"This systematic review of 22 effectiveness studies relayed evidence of the public health benefits of SIFs for SIF clients as well as to surrounding communities. The strongest evidence suggests that SIFs may help reduce overdose morbidity and mortality and improve access to addiction treatment. An increase in crime, an often-cited concern of SIF opponents, was not observed to be associated with SIFs in most included studies, and crime was actually found to decrease in 2 studies (1 greatest and 1 least suitability of design)."
Levengood, T. W., Yoon, G. H., Davoust, M. J., Ogden, S. N., Marshall, B., Cahill, S. R., & Bazzi, A. R. (2021). Supervised Injection Facilities as Harm Reduction: A Systematic Review. American journal of preventive medicine, 61(5), 738–749. doi.org/10.1016/j.amepre.2021.04.017