If you’re won­dering who else in the United States might fit a “pro­file” of becoming a mass killer, just look around: They are every­where, and they’re most likely harmless.

Fright­en­ingly, we have little idea about what sep­a­rates those who ponder com­mit­ting slaughter from those who go through with it. Experts say that risk fac­tors, such as social iso­la­tion and rejec­tion, are found in many people across the United States, a country shaken by the mas­sacre at Sandy Hook Ele­men­tary School in New­town, Con­necticut, on Friday, in which 20 chil­dren and six adults were killed.

Adam Lanza, 20, the shooter, whom police say turned the gun on him­self Friday, attended the school. He has been described as quiet and socially awk­ward. There are still few details of what could have moti­vated his actions.

The truth is that there are many people who have all the symp­toms, and don’t get the dis­ease,” said Jack Levin, pro­fessor of soci­ology and crim­i­nology at North­eastern Uni­ver­sity in Boston. “They may be loners, and strange and angry and have access to firearms, but they don’t hurt anyone.”

Read the article at CNN →