The problem. Homicide and gun violence are serious public health and safety problems. People who are directly or indirectly exposed to violence can develop many problems, including post-traumatic stress disorder, depression, and anxiety. Studies have shown that they are more likely to drop out of school, increase their sexual activity, run away from home, and become criminals than those not exposed to violence. While homicide and gun violence are most common among young men who belong to gangs and other risky social networks (i.e., drug-dealing groups, drug users who exchange needles, stick-up crews, firearms trafficking rings, narcotics distribution rings, etc.)—the majority of people in high-risk neighborhoods where gangs are active are not shot or murdered.
Scholar perspective. Andrew V. Papachristos, PhD, wanted to understand why some people in risky social networks were killed or exposed to gun violence while others were not. And he wanted to be able to do something to help stop homicide and violence.
As a teenager in Chicago, he started a nonprofit organization that mediated disputes between gang members, and helped those who wanted to leave a gang do so. "I was fascinated with crime and street gangs," he said. Thinking he would work in law or law enforcement, Papachristos studied criminal justice at Loyola University of Chicago. After taking courses in sociology, though, he became interested in the field, and then he had to choose between joining the Oak Park (Illinois) Police Department or going on to graduate school.
Papachristos chose graduate school, earning MA and PhD degrees in sociology from the University of Chicago. In 2007, he joined the sociology faculty at the University of Massachusetts, Amherst, as an assistant professor. But he found the research in his areas of interest—violence, homicides, and neighborhoods—to be too removed from the everyday realities of the communities in which he worked.
"When I look at these case files, we're talking about dead bodies. It's a real problem. Public health and public policy should have more of an interest in this," he said. "Homicide is the third leading cause of death in men, up there with cancer. But it doesn't get the same play in medical or public health journals." That is because sociologists do not know how to communicate with public health practitioners and policy-makers.
To "unravel the way crime spreads" within and between groups of people, and to pinpoint who is most at risk for violence, Papachristos had begun using social network analysis: studying the connections between people and groups and how these connections influence behavior. These data could be used to design better interventions to stop violence. But Papachristos quickly realized that in order to be effective, he needed to learn the vocabulary of public health and policy communities.
The Robert Wood Johnson Foundation Health & Society Scholars program helped Papachristos do that, by introducing him to the world of public health. In 2010, Papachristos began his two-year interdisciplinary fellowship at Harvard University, one of the six universities participating in the Health & Society Scholars program. For more information on the program, read the Program Results Report.
Integrating sociology and public health. With competitive research grants from the Health & Society Scholars program and the Harry Frank Guggenheim Foundation, Papachristos studied the role of social networks on the diffusion of gun violence in Chicago and Boston.
In Chicago, he studied the association between exposure to and the risk for homicide among people in a high-crime Black community. Using five years of homicide and police records, he analyzed the social networks of 3,718 people and found that 41 percent of all gun homicides occurred within a social network containing less than 4 percent of the neighborhood's population. He concluded that understanding these social networks may improve the ability to predict which people will be victims of homicide within disadvantaged communities.
In Boston, Papachristos and colleagues combined police data and records of gunshot injuries to study the relationship between a person's position in a high-risk social network and the probability of being a gunshot victim among 763 people in one of the city's Black communities. In an article in the Journal of Urban Health (Vol. 89(6), 2012), they reported that 85 percent of the gunshot injuries occurred within a single social network. They concluded that the closer a person is to a gunshot victim's social network, the greater the probability that person will be shot.
"There's something about these networks," said Papachristos. "As we understand how violence is distributed, we can direct resources that way." For example, to prevent retaliation, the message to put down the gun would be most effective if delivered after a shooting to the associates of someone who was shot.
Papachristos and colleagues also conducted a study in Chicago of whether homicide in a child's community environment altered classroom behavior and functioning. For this study, they used police data and assessments done as part of the Chicago School Readiness Project, which measured school readiness in 496 preschoolers participating in 18 Head Start sites. In assessments of children within a week of a homicide near their home, Papachristos found that the children had less attention and impulse control and lower pre-academic skills (American Journal of Public Health, Vol. 102(12), 2012). Exposure to homicide also caused acute psychological distress among parents, which may be how violence affects young children.
After completing his Health & Society fellowship in 2012, Papachristos joined the faculty at Yale University as an associate professor of sociology. He credits the RWJF program with enabling him to become a "broader thinker" and exposing his research to many people in academia, two factors that he believes contributed to his career advancements and recognition. "I had a very traditional sociology trajectory," he said, but he now brings "sociology to public health."
Reducing violence through research and consulting. Under a National Science Foundation Early CAREER Program that began in 2012, Papachristos is expanding the research he began as a Health & Society scholar. Using police data from Chicago, Boston, and Oakland, and at least one other city, he is studying: (1) the effect of individual criminal and noncriminal networks on homicide and violent victimization, and (2) groups/gangs and how intergroup relationships and neighborhood characteristics contribute to murder and non-fatal violence.
Papachristos is also involved as principal investigator or co-investigator in the evaluation and implementation of several violence reduction strategies, including the U.S. Department of Justice's Safe Neighborhoods Project and the MacArthur Foundation's Chicago Violence Reduction Strategy. Both initiatives aim to reduce gun violence and gang crimes, and Papachristos' role in this work includes social network analysis to identify target areas and to coordinate prevention activities. Papachristos is also using social network analysis for a U.S. Department of Justice violence prevention initiative in New Haven, Bridgeport, and Hartford, Conn.
Results from Papachristos' social network analyses help police and other officials in these cities find better ways to combat violence. In Chicago, for example, police and city officials work with community members, service providers, and employers to deliver a focused deterrence message. Police let gang members in areas most affected by violence know that they are watching them and will hold them accountable for the next shooting. At the same time, service providers offer job training and transportation to interviews to try and help break the cycle of violence. Since many of the gang members are felons, the training is with employers who have agreed to hire felons.
"It's the first time a lot of these cities are looking at the problem this way," said Papachristos. "It's a 'do more good' strategy."
RWJF perspective. RWJF created the Health & Society Scholars program in 2001 to build the field of population health. "There is a growing recognition that health is the result of the interaction of multiple factors including socioeconomic and physical environmental factors and health behaviors," said Pamela G. Russo, MD, MPH, senior program officer. "The evidence shows that these types of factors play a much larger role in determining health at the population level than do the traditionally considered health care and biological determinants of health. The program seeks to integrate paradigms and knowledge from a variety of disciplines to develop an understanding of how these determinants affect the health of populations, and thereby to design interventions with greater power to reduce health disparities," said Russo.