Damian Dovarganes / AP

Members of the Coalition for Humane Immigrant Rights of Los Angeles hold a rally in response to the ruling by the U.S. Supreme Court on Arizona's immigration law, outside the Los Angeles Federal Court building on Monday.

The “show me your papers” provision of Arizona’s immigration law that was left standing by the U.S. Supreme Court is likely to wind up in a familiar place – back in the courtroom.

The nation’s top justices on Monday struck down three sections of SB 1070 but unanimously upheld the most-discussed provision: Section 2(B) requires police to check the immigration status of people they stop, detain or arrest for other legitimate reasons “if there’s reasonable suspicion” the person is in the country illegally.

But exactly how local police will go about enforcing that provision is raising more questions than answers. Enforcement had been put on hold pending the Supreme Court decision; lower courts must lift the injunction before it can take effect.

Even the Supreme Court justices hinted that they expect the provision to be legally challenged again.

“There is a basic uncertainty about what the law means and how it will be enforced. At this stage, without the benefit of a definitive interpretation from the state courts, it would be inappropriate to assume 2(B) will be construed in a way that creates a conflict with federal law,” the high court said.

“This opinion does not foreclose other preemption and constitutional challenges to the law as interpreted and applied after it goes into effect.”

The American Civil Liberties Union says it is exploring legal challenges to keep “show me your papers” from ever taking effect.

“The Supreme Court vacated the injunction against it but took pains to point out the potential constitutional problems that are inherent in Section 2(B) and drew a firm line in the sand that the state cannot cross,” said Cecillia Wang, director of the ACLU Immigrants' Rights Project. “We are going to be in court bringing new claims and evidence to stop 2(B) again.”

Among the possible claims are that the provision violates the Fourth Amendment right against unreasonable searches and seizures and that it invites racial profiling, ACLU officials say.

Joe Rubio, lead organizer for the Arizona Interfaith Network, a coalition of religious groups that opposed SB 1070, said the provision “leaves a nebulous area” if it goes into effect.

“It’s going to be important that the state monitors very closely how police deal with immigrants during regular stops and make sure racial profiling does not occur,” Rubio said.

“I think we’re going to have a few months here where people are suspending judgment to see how it’s going to be implemented.”

Jim Gilchrist, founder and president of the Minuteman Project, an anti-illegal immigration group that recruits volunteers to patrol the U.S. border with Mexico, said the Supreme Court decision “left vague” the fate of enforcement of immigration laws by local police.

“Police will be able to ask (about immigration status); however, that’s all they can do,” he said.

“Nobody’s really getting serious about this. Everybody keeps kicking the ball around the court.”

The interpretation of Section 2(B) also could put law officers in a precarious bind. There are no written instructions on how long local police must wait for federal immigration officials to respond, for example, when they encounter someone they suspect is illegal.  And immigration checks could open police up to accusations of racial profiling.

"Talk about 'no win' - if they find the person is not in authorized status, what do they do? Hold them for ICE which doesn't want them? Charge them with some state crime?" said Margaret Stock, an immigration attorney who has has testified before Congress on immigration, homeland security and military issues.

"If they make a mistake, they get sued. If they make too many mistakes, the rest of the statute gets enjoined as unconstitutional as enforced."

"We're going to get sued if we do. We're going to get sued if we don't. That's a terrible position to put law enforcement officers in," Pima County Sheriff Clarence Dupnik, whose territory covers much of southern Arizona, told The Associated Press.

Tucson police Chief Roberto Villasenor told the AP he estimates the statute will result in 50,000 additional calls a year to federal immigration authorities in his city alone.

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Suspects for minor crimes like shoplifting or vandalism, who would normally be released with a citation, must be booked into custody if immigration authorities "don't answer the phone, they never call us back after we talk to them or whatever," Villasenor said.

The Department of Homeland Security acknowledges that the provision raises the possibility that its offices might be flooded by calls for verification checks.

“The Court’s decision not to strike down Section 2 at this time will make DHS’ work more challenging,” DHS Secretary Janet Napolitano said in a statement.

Jon Feere, of the Center for Immigration Studies, a Washington-based think tank that advocates for limited legal immigration, suggested that enforcement will ultimately lead to tougher immigration laws once Congress or the courts are forced to act definitively.

“There will now be an extensive record every time Arizona contacts ICE (Immigration and Customs Enforcement) about an illegal alien detained by local law enforcement. When the White House inevitably refuses to take an illegal alien into custody, forcing Arizona to release the alien back out onto the streets, it will become a national story if the alien goes on to commit a serious crime. Lax federal enforcement of immigration laws will be to blame,” he wrote in a blog post.

Five other states have passed laws similar to Arizona’s -- Alabama, Georgia, Indiana, South Carolina and Utah.

The ACLU says it has raised nearly $8.8 million in a special fund to challenge “show me your papers” laws in Arizona and those other states. And it’s ready to go to court again.

“If state governments enact new immigration bills, we say bring it on, we will see them in court,” ACLU Executive Director Anthony Romero said Monday.

The Justice Department has set up a federal hotline for the public to report potential civil rights concerns regarding the Arizona law. The phone number is 1-855-353-1010. The email is: SB1070(at)usdoj.gov.

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The U.S. Supreme Court ruling that struck down much of Arizona’s strict anti-illegal immigration law but upheld one of its most controversial provisions has some illegal aliens on edge. But will it prompt them to pack their bags and leave the state anytime soon?

Some may leave but more likely than not most will stay put, say immigration-rights activists and illegal immigrants contacted by msnbc.com.

“The main thing we’re focusing on is advocating for families not to flee Arizona, to stay here and help fight for their rights to be here,” said Opal Tometi, a member of the board of the Puente Movement, an Arizona-based immigrant rights group, and national organizer for the Black Alliance for Just Immigration. 

Leticia Ramirez, a mother of three who lives in the Phoenix area and says she is undocumented, said the mixed Supreme Court ruling could make day-to-day life harder for her family but they plan to stay anyway.

Ross D. Franklin / AP

Members of Promise Arizona, from left, Leonila Martinez, Patricia Rosas and Gustavo Cruz, react to the U.S. Supreme Court decision on Arizona's controversial immigration law in Phoenix on Monday.

“If we fight together it’s going to be better for us than just one person fighting  for all the community,” she said.

The Supreme Court struck down key provisions of Arizona’s SB 1070 but said the state could go forward with a much-debated portion requiring police to check the immigration status of anyone they stop, detain or arrest for other reasons if they have “reasonable suspicion” that the person is in the country illegally. Even there, though, the justices said the "show me your papers” provision could be subject to additional legal challenges and advised states not to apply the law in such a sweeping way that it would become unconstitutional. They also said officers can't arrest people on minor immigration charges.

Gov. Brewer: 'Heart' of immigration law proven constitutional

Tometi said the provision requiring police to try to determine the immigration status of a person stopped for other reasons might deter some undocumented immigrants from coming to Arizona. But she says it’s unlikely to lead to full-scale departures from the state, especially for families that have been in Arizona illegally for years -- and even decades.

”I think that people will stay,” she said.

“What we’ve decided as a community in Arizona is that we’re going to do community organizing and defend our families, whether they’re documented or undocumented,” Tometi said. 

Both sides declare victory in court's immigration ruling

She said activists are establishing “barrio defense committees“-- volunteer neighborhood committees that provide a network of support services for people who might be swept up in detention or deportation proceedings.

Ramirez, who said she has been in the U.S. for 18 years, said the ruling will make routine day-to-day activities “difficult” for her family.

“We’re not going to be living a normal life anymore. We’ll be afraid when we get stopped,” she said.

“We’re not going to be able to take my kids to soccer practice, to soccer games, to movies, to the mall because I’m afraid we're going to be stopped. I don’t want to put my kids in that situation. A lot of people won’t even want to take their kids to school because they’re afraid of being stopped.”

She said while some illegal immigrants might leave, she’s determined to stay.

“Leaving Arizona leaving is not going to resolve anything,” Ramirez said. “I would say to my community: Stay so we can fight together. People want to raise their kids and have a family. They’re going to risk it.”

Read the Supreme Court decision on SB 1070

Fernando Lopez, 21, says he experienced the provision firsthand -- being arrested after an Arizona Highway patrolman asked for his papers. The Mexican national living in Phoenix is fighting deportation and says even if he hadn't been caught he'd still fight to stay in the U.S.

"My brother left two years ago when the law was passed," he told msnbc.com, but "running is not the solution."

"The least we can do is organize as a community," said Lopez, who does acknowledge it's easier for him to stay since he's not married and has no children. 

The Arizona DREAM Act Coalition, an organization of immigrant youth and their supporters, said the section that was upheld is "conducive to racially profiling citizens, legal residents and undocumented immigrants."

"We will continue to educate our community on how we can overcome the implementation of this section so the impact to the people in our state is minimized," the group said in a statement.

"We encourage the community to stand firm, to not panic, and to stay informed."

Natalie Cruz, 24, also plans to stay and hopes the DREAM Act will give her some protection while she studies in Phoenix. Among her family, one aunt said she'd return to Mexico if the court upheld the police provision, Cruz said, but others plan to stay.

That's not to say life will be the same. "It is going to change how I do things -- like driving," Cruz said.

Jim Gilchrist, founder and president of the Minuteman Project, a California-based group that advocates tough enforcement of immigration laws, says the Supreme Court opinion is unlikely to have a dramatic impact on illegal immigrants in Arizona.

While local police can inquire about the legal status of someone they stop for probable cause for something else, “that’s apparently all they can do,” Gilchrist said.

“It doesn’t put any serious teeth into enforcing immigration laws,” he said.

The U.S. Department of Homeland Security says even though the agency expects a lot more calls from Arizona police to check people's immigration status, deportations won't necessarily increase because federal officials are only targeting those who have been convicted of a felony or present a securty threat.

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David Goldman / AP file

Demonstrators march in lower Manhattan to protest Arizona's controversial immigration law during a rally in New York on May 1, 2010.

A U.S. Supreme Court decision on the fate of Arizona’s strict anti-illegal immigration law will have implications far beyond the Grand Canyon state’s borders. But who ultimately wins and loses will be up for debate even after the justices rule by this summer.

The high court on Wednesday will hear oral arguments on SB 1070, a bill signed by Gov. Jan Brewer in April 2010 to help authorities drive illegal immigrants out of Arizona. Implementation of the most controversial sections  -- including a requirement that local police check the immigration status of a criminal suspect if they have “reasonable suspicion” that person is in the country illegally -- has been put on hold by lower courts pending action by the Supreme Court.

The Obama administration is arguing the law should be struck down because immigration policy is rightfully set by the federal government, not states. Arizona, the border of choice for illegal entries from Mexico, contends immigration isn’t exclusively a federal matter and the state has the right to act because federal authorities haven’t done their job.

The fate of similar immigration laws in states like Alabama and Georgia will also likely hinge on the high court’s decision. Meanwhile, states like New York and California fear that illegal immigrants will flee from Arizona to their locales if the law is upheld.

“Depending on how the court rules, our nation could be changed in major ways, because the decision may shift power dramatically between the states and the federal government,” says Margaret Stock, an immigration lawyer and University of Alaska Anchorage adjunct professor who has written numerous articles and testified before Congress on immigration law issues.

“The Supremes' decision will have a significant bearing on other states' actions -- whichever parts of SB 1070 are upheld are likely to be replicated in a number of other states,” adds Mark Krikorian, executive director of the Center for Immigration Studies,  a Washington-based research organization that supports tougher immigration policies.

Saul Loeb / AFP - Getty Images file

Arizona Gov. Jan Brewer is a staunch defendant of SB 1070.

If the major components of the law are struck down, it would be a serious rebuke to Arizona and Brewer, who says California and the 10 other states supporting the Obama administration’s argument are misguided in their criticism.

“States joining California in opposing Arizona in this fight may think they have little at stake. They are buffered from the troubles along our nation’s southern border by geography or, in the case of Hawaii, an entire ocean,” Brewer said in a statement on March 29. “But this debate is not just about illegal immigration. It is about every state’s authority and obligation to act in the best interest and welfare of its citizens.”

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Brewer’s reputation – and perhaps even her political future -- are at stake if the law is struck down.

“I think that a governor’s job is to make the lives of people who live in the state better. Certainly either Jan Brewer is going to look like a fool … or she’s going to fail in her job of governing Arizona well,” says Ian Millhiser, senior constitutional policy analyst with the left-leaning Center for American Progress.

Stock says even if the justices uphold Arizona's law, Arizona could still turn out to be the loser. 

“The law that Arizona passed is very expensive to implement, and is likely to cause businesses and younger families to leave Arizona for other states like California. Arizona could lose a lot of business and thousands of people might leave the state, or decide not to settle there in the first place.  So even if Arizona ‘wins,’ the victory may be a Pyrrhic one,” she told msnbc.com by email.

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Tom Fitton, president of Judicial Watch, a conservative government watchdog group, doesn’t buy that argument. He says crime in Arizona has dropped significantly since passage of SB 1070 and predicts there will be “a rush of other states” to follow Arizona’s example if the law is upheld.

"Arizona won’t complain if illegal aliens leave, that’s for sure," he said. “If upheld, Arizona won’t be an outlier."

State Sen. Russell Pearce, author of the bill, says Phoenix has experienced a 30-year low crime rate since SB 1070's passage. "To ignore the positive impact of SB 1070 in the city of Phoenix is to ignore the huge elephant in the middle of the room," he wrote in a court brief.

Some Arizona hotel managers say the tourism industry took a hit due to the recession and the controversy over the immigration law, as some groups announced boycotts of the state. The lodging industry now appears to be rebounding slowly, with mixed numbers for January and February but an overall strong March, hotel managers said at a recent convention.

Robert Hayward of Warnick & Co., who led the convention, said Arizona's image has improved in the minds of travelers, and he hopes the upcoming Supreme Court hearing won't reverse that.

"The concern is how the Supreme Court opens that issue back up and how that will impact the impression [of Arizona] on a national level going forward," Hayward told the crowd, KTVK reported.

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Gabriel “Jack” Chin, an immigration law expert who spoke out vigorously against SB 1070 while he was a professor at the University of Arizona, says it’ll hard to predict who will emerge a winner or loser even after the high court rules.

“One might assume that Mexican families would come out ahead if the law is struck down, because the states would not be able to pass laws designed to drive them out.  But in the past, when state immigration laws have been struck down by the Supreme Court, there sometimes has been a legal backlash. For example, when California's laws designed to keep out Chinese immigrants were held unconstitutional in 1876, Congress responded by passing the Chinese Exclusion Act," says Chin, who is now with UC Davis.

“If the United States wins the case, it may be a disaster for Mexican families because it could lead Congress to embrace even more rigorous enforcement methods. The same underlying political dynamic means that if Arizona loses, it could hurt the Republicans because it shows they went too far, or it could help them because it shows that the only way this issue can be resolved is by electing a Republican Congress,” Chin adds.

Fitton, of Judicial Watch, says the ruling could be a double-edged sword not for Arizona, but for Obama.

“If he loses here it feeds the narrative that his agencies are out of control with these lawsuits attacking states and politicizing immigration,” Fitton says. And if justices rule against the federal government, he says, “I think it will motivate his opponents.”

Evelyn Haydee Cruz, a law professor who directs the Immigration Law & Policy Clinic at Arizona State University, predicts a mixed Supreme Court ruling in which there are no clear-cut winners and losers.

“The constitutional question is so complex that most likely both sides will be unhappy with some parts and happy with others. Each of the players will try to grab onto whatever language in the decision makes them look better,” Cruz says. “The Arizona governor will look for language validating state enforcement of immigration laws and state independence.  The Obama administration will look for language that preserves federal supremacy over immigration policy.”

A decision in Arizona v. United States is expected in June or July. You can read a preview of the arguments in the case here.

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