Methods: This study used a quasi-experimental design with a difference-in-differences approach to identify the causal impact of MAT vans on local arrest and EMS outcomes.
We evaluated the impact of MAT vans on arrests and overdose rates in four neighborhoods in a northeastern metropolitan city. The treatment group included census block groups containing MAT vans and all surrounding block groups within 0.25 miles. The control group included all other block groups within city limits. We drew on EMS dispatch data and city police arrest records to calculate total city-wide drug charges (n = 8312) and overdose counts (n = 4332) from January 2018 to March 2022. These data were geocoded to assign items to their respective treated or untreated groups. Our main models include quarter and block group fixed effects to estimate a causal effect of the arrival of vans on localized arrest and overdose counts. Since the vans first initiated services on different dates, we test the robustness of our results with two-stage difference-in-differences models.
Results: The analysis indicated that the presence of MAT vans reduced drug arrests by 1.7 per block group per quarter (p < .05), a large effect relative to a mean of 3.17 in treated areas. However, treatment groups saw no significant change in overdose call rates (b = .065, p = .767).
Conclusions and Implications: Our findings suggest that the strategic provision of MAT services using mobile treatment clinics can have a clinically and statistically significant impact on arrest rates in treated areas. This has substantial implications for the development of effective diversion efforts, and is an important contribution to the existing knowledge base since extant research has yielded mixed results for arrest outcomes. These outcomes are meaningful for social work practice, as health equity reflects our ethical commitment to respecting the dignity and worth of individuals. Further, referrals to these services can have a protective effect against the entanglement of clients in the criminal legal system.