The act of Alabama HB 56, passed in 2011 is considered to be the strictest anti-illegal immigration bill in the United States. This paper evaluates the impact of this policy on crime, by using the synthetic control method to create a counterfactual Alabama. The results provide suggestive evidence of heterogeneous causal effects of Alabama HB 56 on crime. Compared to the synthetic group, the violent crime rate increased as a response to Alabama HB 56, while there was no significant change in property crime rate after the act. A placebo test was also performed to demonstrate the robustness of the results.