In April 2010, the Arizona legislature enacted the Support Our Law Enforcement and Safe Neighborhoods Act. Commonly known as SB 1070, the law created a slate of new criminal offenses and arrest powers covering aliens within Arizona's borders. SB 1070 proved divisive. It inspired copycat legislation in several states, provoked sharp criticism from the legal academy, and-most relevant here- catalyzed a lawsuit by the U.S. Department of Justice seeking a preliminary injunction against the state law on the ground that it was preempted by federal law. Initially, the federal government's litigation prospects seemed dim. One term before SB 1070 reached the Supreme Court, the Justices had upheld an earlier Arizona effort to tamp down on undocumented aliens in the workplace. Doing so, the Court had limned a narrow reach for the preemptive penumbra of federal immigration law. In the SB 1070 oral argument, the Solicitor General seemed to fare poorly, with Justice Sotomayor even suggesting that his central preemption argument was not "selling very well" and that he try "to come up with something else." Yet in June 2012, the Court handed down an opinion giving the federal government "close" to everything it had sought. By a vote of five Justices to three, the Court invalidated three of the four challenged provisions and upheld the fourth subject only on condition that the state satisfied demanding limiting qualifications. What many expected to be a rout in favor of Arizona's position ended instead in a robust affirmation of national authority.
Daniel Abebe and Aziz Z. Huq,
Foreign Affairs Federalism: A Revisionist Approach,
66 Vanderbilt Law Review
Available at: https://scholarship.law.vanderbilt.edu/vlr/vol66/iss3/1