98% thought to be runaways and 2% (2,340) unaccounted for. There have also been cases of missing persons reports being accidentally purged from databases, leading to those persons becoming unreported missing. ==Risks==