How environmental stress increases violent crime: Study

Understanding the social contexts of violent crime remains controversial among researchers and policymakers alike. A recent article published in Crime and Delinquency (2021) discusses common social contexts in four cities (Houston, TX, Baltimore, MD, Jackson, MS, Wilmington, DE). The researchers applied two approaches: the first compared each city’s health outcomes with national county-level data, and the second examined correlates for crime within the four cities.

Results found several social factors that correlated with crime, including single-parent homes, insufficient food resources, poor sleep quality, residential segregation, and more. Interestingly though, all four cities had lower suicide rates than the national average. At the community-level, researchers found that factors such as unemployment, median household income, and population density all correlated with crime as well. While communities with higher violent crime rates did tend to have higher proportions of Black residents, race per se did not appear correlated with violent crime. Rather, class-related issues seemed to override any individual impact of race on crime.

Study Methods 

The four cities examined were Houston, TX, Baltimore, MD, Jackson, MS, and Wilmington, DE, which were selected as part of a broader study to examine motivations of youth gun possession in cities with Historically Black Universities. These cities have histories of high violent crime as well as wide geographic diversity. The cities were examine using two analyses: the first compared the four cities against national rates of social stress indicators, and the second examined communities (at the zip code-level) within these four cities to see what factors were most associated with crime.

In order to look at public health-related factors, the authors used the County Health Rankings Dataset (CHRD), a dataset that is compiled yearly by the Robert Wood Johnson Foundation and the University of Wisconsin Pollution Health Institute. The data provides an understanding of the collective health of its members (e.g., mortality and morbidity) and those factors found to impact future health (e.g., social and economic factors, physical environment). Using this dataset, researchers were able to determine the level of health in over 3,000 U.S. counties.

Research has demonstrated that crime is concentrated at relatively few locations, potentially explaining some of the intra-community variation in crime. Thus, the authors sought to examine within-community variation to see which neighborhood (zip code-level) features were most associated with violent, property, and drug crime. This part of the analysis used data from two sources: the Area Deprivation Index (ADI) which provides state and national level rankings of communities based on an analysis of education, employment, housing, and income; and the Livability Index, which is compiled from US Census Data and FBI crime data. From this, the authors were able to compile information on violent crime, property crime, mean household income, unemployment, academic test scores, percent Black residents, and population density.

Results

Results found several social factors that impacted violent crime, including single-parent homes, insufficient food resources, poor sleep quality, residential segregation, and more. At the community-level, factors such as unemployment, median household income, and population density were also correlated with crime. It is important to note though, that correlates of crime are not necessarily causal but may be indicative of other neighborhood-level factors, such as wider public health issues.

Based on past literature, physical and mental health outcomes are likely affected by exposure to adverse environments, which are exacerbated by poverty and social disorganization. For example, patients living in economically deprived neighborhoods tend to have poorer depression and anxiety treatment outcomes and require lengthier interventions, as they may have less access to clinical care than comparable urban and rural areas. They also might be more likely to reside in single-parent households, which has also been found in prior research.

One counterintuitive finding of the current study was that all four cities had lower suicide rates than the national average. This is perplexing, and suggests that violent crime and suicide likely exist along divergent stress paths. Nonetheless, this result is consistent with a recent cross national study which found that suicides are higher in wealthier nations, whereas homicides were more common in countries with higher income inequality.

Additionally, communities with higher violent crime rates had higher proportions of Black residents, but race on its own was not correlated with violent crime. Regardless, the findings are consistent with other research. These results revealed that class-based issues involving economic disadvantage and social stress were more salient than race when it comes to predicting crime. To examine this further, authors conducted a multivariate analysis that looked at the variation within cities, which did not substantially change results. Property crimes were correlated with state ADI, national ADI, and unemployment, and violent crimes were correlated with unemployment, median household income, academic test scores, and population density. Percent Black reached statistical significance, but the effect size was so small that it was judged as trivial and potentially noise.

Discussion

The results suggested that economic and health-related factors (e.g. lack of sleep, mental health issues, substance abuse problems) correlated with both violent and property crime. Throughout the findings this was a consistent outcome, and it is also consistent with prior literature. When looking at within-community variation, results  did not change substantially. Violent crime was correlated with multiple community stress factors, while property crime was associated with unemployment and ADI. Interestingly, suicide was less common in high-crime areas, suggesting that the stressors driving violent crime and stressors driving suicide are likely different.

Taken together, the results suggested that property crimes were more narrowly related to economic factors, whereas violent crimes were related to more general community stress. Race was not correlated with either crime outcome, which suggested that community factors related to stress and class are correlated with crime perpetration, rather than race itself.

It is important to note that the findings are based on correlation and, as such, no causal conclusions can be drawn. Regardless though, the findings did provide evidence for some economic and social stress indicators that were consistent across four high violent crime cities. These particular factors may be particularly useful for dictating public policy efforts focused on crime reduction, which remains an important task.