April 24, 2023

Situational crime prevention and offender planning

One of my favorite examples in situational crime prevention (SCP) is a meta-analysis of suicide prevention interventions; Pirkis et al. (2013) find that interventions to prevent jumping deaths (most of the time just fencing at key locations) result in around 88% reduced suicides. There is spillover suicides into local areas, but of much smaller magnitude than the initial reductions at the jumping hotspots, so a clear net reduction.

The typical story in SCP goes like this; offenders are impulsive and hedonistic, so eliminating easy targets prevents impulsive decision making. The proverbial stealing of the apple pie on the open windowsill. Or perhaps a more realistic scenario is the purse on the seat with an open car window.

But this makes it seem like offenders just take advantage of serendipitous circumstances. Many predatory offenders display foraging type patterns (Jacobs, 2010). They go out and look for apple pies (or unlocked cars). I think the case with suicides is likely similar "it contains elements of both longer term planning, as well as more impulsive decision making. People need to intentionally seek out a place to jump. A simple intervention doesn't deter 100% of them, but overall reduces a large proportion of suicides.

The reason I bring this up is in relation to the recent school shootings. There tends to be a level of defeatism in discussion of potential policy changes to prevent such events. Often a point along the line of if an offender is sufficiently motivated, limiting purchasing of types of weapons in a particular state would not have prevented the incident. That gun control laws need to be codified at a national level.

It is true that even if Tennessee passes more strict laws, an offender could take a road trip to Georgia and purchase whatever weapon they want, and Tennessee cannot do anything about it. Some offenders will go to that trouble, many though will not.

Local jurisdictions can enact policies and practices to reduce gun violence. No particular intervention will 100% reduce mass shootings, but state policies can have fairly substantial impacts on violence (Webster et al., 2014).

The perfect should not be the enemy of the good.