Testing a promising homicide reduction strategy: re-assessing the impact of the Indianapolis “pulling levers” intervention

Since the publication of analyses suggesting the significant impact on youth homicide of the Boston “pulling levers” intervention, a series of studies of similar strategies have indicated promise in reducing homicide and gun assaults. One of these studies was an assessment of a pulling levers strategy in Indianapolis, where trend analyses indicated a significant reduction in homicide following the intervention, while six other similar Midwestern cities did not experience a significant decline in homicide. We re-assess the results of the Indianapolis study by disaggregating the offenses into gang- and non-gang homicides. Given that the pulling levers program focused on influencing gangs and networks of chronic offenders, the impact of the intervention should be more apparent for gang homicides than for non-gang homicides. Alternatively, should the impact be similar for non-gang homicides, then it is more likely that the downward trend would be caused by unmeasured external forces. Coefficient-difference tests relying on estimates obtained from autoregressive integrated moving average (ARIMA) time–series models indicate that gang homicides declined significantly more than did non-gang homicides following the Indianapolis intervention. These findings suggest ‘something happened’ to gang homicides that did not happen to non-gang homicides, which adds further support that the pulling levers initiative was the driving force behind the overall reduction in homicide in Indianapolis.

Fracture patterns on the infant porcine skull following severe blunt impact

The objective of this study was to document patterns of fracture on infant porcine skulls aged 2-28 days (n = 57) because of a single, high energy blunt impact to the parietal bone with rigid (nondeformable) and compliant (deformable) interfaces. Fracture patterns were mapped using Geographic Information System software. For the same generated impact force, the rigid interface produced more fractures than the compliant interface for all ages. This study also showed that this increased level of impact energy versus an earlier study using a lower energy resulted in new sites of fracture initiation and also caused previously defined fractures that propagate into an adjacent bone. Several unique characteristics of bone and diastatic fracture were documented as a function of specimen age, impact energy, and interface. These data describe some baseline characteristics of skull fracture using an animal model that may help guide future studies from forensic case files.