A judge ordered the state to purge more than 200,000 voters from the rolls. What should I do if I'm one of them?

Molly Beck | Milwaukee Journal Sentinel

MADISON - A Wisconsin judge on Friday ordered the Wisconsin Elections Commission to remove the registrations of more than 200,000 Wisconsin voters who may have moved and were sent letters saying they might need to re-register to vote.

RELATED: Protesters demand Wisconsin voter rolls be left alone, call judge's decision to remove them 'voter suppression'

The case has become a proxy for the ultimate battleground Wisconsin will play in the re-election bid of President Donald Trump, who won the state by fewer than 23,000 votes in 2016 — propelling him to victory.

Here's a look at the case and what it means for voters:

Who sued and why?

State elections officials in October sent letters to about 234,000 Wisconsin voters it believes may have moved.

Soon after, the conservative legal firm Wisconsin Institute for Law & Liberty on behalf of three men from suburban Milwaukee sued the Wisconsin Elections Commission arguing state law requires registrations of such voters be removed if the voters haven't within 30 days told the commission they didn't actually move.

State elections officials say they don't have enough reliable evidence to prove these voters have indeed moved and want to wait to sort it out until after the presidential election in 2020 to preserve access to voting.

The judge's ruling Friday came down on the side of the legal firm.

What should people do if they get a letter?

Regardless of whether they have moved, they should take action. If they haven't moved, they can tell election clerks they are still at their current address and keep their voter registrations current.

If they have moved, they need to update their voter registration.

To find out whether you're one of these voters, check your status and register, if needed, at https://myvote.wi.gov. You can take care of your registration at the polls on election day, too, but you will need to fill out paperwork and provide proof of residence, such as a driver's license, property tax bill, utility bill, bank statement, paycheck stub, lease or workplace ID.

What have the voters who got the letter been told?

The letters state that there is reason to believe the recipients may have moved. It asks them to update their registrations if they have moved or return a postcard saying they still live at the same address.

But the letters don't say the people could have their voter registrations deactivated. That could become an important part of the lawsuit because voter advocates will likely contend people deserve to be warned before they have their voter registrations invalidated.

Why does the state believe these voters may have moved?

The state generated the list of voters who have possibly moved using data from the Electronic Registration Information Center, or ERIC, which helps 29 states keep their voting rolls accurate.

ERIC gathers information from other sources, such as the U.S. Postal Service and departments of motor vehicles, to detect when someone may have moved.

Sometimes that information provides false leads. For instance, some people might register their car at a relative's house to avoid paying a local wheel tax but still maintain their same home for voting purposes.

Elections Commission chair Dean Knudson on Monday sought to codify the ERIC data as "reliable," but the panel deadlocked on the issue 3-3 and the motion failed.

Why does it matter whether voters' addresses are up to date?

Election clerks want the most accurate voting rolls possible, and identifying people who may have moved helps them keep their records up to date.

Voters have to be registered at their proper address to make sure they go to the correct voting precinct and get the correct ballot. If they vote from the wrong address, they could be voting in the wrong local, legislative and congressional races.

Who is affected?

The letters went to about 7% of the state's 3.3 million registered voters.

The largest number of letters were sent to voters in the state's two largest cities, Milwaukee and Madison, which are also the state's Democratic strongholds. About 35,000 voters in Milwaukee and about 18,000 in Madison were sent the letters.

The next largest groups of voters were in Eau Claire, Green Bay and La Crosse, communities with UW System campuses. About 4,000 voters were sent letters in each of those cities, according to the Elections Commission.

In New Berlin, a reliably Republican city, about 1,400 voters were sent letters. A similar number of letters were sent to voters in Menomonee Falls, another bastion for Republicans.

What are the political ramifications of the lawsuit?

Wisconsin is perhaps the most closely watched state in next year's presidential election. Donald Trump defeated Hillary Clinton by 22,748 votes in 2016, and both sides will be monitoring the case at a time when the state is again split politically.

Democrats fear removing a fraction of the total number of people who may have moved could matter in close races, including the presidential contest.

Where does the issue stand?

On Monday, the elections commission met to discuss the decision. Its chairman Dean Knudson, who was appointed by the Republican Assembly Speaker, proposed to codify as reliable the information suggesting the voters had moved and to deactivate the voters' registrations within seven business days after receiving the Ozaukee judge's order, which had not been filed as of Monday morning.

Both ideas were rejected.

"This commission has never been run this way — it has never acted capriciously and it has never acted in surprise like this," Mark Thomsen, a commissioner appointed by the Democratic Assembly Minority Leader, said about the quick action proposed by Knudson. Thomsen said the move would create an unconstitutional burden on voters at the polls.

"It would destroy our reputation we've worked so hard to build," he said.

Robert Spindell, a commissioner appointed by the Republican Senate Majority Leader, said requiring voters to re-register at the polls does not create such hurdles.

"I think it is an outrage to have 235,000 people who probably should not be on the voter rolls," he said. "It’s unnecessary ... this is really, unfortunately, a Republican-Democratic issue. The Republicans like to have clean rolls and the Democrats like to keep lots of people on the rolls."

The commission consists of three Republicans and three Democrats. The panel unanimously agreed earlier this year to give the letter recipients more than a year to change their voter registrations, before Spindell was appointed.

Attorney General Josh Kaul, a Democrat, is expected to seek an emergency stay of the judge's ruling when it is filed — potentially tying up the matter in courts for weeks or months.

Thomsen argued Monday the commission shouldn't take action until the courts resolve the dispute, to avoid confusion at the polls.

"For us to take this vote is simply grandstanding and trying to create points," he said. "I think all of us should respect those people who are properly registered and not treat them like they’re some piece of dirt. We do not have a right to impede someone."

Spindell reiterated the process to register is "very quick" and takes just minutes.

"To say we’re taking away people’s rights to vote is inaccurate," he said.

If people are removed from the rolls even though they did not move, it could create confusion and longer lines at the polls.

On the flip side, if the voters aren't removed from the voter rolls, some people who moved will be registered at the wrong address and could wind up going to the wrong polling place.

Patrick Marley of the Milwaukee Journal Sentinel contributed to this report.

Contact Molly Beck at molly.beck@jrn.com. Follow her on Twitter at @MollyBeck.