By MARK SHERMAN, ASSOCIATED PRESS

WASHINGTON — The Supreme Court struck down key provisions of Arizona's crackdown on immigrants Monday but said a much-debated portion on checking suspects' status could go forward.

The court did not throw out the state provision requiring police to check the immigration status of someone they suspect is in the United States without documentation. Even there, though, the justices said the provision could be subject to additional legal challenges.

The decision upholds the "show me your papers" requirement for the moment. But it takes the teeth out of it by prohibiting police officers from arresting people on minor immigration charges.

The court announced that Thursday would be the last day of rulings this term, which means the decision on President Barack Obama's landmark health care overhaul probably will come that day.

Justice Anthony Kennedy wrote the opinion for the court that was unanimous on allowing the status check to go forward. The court was divided on striking down the other portions.

Kennedy said the law could – and suggested it should – be read to avoid concerns that immigration status checks could lead to prolonged detention.

The court struck down these three major provisions: requiring all immigrants to obtain or carry immigration registration papers, making it a state criminal offense for an undocumented immigrant to seek work or hold a job and allowing police to arrest suspected undocumented immigrants without warrants.

The Obama administration sued to block the Arizona law soon after its enactment two years ago. Federal courts had refused to let the four key provisions take effect.

Five states – Alabama, Georgia, Indiana, South Carolina and Utah – have adopted variations on Arizona's law. Parts of those laws also are on hold pending the outcome of the Supreme Court case.

Chief Justice John Roberts and Justices Stephen Breyer, Ruth Bader Ginsburg and Sonia Sotomayor joined all of Kennedy's opinion.

Justices Antonin Scalia and Clarence Thomas would have allowed all the challenged provisions to take effect. Justice Samuel Alito would have allowed police to arrest undocumented immigrants who seek work, and also make arrests without warrants.

Scalia, in comments from the bench, caustically described Obama's recently announced plans to ease deportation rules for some children of undocumented immigrants.

"The president said at a news conference that the new program is `the right thing to do' in light of Congress' failure to pass the administration's proposed revision of the Immigration Act. Perhaps it is, though Arizona may not think so. But to say, as the court does, that Arizona contradicts federal law by enforcing applications of the Immigration Act that the president declines to enforce boggles the mind," Scalia said.

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  • The Template: California Proposition 187 (1994)

    California's Proposition 187 was submitted to the voters with the full support of then Republican governor Pete Wilson. It essentially blamed undocumented immigrants for the poor performance of the state economy in the early 1990s. The law called for cutting off benefits to undocumented immigrants: prohibiting their access to health care, public education, and other social services in California. It also required state authorities to report anyone who they suspected was undocumented. <strong>Status:</strong> The law passed with the support of 55 percent of the voters in 1994 but declared unconstitutional 1997. The law was killed in 1999 when a new governor, Democrat Gray Davis, refused to appeal a judicial decision that struck down most of the law. Even though short-lived, the legislation paved the way for harsher immigration laws to come. On the other hand, the strong reaction from the Hispanic community and immigration advocates propelled a drive for naturalization of legal residents and created as many as one million new voters.

  • The Worst: Arizona SB 1070

    The Arizona Act made it a misdemeanor for an undocumented immigrant to be within the state lines of Arizona without legal documents allowing their presence in the U.S. This law has been widely criticized as xenophobic and for encouraging racial profiling. It requires state authorities to inquire about an individual's immigration status during an arrest when there is "reasonable suspicion" that the individual is undocumented. The law would allow police to detain anyone who they believe was in the country illegally. <strong>Status:</strong> The law was signed into law by Arizona Governor Jan Brewer on April 23, 2010. But it has generated a swirl of controversy and questions about its constitutionality. A federal judge issued a ruling that blocked what critics saw as some of the law's harshest provisions. House: 35-31 (4/12/2011)

  • Following Arizona's Footsteps: Georgia HB 87

    The controversy over Arizona's immigration law was followed by heated debate over Georgia's own law. HB 87 required government agencies and private companies to check the immigration status of applicants. This law also limited some government benefits to people who could prove their legal status. <strong>Status:</strong> Although a federal judge temporarily blocked parts of the law considered too extreme, it went into effect on July 1st. 2011. House: 113-56 Senate: 39-17

  • Verifying Authorized Workers: Pennsylvania HB 1502

    This bill, which was approved in 2010, bans contractors and subcontractors employ undocumented workers from having state construction contracts. The bill also protects employees who report construction sites that hire illegal workers. To ensure that contractors hire legal workers, the law requires employers to use the identification verification system E-verify, based on a compilation of legally issued Social Security numbers. <strong>Status:</strong> Approved on June 8th 2010. House: 188-6 (07/08/2010) <a href="http://www.flickr.com/photos/donkeyhotey/" target="_hplink">Flickr photo by DonkeyHotey</a>

  • A Spin Off of Arizona: Utah HB 497

    Many states tried to emulate Arizona's SB 1070 law. However, most state legislatures voted against the proposals. Utah's legislature managed to approve an immigration law based on a different argument. Taking into consideration the criticism of racial profiling in Arizona, Utah required ID cards for "guest workers" and their families. In order to get such a card workers must pay a fee and have clean records. The fees go up to $2,500 for immigrants who entered the country illegally and $1,000 for immigrants who entered the country legally but were not complying with federal immigration law, <a href="http://articles.latimes.com/2011/mar/06/nation/la-na-illegal-immigration-20110306" target="_hplink">according to the LA Times.</a> <strong>Status: </strong> Law went into effect on 03/15/2011 House: 59-15 (03/04/2011) Senate: 22-5 (03/04/2011)

  • The Most Comprehensive: Florida HB-1C

    Florida's immigration law prohibits any restrictions on the enforcement of federal immigration law. It makes it unlawful for undocumented immigrants within the state to apply for work or work as an independent contractor. It forbids employers from hiring immigrants if they are aware of their illegal status and requires work applicants to go through the E-verify system in order to check their Social Security number. <strong>Status: </strong>effective since October 1st, 2010

  • The Hot Seat: Alabama HB 56

    The new immigration law in Alabama is considered the toughest in the land, even harder than Arizona's SB 1070. It prohibits law enforcement officers from releasing an arrested person before his or her immigration status is determined. It does not allow undocumented immigrants to receive any state benefit, and prohibits them from enrolling in public colleges, applying for work or soliciting work in a public space. The law also prohibits landlords from renting property to undocumented immigrants, and employers from hiring them. It requires residents to prove they are citizens before they become eligible to vote. The law asked every school in the state to submit an annual report with the number of presumed undocumented students, but this part, along with others, were suspended by federal courts. <strong>Status:</strong> Approved June 2nd, 2011 House: 73-28 (04/05/2011) Senate: 23-11 (05/05/2011) <a href="http://www.flickr.com/photos/longislandwins/" target="_hplink">Flickr photo by longislandwins</a>