It's easy to dismiss something shocking and horrific as a random act of brutality.
But when a 15 year-old girl was gang raped last Saturday behind a high school in Richmond, Calif., it was an extreme example of behavior that is all too common, according to some experts' chilling research.
Around 9 p.m. that evening, a teenager left her homecoming dance at Richmond High School. Friends assumed she was heading home early. It wasn't until nearly midnight, after she had been repeatedly raped and beaten for over two hours that she was discovered, bloodied and unconscious, under a bench on school grounds.
Police have said that as many as 10 people participated in the crime, while another 10 looked on without intervening or calling for help.
How does such a thing happen? Certainly school officials and security guards shoulder some of the blame for a lack of vigilance. Perhaps the onlookers were paralyzed by a psychological condition called "the bystander effect."
But beneath it all is a grim reality: gang rape among troubled youth in urban areas is common.
In interviews with teenagers between ages 13 and 19 living in poor and violent neighborhoods in St. Louis, Mo., sociologist Jody Miller found that incidents of gang rape were alarmingly high.
Of the 75 kids Miller interviewed, 45 percent of boys admitted to "running train" — local slang for gang rape. About one half of girls reported being sexually assaulted and one-third said they'd been attacked more than once.
"What concerns me is that this is relatively common," Miller said, whose research was published last year in the book Getting Played: African American Girls, Urban Inequality, and Genderd Violence (New York University Press).
"Among the boys I interviewed, they did not conceptualize what they were doing as sexual assault.
"This incident in California echoed so much of what my own research has said," she added.