ATLANTA (AP) - A federal appeals court pressed Georgia attorneys Thursday on whether the state's new law targeting illegal immigration conflicts with federal rules and challenged critics of the crackdown to explain why local authorities can't use the new powers to complement federal efforts.

The three-judge panel of the 11th U.S. Circuit Court of Appeals peppered both sides with questions at a hearing on a lawsuit opposing Georgia's new law filed by activist groups. The judges were set to hear arguments later on two separate challenges to Alabama's immigration law filed by immigrant rights groups and the Justice Department.

The panel said it wouldn't rule until the U.S. Supreme Court releases a decision on a federal government challenge to a similar law passed by Arizona. The arguments in that case, set for April, revolve around a sweeping law taking aim at illegal immigration passed in 2010 that was opposed by activist groups and the federal government.

At Thursday's hearing, Circuit Judges Bev Martin and Charles Wilson repeatedly asked state attorney Devon Orland whether the state law pre-empts federal rules. Martin said she's concerned that part of the law "bumps up against this very comprehensive federal scheme."


Orland urged the panel to view the state law as a supplement to federal statutes that allow "dual enforcement," much like laws that allow both state and federal prosecutors to charge suspects with drug crimes.

"It's axiomatic that both the state and the federal government can both prosecute the same crime," she argued, adding that the law's intent is not to "persecute people."

Opponents of the measure argued that immigration is a federal issue that shouldn't be governed by a patchwork of state laws. Omar Jadwat of the American Civil Liberties Union said the law forces "police officers to take off their police officer's hat and put on an immigration enforcement hat."

That prompted Wilson to ask him whether a state can seek to regulate illegal immigration if it decides the "illegal alien population morphs into a public safety concern." Jadwat countered that it should be up to federal officials to address the issue.

The three-judge panel also included U.S. District Judge Richard Voorhees, a visiting judge from North Carolina who asked few questions during the hearing. Wilson and Martin were appointed by Democratic presidents while Voorhees was tapped by Republican Ronald Reagan.

Five other states - Alabama, Georgia, Indiana, South Carolina and Utah - adopted variations on Arizona's law last year, with Alabama's widely considered the toughest in the nation. All five laws have been challenged by coalitions of civil rights and immigrant rights groups, and the federal government has sued to block those in Alabama, South Carolina and Utah.

Opponents of the measures argue such laws lead to discrimination and racial profiling and that immigration is a federal issue that shouldn't be governed by a patchwork of state laws. Supporters say states have been forced to act to protect their resources because the federal government hasn't done enough to quell the influx of illegal immigrants.

A federal judge in June temporarily blocked parts of Georgia's law pending the outcome of the legal challenge filed by the activist groups. One blocked section would authorize police to check the immigration status of suspects who don't have proper identification. The other would create a state penalty for people who knowingly and willingly transport or harbor illegal immigrants while committing another crime.

Georgia appealed that decision to the 11th Circuit, which means the court will decide whether the injunction can remain in place.

After a federal judge in Alabama declined in September to block many provisions of that state's law, the 11th Circuit in October temporarily blocked some parts, including a requirement for schools to check students' immigration status. But the appeals court left intact a section that allows police to check a person's immigration status during a traffic stop and to detain someone they believe is in the country illegally. Courts also can't enforce contracts involving illegal immigrants, such as leases, and it's a felony for an illegal immigrant to do business with the state for basic things such as getting a driver's license.

The 11th Circuit will now decide whether to block sections of the law that had been allowed to go into effect, and whether to leave the injunctions previously obtained on other sections in place.

The arguments attracted national media and dozens of protesters, who rallied outside the downtown Atlanta courtroom chanting slogans and holding signs saying: "We are families not fugitives" and "Hate Hurts Alabama."