On Saturday, two 12-year-old girls brutally attacked a third girl, stabbing her 19 times and leaving her in the woods. Fortunately, the victim survived. When the girls were arrested, they claimed they were motivated by impressing Slenderman, an urban-legend character popular on Internet sites such as CreepyPasta and others that generally involve user-posted urban legends and scary stories. Slender Man is essentially the 21st-century version of the "Bloody Mary" rhymes of yesteryear -- a scary folklore people continue to embellish on.
But could this myth actually contribute to a horrible crime? The girls reportedly informed authorities that the attack was carried out to prove themselves worthy of Slenderman and establish that he existed. Although 12-year-olds are not adults, reality testing (the ability to distinguish reality from fiction) in the average 12-year-old is reasonably intact. Contrary to comments that children don't distinguish reality from fiction, reality testing actually begins to develop in very young children beginning about age 3. A 12-year-old believing in and attempting to carry out a murder for a fictional character is not developmentally normal.
I have not interviewed either girl and so I can't speak to this specific case. However, from my experience in working with both juvenile delinquents and adult inmates, I see two main possibilities for why Slenderman has become a part of this crime narrative. First, Slenderman could be an excuse to try to shift blame away from the girls themselves. It should come as no surprise that people, including juveniles, who commit crimes do not always tell the truth. Criminals will blame their actions on their parents, society, their peers and, indeed, sometimes even fictional characters. Perhaps most notably, the infamous Son of Sam, David Berkowitz, invented a story about being possessed by a demonic dog incase he was caught for his murder spree to convince authorities that he was insane. In other words, sometimes criminals invent excuses to shift blame from their own actions.
The other possibility is that the girls, indeed, are suffering from a significant cognitive impairment or psychosis. The attorney for one of the girls has suggested she might suffer from mental illness. Whether she is or not will be determined by a court-ordered evaluation, assuming there is one. If the claim of mental illness is true, there certainly are cases of mentally ill individuals fixating on media as a part of their crimes. Examples include John Hinckley Jr.'s fascination with Jodie Foster, or Charles Manson's twisted interpretation of the Beatles song "Helter Skelter." Some criminals claim to have been inspired by religious texts such as the Bible. Just recently in Florida, a 40-year-old woman claimed that a Bible sermon inspired her to attempt to kill her ex-lover's children (one child was drowned). During a 2012 trial, a father claimed that the Bible inspired him to beat his 5-month-old son to death. Whether such individuals were really "inspired" by the Bible or just blaming it after the fact is hard to say. But we wouldn't take seriously claims that Jodie Foster, the Bible or the Beatles are public health threats. Nor do we need to worry about an urban legend like Slenderman.
Some criminals will claim to be inspired by almost anything. Where mental illness comes into play, a person with psychosis can find hidden meanings in the most innocuous of things. Is there something unique or particularly dangerous about Slenderman or the Internet as a whole? No. This case is a single, bizarre case being hyped by news media. In a country of more than 300 million, the occasional bizarre crime is going to happen, and such rare crimes mean nothing at all for society other than that our news media is really good at finding these strange crimes. But we have to remember that violence among youth continues to decline, now at only about 12 percent of what it was two decades ago, and violent crimes among young girls, in particular, remain uncommon. The Internet age has not ushered in a wave of youth violence; If anything, quite the opposite.