Arizona Efforts to Stem Illegal Immigration Largely Preempted by Federal Regulations

Arizona suffered a blow in its effort to cut off the flow of illegal aliens surging over its border with Mexico when the U.S. Supreme Court June 25 ruled 5–3 that three portions of the law the state adopted to address the problem are preempted by federal law (Arizona v. United States, U.S., No. 11-182).

At the same time, however, the majority, in an opinion by Justice Anthony M. Kennedy, said that a provision of the law that requires state officers to determine the immigration status of a lawfully stopped individual is not preempted.

A key takeaway, one ...