[JURIST] The US Supreme Court [official website] on Monday ruled 5-3 [opinion, PDF] that three provisions of Arizona’s controversial immigration law [SB 1070 materials; JURIST news archive] are preempted by federal law but upheld the most controversial provision. In Arizona v. United States [SCOTUSblog backgrounder], four specific provisions of the law were at issue: Section 2(B), which requires police officers to check the immigration status of anyone whom they arrest and allows police to stop and arrest anyone whom they believe to be an illegal immigrant; Section 3, which makes it a crime for someone even to be in the state without valid immigration papers; Section 5(C), which makes it a crime to apply for or hold a job in Arizona without proper papers; and Section 6, which gives a police officer the power to arrest an individual, without a warrant, whom the officer believes has committed a crime that could cause him or her to be deported, no matter where the crime may have occurred. In his opinion, Justice Anthony Kennedy found that sections 3, 5(C) and 6 intruded in areas reserved for the federal government:

The National Government has significant power to regulate immigration. With power comes responsibility, and the sound exercise of national power over immigration depends on the Nation’s meeting its responsibility to base its laws on a political will informed by searching, thoughtful, rational civic discourse. Arizona may have understandable frustrations with the problems caused by illegal immigration while that process continues, but the State may not pursue policies that undermine federal law.

In upholding section 2(B), the court found that 2(B) can be construed as a constitutional exercise of state authority, and that “it would be inappropriate to assume 2(B) will be construed in a way that creates a conflict with federal law.” The court noted, however, that this decision does not bar other actions against 2(B) and other parts of the law based on different constitutional issues. Kennedy was joined in his opinion by Chief Justice John Roberts and Justices Ruth Bader Ginsburg, Stephen Breyer, and Sonia Sotomayor.

Justices Antonin Scalia, Clarence Thomas, and Samuel Alito each entered dissenting opinions. In his dissent, Scalia said he would uphold the Arizona law in its entirety. He maintained that the Constitution has given states the authority to regulate immigration just as they have the authority to prosecute individuals for other crimes. He concluded that the Arizona laws do not interfere with federal regulations:

What this case comes down to, then, is whether the Arizona law conflicts with federal immigration law—whether it excludes those whom federal law would admit, or admits those whom federal law would exclude. It does not purport to do so. It applies only to aliens who neither possess a privilege to be present under federal law nor have been removed pursuant to the Federal Government’s inherent authority.

Justice Elena Kagan took no part in the decision of this case. The US Court of Appeals for the Ninth Circuit upheld an injunction blocking the four controversial sections last April before the law ever took effect, and Arizona asked the high court to weigh in [JURIST reports]. The court agreed to hear [JURIST report] the case in December.