Arizona Senate Bill 1070 requires law-enforcement officers to verify the citizenship of individuals they stop when they have a “reasonable suspicion” that someone may be unlawfully present in the United States. Critics of the law fear it will encourage racial profiling. Defenders of the law point out that the statute explicitly forbids most forms of racial profiling. By drawing on the lessons learned in the domain of antidiscrimination law, we discuss how social psychological research can inform this debate and illuminate challenges associated with fair enforcement of the statute. We conclude that the Arizona law, paired with a lack of comprehensive training and ineffective testing procedures for detecting discrimination, will likely result in many Latinos being illegally targeted on the basis of their race. While certain actions, such as effective training and oversight, may help mitigate discrimination, these safeguards are not likely to completely eliminate biased outcomes.