A review of Uniform Crime Report (UCR) data from 2001 to 2010 shows gun violence clearly rose on a per-capita basis in Baton Rouge and Houston in the years following Hurricane Katrina. The rise in gun violence in these other cities was not accompanied by similar rises in other major UCR crimes. While the rise in gun violence in Baton Rouge and Houston following Katrina is fairly striking, that does not prove that the flow of evacuees to those cities caused the spike.

Let’s review the data.

First up is the murder rate per 100,000 people for Houston and Baton Rouge from 2001 to 2010, captured in the below chart. This chart shows a bump in the murder rate in Houston between 2005 and 2007 with murder returning to “normal” levels by 2008. Baton Rouge appears to have undergone a larger, more sustained rise in murder from 2006 through 2010. One caveat: the Census Bureau’s population estimates are just that, and they may were likely more imperfect than usual in the wake of Katrina given the huge challenges in tracking and counting large groups of people who had not established permanent residency.

Houston and Baton Rouge Rate of Murder, 2001 – 2010. Source: Uniform Crime Report.

Reviewing the rate of gun assaults (shown below) highlights a similar trend. Gun assaults in both Houston and Baton Rouge rose after Hurricane Katrina, with those levels appearing to fall in both cities by 2010.

Conclusion

This analysis highlights an interesting rise in murder and gun violence in the wake of Hurricane Katrina in two cities that saw large influxes of evacuees. It does not purport, however, to prove any causation between population changes after the hurricane and crime trends, as the data are not sufficient to make such an assessment. Further research into changing violent crime patterns in Houston and Baton Rouge immediately after Katrina could lead to important discoveries that could help prevent future increases after similar disasters throughout the country.