When Habitat for Humanity announced in March that it had started putting volunteers to work tearing down houses, instead of building them, preservationists fretted about the role wrecking balls would play in cleaning up the mess created by the collapse of the housing market. But according to a study by University of Pennsylvania epidemiologist Charles Branas, the rise of demolition as a response to foreclosure and abandonment carries implications that extend far beyond the realm of preservation, into the domain of public health.
Branas has found compelling evidence of a strong link between increased rates of aggravated assaults and a rise in the number of vacant lots in an urban area. By overlaying police data on aggravated assaults in particular geographic areas between 2002 and 2006 with corresponding census demographics data and vacant property records, Branas and his team of Penn researchers discovered that total assaults in a given set of blocks increased by 18.5 percent for every increase in vacancy in that area. The positive correlation was stronger for gun assaults, which increased by 22.4 percent with each new vacant lot, than for non-gun attacks, which rose by 14.8 percent for every increase in vacancy.
Branas, who controlled for sociodemographic characteristics such as crowding, race, ethnicity, income, unemployment, education, home ownership, family headship, concluded that vacant properties were associated with “increased assaults independent of other indicators of disadvantage.” In 2006, the final year of the four-year study, the city of Philadelphia counted 20,000 vacant properties and 406 homicides.
“Vacant lots far outpace these other indicators of aggravated assault,” said the epidemiologist, a presenter at a National Vacant Properties Campaign conference held this week in Louisville. The conference will conclude this evening.
While researchers have long known that urban neighborhoods with a proliferation of vacant lots often suffer from high crime rates, Branas’ research is the first to quantify a relationship between vacant lots and urban violence. The study’s findings confirm what was already felt by crime-scarred residents of New Orleans, where I live. The Crescent City bears the dubious twin distinctions of having the country’s highest per capita murder rate and second-highest vacant lot rate. In 2008, 64 people were killed per 100,000 residents, according to FBI data released yesterday. Data released earlier this year showed that a startling 35 percent of unique addresses in the city – 66,000 lots – are vacant.
Ariella Cohen is Next City’s editor-in-chief.