Indicator SC.1.a Violent crimes
Descriptive Title: Number and rate of violent crimes
Geographic Unit of Analysis: Census tract
Why Is This An Indicator Of Health and Sustainability?
Physical assaults, homicides and rapes/sexual assaults are direct and adverse health outcomes for a community. In many low income communities, homicides account for the largest number of years of avoidable life lost. Witnessing and experiencing community violence causes longer term behavioral and emotional problems in youth.a,b Finally, community violence also impacts the perceived safety of a neighborhood, inhibiting social interactions and adversely impacting on social cohesion.c Parental concerns about neighborhood crime strongly influence their willingness to allow their children to actively commute (e.g. walk or bike) to school, influencing children’s levels of physical activity.d
Interpretation and Geographic Equity Analysis
The World Health Organization defines violence as: the intentional use of physical force or power, threatened or actual, against oneself, another person, or against a group or community that either results in or has a high likelihood of resulting in injury, death, psychological harm, maldevelopment or deprivation.e
This indicator provides one limited measure of violence: the number and rates of homicides, physical assaults, and rapes reported to the San Francisco police department. Between 2005 and 2007, the rate of violent crime as measured by these three indicators was higher in the eastern neighborhoods of the Tenderloin, the South of Market, the Mission, Potrero Hill, Visitacion Valley and Bayview , compared to the northern and western neighborhoods of San Francisco. Certain areas such as Golden Gate Park, industrial areas of Bayview, and the Financial District, have comparatively high rates of violent crime due to low residential population density that do not include estimates of daily visitors to the area.. Other neighborhoods, such as the Civic Center, Mission, and South of Market, have both high numbers of violent crime incidents and high rates of violent crime relative to population density.
While data and statistics profile the trends of violence, they do not explain the factors that influence its occurrence. Violence is rarely caused by a single risk factor but rather by the presence of multiple risk factors and absence of protective (or resiliency) factors. Risk factors are traits or characteristics that increase the relative risk of an individual or community being affected by or perpetrating violence. Resiliency factors are traits or characteristics that protect an individual or community from violence.
Risk factors for violence include: poverty and economic disparity, illiteracy and school failure, alcohol and other drugs, firearms, negative family dynamics, mental illness, incarceration/reentry, community deterioration, discrimination and oppression, power and control, media violence, experiencing and witnessing violence, and, gender socialization. Resiliency factors from violence include: economic capital, meaningful opportunities for participation, positive attachments and relationships, good physical and mental health, social capital, built environment, services and institutions, emotional and cognitive competence, artistic and creative opportunities, ethnic, racial, and intergroup relations, and media/marketing.f
As noted by the Prevention Institute, "A public health approach to violence is rooted in the understanding that criminal justice alone cannot solve the problem of violence…Utilizing public health principles promotes broader, more lasting solutions to the violence problem. Such an orientation is essential because "no mass disorder afflicting mankind is ever brought under control or eliminated by attempts at treating the individual." g
Various elements of the built environment, which vary by geography, can promote or inhibit violence prevention in a community. For example, “poor and inadequate housing is associated with increased risk for violenceh and psychological stress.i Alternatively, the availability of safe and affordable housing can reduce stresses associated with living in unsafe, noisy, or overcrowded conditions or not being able to secure housing. Decisions about housing and its design can promote social interaction, community stability, and build a solid tax base to fund needed services, including violence prevention. Reliable and affordable transportation can ensure that people have access to jobs and services. Zoning can also influence the availability of beneficial products such as books and school supplies, sports equipment, arts and crafts supplies, and other recreational items as well as limit availability or lack, of potentially harmful products such as tobacco, firearms, alcohol, and other drugs can also have an impact on violence within a community."f Collectively, many of the other HDMT indicators illustrate the distribution of violence prevention elements across the city and within neighborhoods.
Methods
The data for these indicators comes from police incident reports written by the San Francisco Police Department for crimes reported during the 2005-2007 time period. The maps show those incidents with addresses it recognizes, or where the location was known to the victim. Sometimes, a crime has no specific location. For example, if someone was assaulted on MUNI the location is "Unknown" or if the victim cannot specify the location. Other times, the address cannot be located by the computer mapping system, and then the location is "Location not Found". Other incidents which happened outside the locality, but reported to the San Francisco Police Department are classified as "Out of Town."
Crimes were aggregated by census tract to present on the maps. Rates per thousand residents were calculated by dividing the number of incidents by the number of people residing in each census tract.
Limitations
Measuring the incidence of crime is extremely difficult. Much crime goes undetected and some crimes are not reported to police. Crimes that go undetected and unreported cannot be counted. Finally, the police themselves may, for various reasons, not record something as a crime, or inaccurately report something as a crime when it is not.
Underreporting and statistical undercount influence the degree to which these data are reflective violent crimes, particularly rape and sexual assault. Victims may not file reports because of shame or fear of retribution, and/or insensitivity of law enforcement and court personnel. Underestimation may also occur because rape and sexual assault injuries may not always be captured by hospitalization and death statistics.
Some violent crimes are reported but without a specific location. Violent crimes without a location are not included on the maps and tables above. Additionally, some violent crimes may have been committed outside of the city limits, but reported in the City.
Data Source
Crime data from San Francisco Police Department, 2005-2007.
Population Data Source: Applied Geographic Solutions, Inc. Spring 2007 Update: Current Year Estimates. Methodology available at: http://www.appliedgeographic.com/library.html.
Map and table created by San Francisco Department of Public Health, Environmental Health Section using ArcGIS software.
Map data is presented at the level of the census tract. The map also includes planning neighborhood names, in the vicinity of their corresponding census tracts.
Table data is presented by planning neighborhood. While planning neighborhoods are larger geographic areas than census tracts, census tracts do not always lie completely within a planning neighborhood. SFDPH used ArcGIS software and a dasymetric mapping technique to attribute Census block group data to residential lots. We then assigned residential lots to planning neighborhoods to calculate Census population totals within the neighborhoods.
Detailed information regarding dasymetric mapping, census data, geographic units of analysis, their definitions, and their boundaries can be found at the following links:
http://www.thehdmt.org/etc/Geographic_Units_of_Analysis.pdf
http://www.thehdmt.org/data_map_methods.php
Perez-Smith AM, Albus KE, Weist MD. 2001. Exposure to violence and neighborhood affiliation among inner-city youth. J Clin Child Psychol 30(4):464-72.
Ozer EJ, McDonald KL. 2006. Exposure to violence and mental health among Chinese American urban adolescents. J Adolesc Health 39(1):73-9.
Fullilove MT, Heon V, Jimenez W, Parsons C, Green LL, Fullilove RE. 1998. Injury and anomie: effects of violence on an inner-city community. Am J Public Health 88(6):924-7.
Kerr J, Rosenberg D, Sallis JF, et al. Active commuting to school: Associations with environment and parental concerns. Med Sci Sports Exerc. 2006;38(4):787-79.
WHO Global Consultation on Violence and Health. 1996. Violence: a public health priority. Geneva: World Health Organization (document WHO/EHA/SPI.POA.2).
Prevention Institute. 2005. A Lifetime Commitment to Violence Prevention: The Alameda County Blueprint. Available at: http://www.preventioninstitute.org/alameda.html. Retrieved 7/6/2006.
- Prevention Institute. 1999. Cultivating Peace in Salinas: A Framework for Violence Prevention. Available at: http://www.preventioninstitute.org/vppubs.html#reports. Retrieved 12/6/2006.
PolicyLink. 2002. Reducing health disparities through a focus on communities. Oakland, CA: A PolicyLink Report.
Geronimus A. 2001. Understanding and eliminating racial inequalities in women's health in the United States: the role of the weathering conceptual framework. JAMWA 56(4):133-136.