A team of scientists has confirmed something your parents probably warned you about as a teenager — that hanging out with the wrong crowd can be dangerous.
A study by two Yale University sociologists titled Network Exposure and Homicide Victimization in an African American Community found that some accepted metrics of vulnerability to becoming a homicide victim — such as race, membership in a gang or physical proximity to a murder victim, are less important than one's social network.
In other words, it's all about whom you know.
"[Victimization] is not simply a function of spatial proximity or of individual risk factors such as age, race, gender or gang affiliation, but also of how people are connected, the structure of the overall network, the types of behaviors occurring in the network and an individual's position in the overall structure," the authors write in the paper published Thursday in the American Journal of Public Health.
Andrew Papachristos and Christopher Wildeman studied homicide and police records from 2006 to 2011 to look at 3,718 high-risk individuals living in a 6-square-mile area of Chicago with some of the city's highest murder rates. They modeled the odds of one becoming a gunshot homicide victim by individual characteristics, including network position, and indirect exposure to homicide.
Papachristos and Wildeman concluded that "Network exposure to homicide was strongly associated with victimization: the closer one is to a homicide victim, the greater the risk of victimization."
The authors determined that 41 percent of all homicides involved just 4 percent of a neighborhood's population.
"[Homicide] is socially contagious, and associating with people engaged in risky behaviors — like carrying a firearm and engaging in criminal activities — increases the probability of victimization," Papachristos and Wildeman said.
Within the network, simply being identified as a gang member by police didn't significantly increase the chances of being a victim, they said.
The authors found that for each degree of separation from a homicide victim, one's odds of also being murdered went down by 57 percent.
"Generally, you can't catch a bullet from just anyone," Papachristos, a Chicago native, tells The Chicago Sun-Times. "Your relationship with the people involved matters. It's not unlike needle sharing or unprotected sex in the spread of HIV."
The newspaper quotes Chicago Police Department spokesman Adam Collins as saying the department was "using variations of Dr. Papachristos' research to ensure we reach out to individuals at the greatest risk for violence."
Papachristos said police departments in California and Connecticut were working on similar strategies to reduce crime.