1. Despite initial characterization in the press as a split decision, the Supreme Court's ruling in Arizona v. United States is a significant victory for opponents of the Arizona immigration law.
2. The Court upheld lower court rulings striking down key provisions of an Arizona law that would have (a) criminalized failure to comply with immigration registration requirements, (b) criminalized illegal immigrants seeking employment, (c) provided authority to state law enforcement officers to make warrantless arrests of certain aliens suspected of being in the U.S. illegally.
3. The Court upheld, contrary to lower court decisions, a provision of the Arizona law that allows a state law enforcement officer to consult with federal immigration officials regarding the status of an otherwise lawfully detained individual when the officer suspects such individuals of being in the U.S. unlawfully. The Court made clear, however, that it expects this authority to be narrowly construed and explicitly reserved the right to reconsider the provision in the future.