Evidence-Based Policing Matrix
Individuals – Small et al. (2019)
Study Reference:
Location in the Matrix; Methodological Rigor; Outcome:
Individuals; Focused; Reactive; Moderately Rigorous; No evidence of effect
What police practice or strategy was examined?
The study examined the effectiveness of removing firearms at the scene of intimate partner violence (IPV) incidents in which offenders used a firearm (i.e., pistol, revolver, or shotgun) in Philadelphia, PA, during 2013. The authors identified 220 first-time IPV incidents in which offenders used a firearm, which included brandishing pistol whipping, or shooting. Police removed a firearm in 52 of these incidents.
How was the intervention evaluated?
The authors compared a treatment group (the 24% of incidents in which firearms were removed) to the remaining 168 offenders (control group). After making the treatment and control groups as comparable as possible based on numerous observed variables (i.e., propensity-score matching), comparisons were made between the two groups on three outcomes: (1) the occurrence of any subsequent IPV after firearm removal, (2) the number of subsequent incidents police responded to, and (3) victim injury in subsequent incidents.
What were the key findings?
Removing firearms at the scene of an IPV incident increased the likelihood of further IPV reports to the police and victim injuries in subsequent incidents. There was also an increased likelihood of any subsequent IPV in the treatment group, but this effect was not statistically significant. The authors suggested that the results may stem from either offenders substituting firearm threats with physical violence, or a change in victims’ willingness to report incidents to the police.
What were the implications for law enforcement?
The authors caution against concluding that firearm removal does not work, noting that the study was unable to systematically analyze certain outcomes, such as a reduction in homicides due to the small number of IPV-related homicides. Furthermore, it remains unclear whether the observed increase in subsequent IPV reports to the police and subsequent injuries to victims is attributable to heightened physical aggression by offenders or to victims' increased willingness to report incidents. These findings underscore the complex dynamics between firearm removal and subsequent IPV incidents.
Where can I find more information about this intervention, similar types of intervention, or related studies?