WASHINGTON — The Obama administration Friday urged the Supreme Court to review and set aside an Arizona law that sanctions employers who hire illegal immigrants, saying it would disrupt the “careful balance” that Congress struck in federal immigration law.
The act in question is not the new Arizona law that President Barack Obama and other members of his administration have criticized. That law requires police — after making “lawful contact,” defined as a lawful stop, detention or arrest — to question anyone who appears to be in the country illegally.
The hiring law, the Legal Arizona Workers Act, imposes tougher sanctions than federal law for hiring illegal workers. If the court chooses to hear the case, its ruling could show how receptive the justices would be to arguments that enforcing immigration laws is a federal responsibility that cannot be usurped by the states.
The Arizona act is being challenged by a coalition of organizations that include the U.S. Chamber of Commerce, Latino groups and civil libertarians. Business groups want to head off conflicting state laws on employer sanctions, while others worry the penalties, which include the loss of business licenses, would discourage companies from hiring even those legally in the U.S.
The administration, in a brief submitted by Acting Solicitor General Neal Katyal, said federal law should pre-empt state efforts.
The Arizona law would “disrupt a careful balance that Congress struck nearly 25 years ago between two interests of the highest importance: ensuring that employers do not undermine enforcement of immigration laws by hiring unauthorized workers, while also ensuring that employers not discriminate against racial and ethnic minorities legally in the country,” Katyal wrote.
The court asked the government in November for its view. The response might have been delayed by two factors. Homeland Security Secretary Janet Napolitano is the state’s former governor and was the first defendant when the challenge was filed. And Obama selected Solicitor General Elena Kagan this month as his choice to replace retiring Justice John Paul Stevens.



