PHOENIX — Arizona is preparing to ask an appeals court to lift a judge’s ruling that put most of the state’s immigration law on hold in a key first-round victory for the federal government in a fight that may go to the U.S. Supreme Court.

Three people were arrested Thursday morning at the federal courthouse in Phoenix, where police had riot gear ready in case the protest got out of hand. It was not immediately clear why the people were detained.

Hundreds of protesters marched from the state Capitol at dawn, then held a prayer service at a local church before gathering in front of the federal courthouse.

Opponents also planned a sit-in at the office of Sheriff Joe Arpaio. The sheriff said if protesters were disruptive they’d be arrested, and he vowed to go ahead with a crime sweep targeting illegal immigrants.

“My deputies will arrest them and put them in pink underwear,” Arpaio said, referring to one of his odd methods of punishment for prisoners. “Count on it.”

Gov. Jan Brewer called Wednesday’s decision by U.S. District Judge Susan Bolton “a bump in the road” and vowed to appeal.

Paul Senseman, a spokesman for Brewer, said Arizona would ask the 9th U.S. Circuit Court of Appeals in San Francisco later Thursday to lift Bolton’s preliminary injunction and to expedite its consideration of the state’s appeal.

Bolton indicated the government has a good chance at succeeding in its argument that federal immigration law trumps state law. But the key sponsor of Arizona’s law, Republican Rep. Russell Pearce, said the judge was wrong and predicted the state would ultimately win the case.

Opponents of the law said the ruling sends a strong message to other states hoping to replicate the law.

“Surely it’s going to make states pause and consider how they’re drafting legislation and how it fits in a constitutional framework,” Dennis Burke, the U.S. attorney for Arizona, told The Associated Press. “The proponents of this went into court saying there was no question that this was constitutional, and now you have a federal judge who’s said, ‘Hold on, there’s major issues with this bill.'”

He added: “So this idea that this is going to be a blueprint for other states is seriously in doubt. The blueprint is constitutionally flawed.”

In her temporary injunction, Bolton delayed the most contentious provisions of the law, including a section that required officers to check a person’s immigration status while enforcing other laws. She also barred enforcement of parts requiring immigrants to carry their papers and banned illegal immigrants from soliciting employment in public places – a move aimed at day laborers that congregate in large numbers in parking lots across Arizona. The judge also blocked officers from making warrantless arrests of suspected illegal immigrants.

“Requiring Arizona law enforcement officials and agencies to determine the immigration status of every person who is arrested burdens lawfully present aliens because their liberty will be restricted while their status is checked,” said Bolton, a Clinton administration appointee who was assigned the seven lawsuits filed against Arizona over the law.

Other provisions that were less contentious were allowed to take effect Thursday, including a section that bars cities in Arizona from disregarding federal immigration laws.

The 11th-hour ruling came just as police were preparing to begin enforcement of a law that has drawn international attention and revived the national immigration debate in a year when Democrats are struggling to hold on to seats in Congress.

The ruling was anxiously awaited in the U.S. and beyond. About 100 protesters in Mexico City who had gathered at the U.S. Embassy broke into applause when they learned of the ruling via a laptop computer. Mariana Rivera, a 36-year-old from Zacatecas, Mexico, who is living in Phoenix on a work permit, said she heard about the ruling on a Spanish-language news program.

“I was waiting to hear because we’re all very worried about everything that’s happening,” said Rivera, who phoned friends and family with the news. “Even those with papers, we don’t go out at night at certain times there’s so much fear (of police). You can’t just sit back and relax.”

More demonstrators opposed to the law planned to gather Thursday, with the Los Angeles-based National Day Laborer Organizing Network and the immigrant-rights group Puente saying they would march from the state Capitol.

Lawmakers or candidates in as many as 18 states say they want to push similar measures when their legislative sessions start up again in 2011. Some lawmakers pushing the legislation said they would not be daunted by the ruling and plan to push ahead in response to what they believe is a scourge that needs to be tackled.

Arizona is the nation’s epicenter of illegal immigration, with more than 400,000 undocumented residents. The state’s border with Mexico is awash with smugglers and drugs that funnel narcotics and immigrants throughout the U.S., and the influx of illegal migrants drains vast sums of money from hospitals, education and other services.

“We’re going to have to look and see,” said Idaho state Sen. Monty Pearce, a second cousin of Russell Pearce and a supporter of immigration reform in his state. “Nobody had dreamed up, two years ago, the Arizona law, and so everybody is looking for that crack where we can get something done, where we can turn the clock back a little bit and get our country back.”

Kris Kobach, the University of Missouri-Kansas City law professor who helped write the law and train Arizona police officers in immigration law, conceded the ruling weakens the force of Arizona’s efforts to crack down on illegal immigrants. He said it will likely be a year before a federal appeals court decides the case.

“It’s a temporary setback,” Kobach said. “The bottom line is that every lawyer in Judge Bolton’s court knows this is just the first pitch in a very long baseball game.”
In the meantime, other states like Utah will likely take up similar laws, possibly redesigned to get around Bolton’s objections.

“The ruling … should not be a reason for Utah to not move forward,” said Utah state Rep. Carl Wimmer, a Republican from Herriman City, who said he plans to co-sponsor a bill similar to Arizona’s next year and wasn’t surprised it was blocked. “For too long the states have cowered in the corner because of one ruling by one federal judge.”

The core of the government’s case is that federal immigration law trumps state law – an issue known as “pre-emption” in legal circles and one that dates to the founding of America. In her ruling, Bolton pointed out five portions of the law where she believed the federal government would likely succeed on its claims.

The Justice Department argued in court that the law was unconstitutional and that allowing states to push their own measures would lead to a patchwork of immigration laws across the nation and disrupt a carefully balanced approach crafted by Congress.
Arizona argues that the federal government has failed to secure the border, and that it has a right to take matters into its own hands.

For now, the federal government has the upper-hand in the dispute, by virtue of the strength of its arguments and the precedent on the pre-emption issue. The Bush administration successfully used the pre-emption argument to win consumer product cases, and judges in other jurisdictions have looked favorably on the argument in immigration disputes.

“This is clearly a significant victory for the Justice Department and a defeat for the sponsors of this law,” said Peter Spiro, a constitutional law professor at Temple University who has studied immigration law extensively. “They will not win on this round of appeals. They’ll get a shot after a trial and a final ruling by Judge Bolton.”