Table 2.

Unadjusted difference-in-differences estimates for crime outcomes (units are crimes per square mile).

	Pre-period mean	Post-period mean	Mean difference
Felony assaults
Control sites	1.86	2.63	0.77***
Treated sites	1.71	2.13	0.42***
Difference-in-differences	0.15***	0.50	−0.35***
Burglaries
Control sites	12.07	12.86	0.79***
Treated sites	15.43	13.78	−1.65***
Difference-in-differences	−3.36***	−0.92	−2.44***
Robberies
Control sites	1.18	1.68	0.50***
Treated sites	1.01	1.22	0.21*
Difference-in-differences	0.17	0.46***	−0.29***
Thefts
Control sites	9.64	10.29	0.64***
Treated sites	10.49	10.65	0.16
Difference-in-differences	−0.85***	−0.36***	−0.48***
Motor vehicle thefts
Control sites	2.48	2.58	0.10***
Treated sites	2.25	1.97	−0.28
Difference-in-differences	0.23***	0.61	−0.38**

^*P < 0.05,

^**P < 0.01,

^***P < 0.001, based on two-sample Wilcoxon rank-sum (Mann-Whitney) test.

Sample sizes: pre-period (treatment: 12,928/control: 11,472); post-period (treatment: 3232; control: 2868).