Evidence-Based Policing Matrix
Micro Places – Kyvsgaard et al. (2022)
Study Reference:
Location in the Matrix; Methodological Rigor; Outcome:
Micro places; Focused; Proactive; Very Rigorous; No evidence of effect
What police practice or strategy was examined?
This study evaluated a chemical property marking program implemented in the North Zealand, Denmark in early 2019 through mid-2020. This intervention was based on the chemical property marking kit program experiment conducted in Arahus, Denmark in 2017. Treatment households (n = 4,000) received a letter from the District Police Chief with information about the high rate of burglary in their area and offered the household a free property marking kit if they registered for the experiment. The free property marking kits instructed households to post warning stickers on windows, post boxes, entrances, and doors, and to register their unique identification code in an online database. Placebo households (n = 4,000) received a letter from the District Police Chief describing the high rate of burglary in their area and were provided recommendations on how to reduce household risk.
How was the intervention evaluated?
A randomized experiment was conducted to evaluate the intervention. A 12,000-household sample was selected for participation in the study. Each household was randomly allocated into one of three groups: treatment, placebo, or control. Treatment households received a letter about burglary in their area and were offered the free property marking kit, whereas the placebo households were only sent a letter about how to lower their risk of victimization. Control households were never contacted. To evaluate the intervention, the researchers examined burglary data for a 15 ½ month follow-up period (May 15, 2019-August 2020). The researchers also conducted a process evaluation to understand if treatment households requesting the marking kits had followed instructions to post warning stickers.
What were the key findings?
There were no significant differences in burglary rates between treatment (4.6%) and control households (4.9%), or between placebo (4.9%) and control (5.1%) households. Results indicated that only a small portion of the treatment households posted the warning stickers during their process evaluation. Even after sending reminder letters, only 29% of treatment households posted the warning stickers, while 27% of treatment households registered for the experiment but never posted the stickers, and 44% of treatment households never registered. When comparing treatment households that posted stickers to control households, the researchers found a reduction in the risk of burglary victimization (3.7%), however, this was reduction was not statistically significant.
What were the implications for law enforcement?
The authors conclude that offering property marking kits to households is unlikely to impact their risk of burglary, however, this may be due to low rates of compliance. When warning stickers are posted as part of the property marking program, risk of victimization may be reduced, but likely to a small degree. Moreover, receiving a letter with information on the high rate of burglaries in one’s area and recommendations for how to lower the risk of burglary victimization is likely to have no effect on a household’s risk of future burglary.
Where can I find more information about this intervention, similar types of intervention, or related studies?