Arizona v. the United States

Not since the American Civil War has State power vis a vis federal power so elevated.

Holding: The lower courts erred in holding that Section 2(B) of Senate Bill 1070 - which requires police to check the immigration status of persons whom they detain before releasing them and which allows police to stop and detain anyone suspected of being an undocumented immigrant – should not go into effect while its lawfulness is being litigated because it is not sufficiently clear that the provision is preempted. Section 3 – which makes it a state crime for someone to be in the United States without proper authorization – is preempted because Congress left no room for states to regulate in that field, or even to enhance federal prohibitions. Section 5(C) -which makes it a state crime for undocumented immigrants to apply for a job or work in Arizona – is preempted as imposing an obstacle to the federal regulatory system. Section 6 – which authorizes state law enforcement officials to arrest without a warrant any individual otherwise lawfully in the country, if they have probable cause to believe that the individual has committed a deportable offense – is preempted because whether and when to arrest someone for being unlawfully in the country is a question solely for the federal government.
Judgment: Affirmed in part, reversed in part, and remaned., 5-3, in an opinion by Justice Kennedy on June 25, 2012. Justices Scalia, Thomas and Alito each filed opinions concurring in part and dissenting in part. (Kagan, J., rescued)

Docket No.	Op. Below	Argument	Opinion	Vote	Author	Term
11-182	9th Cir.	Apr 25, 2012 Tr.Aud.	Jun 25, 2012	5-3	Kennedy	OT 2011