Justices Antonin Scalia and Clarence Thomas each filed separate dissents arguing that SB 1070 should be upheld in its entirety.

WSJ: Supreme Court Splits on Arizona Immigration Law

Federal courts have blocked four key parts of the state's Support Our Law Enforcement and Safe Neighborhoods Act, known as SB 1070.

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Arizona had just passed SB 1070 requiring police to question people about their immigration status and Utah seemed destined to follow the same course.

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Two and a half years after LAWA was passed, Arizona created a more controversial law called SB 1070 to enforce immigration laws outside of the workplace.

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Dupnik said he opposed SB 1070 because if the entire law had been upheld by the federal courts, it would have resulted in overcrowded jails and overburdened state courts.

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Justice Samuel Alito agreed with the majority that Arizona's alien-registration requirement was void, but voted to uphold SB 1070 provisions making it a crime for illegal immigrants to seek work and authorizing warrantless arrests of certain aliens.

WSJ: Supreme Court Splits on Arizona Immigration Law

Sporting a white baseball cap that that reads, "100% American Citizen, " Schwartz says she believes that SB 1070 came about because law enforcement in Phoenix was fed up over not being able to ask suspects about their immigration status.

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Supporters say they changed SB 1070.

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While a federal judge in 2010 stopped enforcement of the most controversial provisions, other parts of SB 1070 were given the go-ahead, including a ban on "sanctuary cities, " or municipalities with laws or policies that render them relatively safe for undocumented immigrants.

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