Oral argument: Apr. 25, 2012
Appealed from: United States Court of Appeals for the Ninth Circuit (Apr. 11, 2011)
In 2010, Arizona enacted the Support Our Law Enforcement and Safe Neighborhoods Act, which creates state immigration offenses and expands local police officers’ immigration law enforcement authority. The United States sued Arizona in federal district court, arguing the state law was preempted by federal law, and sought a preliminary injunction to prevent the state law from taking effect. The district court granted a preliminary injunction with respect to four provisions of the Arizona law and the Ninth Circuit affirmed. Petitioners, the State of Arizona and the Governor of Arizona, Janice K. Brewer, argue that federal law does not preempt its statute because Arizona’s statute merely creates a formal cooperative relationship between federal and state officers to implement federal laws. Respondent, the United States, asserts that implementation of the statute would infringe upon the Executive Branch’s exclusive authority to regulate immigration, and is therefore invalid.