The U.S. Department of Justice sued Florida on Tuesday to stop it from trying to remove noncitizens from its voter registration rolls.
The department says the way the state is going about doing this violates federal law. Florida says it's partly the federal government's fault for not sharing citizenship data with the state.
It's all part of the escalating battle between the Obama administration and Republican-led states over voting laws.
Earlier this year, Florida compared its voter registration lists against state driver's license records to see if there were any noncitizens illegally registered to vote. Officials say they found about 180,000 suspicious names. Local election officials sent letters to an initial list of about 2,600, asking them to verify their citizenship or be removed from the rolls.
But it quickly became clear that many of the people on the list were citizens, and that the motor vehicle data were inaccurate.
(NPR's Greg Allen reported on one World War II veteran, born in Brooklyn, N.Y., and living in Florida's Broward County, who says he was "flabbergasted" to get one of those letters.)
In its suit, the Department of Justice says what Florida is doing violates the National Voter Registration Act — also known as the motor voter law. That law prohibits the removal of voters from the rolls within 90 days of an election. Florida is holding a primary Aug. 14.
But this wasn't the first lawsuit. On Monday, Florida filed a suit of its own, accusing the federal government of violating the law by not sharing a citizenship database with the state to use in the registration roll cleanup. State officials say they've been asking the Department of Homeland Security since last year to share the database, but have had no luck.
Federal officials say they have told Florida repeatedly that the DHS database isn't set up to be compared against voter records. And that it can't be used unless the state provides more information about specific voters, such as their alien registration numbers, which the state has not done.
That aside, Florida has defended its efforts to clean up the registration rolls. Republican Gov. Rick Scott says the state has an obligation to make sure that ineligible voters don't cast ballots. State officials say they've already removed about 100 noncitizens from the rolls and that they have evidence about half of them voted in the past.
Rick Hasen, a professor at the University of California, Irvine's School of Law, says illegal voting by noncitizens does occur, but it's not widespread. He says it's often the result of confusion by noncitizens who think they're allowed to vote.
Around the country, Republicans have generally pushed for more restrictive voting laws over the past two years, saying that they're needed to protect legitimate voters and prevent fraud.
But Democrats say the restrictions are a thinly veiled effort to intimidate voters, such as minorities, who are likely to vote Democratic. A suit filed last week by the American Civil Liberties Union in Florida says that the latest purge effort disproportionately targets Hispanics.
For now, the Florida purge is in something of a limbo. Local election officials have refused to continue sending out letters to voters, because of all the questions raised.