Journal of Urban Health

, Volume 86, Issue 4, pp 511-523

First online:

Open Access This content is freely available online to anyone, anywhere at any time.

The Effect of Urban Street Gang Densities on Small Area Homicide Incidence in a Large Metropolitan County, 1994–2002

  • Paul L. RobinsonAffiliated withCharles Drew University of Medicine and ScienceUniversity of California, Los Angeles Email author 
  • , W. John BoscardinAffiliated withUniversity of California, San Francisco
  • , Sheba M. GeorgeAffiliated withCharles Drew University of Medicine and Science
  • , Senait TeklehaimanotAffiliated withCharles Drew University of Medicine and Science
  • , Kevin C. HeslinAffiliated withCharles Drew University of Medicine and ScienceUniversity of California, Los Angeles
  • , Ricky N. BluthenthalAffiliated withUrban Community Research Center, Sociology Department, California State University, Dominguez HillsHealth Program, Rand Corporation


The presence of street gangs has been hypothesized as influencing overall levels of violence in urban communities through a process of gun–drug diffusion and cross-type homicide. This effect is said to act independently of other known correlates of violence, i.e., neighborhood poverty. To test this hypothesis, we independently assessed the impact of population exposure to local street gang densities on 8-year homicide rates in small areas of Los Angeles County, California. Homicide data from the Los Angeles County Coroners Office were analyzed with original field survey data on street gang locations, while controlling for the established covariates of community homicide rates. Bivariate and multivariate regression analyses explicated strong relationships between homicide rates, gang density, race/ethnicity, and socioeconomic structure. Street gang densities alone had cumulative effects on small area homicide rates. Local gang densities, along with high school dropout rates, high unemployment rates, racial and ethnic concentration, and higher population densities, together explained 90% of the variation in local 8-year homicide rates. Several other commonly considered covariates were insignificant in the model. Urban environments with higher densities of street gangs exhibited higher overall homicide rates, independent of other community covariates of homicide. The unique nature of street gang killings and their greater potential to influence future local rates of violence suggests that more direct public health interventions are needed alongside traditional criminal justice mechanisms to combat urban violence and homicides.


Violence Injury Mortality Intentional injury mortality Homicide Gangs Street gangs Crime Youth violence Health disparities