by Acting Solicitor General Neal Katyal

by Acting Solicitor General Neal Katyal The act in question is not the strict new Arizona law Tarpsthat President Obama and other members of his administration have criticized. That measure requires police to question anyone who appears to be in the country illegally.

The law being challenged, 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, Hispanic groups and civil libertarians. Business groups want to head off a proliferation of conflicting state laws on employer sanctions, while others worry that the penalties, which include the loss of business licenses, would discourage companies from hiring even those legally in the country.

The Obama administration, in a brief submitted by Acting Solicitor General Neal Katyal, said federal law should preempt 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 of the case. 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 earlier this month as his choice to replace retiring Justice John Paul Stevens.

Separately, Justice Department officials met Friday in Phoenix with Arizona Attorney General Terry Goddard and aides to Gov. Jan Brewer (R) to express strong reservations about the new law, which Tarpsgoes into effect July 29. The administration fears the law could lead to widespread racial profiling.