Opponents of Arizona's law see it as an attack on vulnerable voter groups such as minorities, immigrants and the elderly. They say they've counted more than 31,000 potentially legal voters in Arizona who easily could have registered before Proposition 200 but were blocked initially by the law in the 20 months after it passed in 2004. They say about 20 percent of those thwarted were Latino.
But Arizona officials say they should be able to pass laws to stop illegal immigrants and other noncitizens from getting on their voting rolls. The Arizona voting law was part of a package that also denied some government benefits to illegal immigrants and required Arizonans to show identification before voting.
"It is the burden of the states to determine the eligibility of the voters," Horne said.
In Colorado, election officials found 441 noncitizens on the voter rolls out of nearly 3.5 million voters. Florida officials found 207, or 0.001 percent of the state's 11.4 million registered voters. In North Carolina, 79 people admitted to election officials that they weren't citizens and were removed from the rolls, along with 331 others who didn't respond to repeated inquires.
Horne compared the Arizona system to an airline sending out e-tickets instead of paper tickets but asking for identification before allowing passengers to board the airplane. "That would not contradict the statement that they are accepting and using e-tickets," he said.
But Justice Elena Kagan didn't accept that analogy, saying Arizona went further. "Wouldn't it contradict it if instead of saying 'Well, we'd like you to offer identification,' saying, 'Well, we'd like you also to have a paper ticket'?" she said.
Arizona asked the federal government to add its citizenship eligibility requirements as a state add-on to the federal form but was turned away. Scalia said they should have sued to overturn that decision. "Why didn't you do that?" said Scalia, who indicated that he would look on that challenge favorably.
The decision not to challenge was his predecessor's, Horne said.
This is the second voting issue the high court is tackling this session. Last month, several justices voiced deep skepticism about whether a section of the Voting Rights Act of 1965, a law that has helped millions of minorities exercise their right to vote, especially in areas of the Deep South, was still needed.
The court will make a decision later this year.
The case is 12-71, Arizona v. Inter Tribal Council of Arizona, Inc.
Billeaud reported from Phoenix.
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