President Donald Trump's administration also supported Ohio's position.
What's more, they said, they anxious that the ruling now gives other states a blueprint from which to conduct their own voter purges. "In Ohio, and still in most states, that's not the case", Simon explained.
In 2006, the State Board of Elections and then-Kentucky Secretary of State Trey Grayson faced legal action for unilaterally removing voters from the rolls.
"Voters have been struck from the rolls in Democratic-leaning neighborhoods at roughly twice the rate as in Republican neighborhoods", the study found. "Neighborhoods that have a high proportion of poor, African-American residents are hit the hardest".
Ohio's rules, which use voter inactivity to trigger a process that can lead to their removal from the voter rolls, are similar to those of states like Pennsylvania, West Virginia and Georgia. "So states may attempt to adopt these practices, but they need to be careful that they're not discriminatory and we will be watching for any discriminatory impact that these practices have".
The case was initially dismissed by a district court, but an appeals court sent it back to be reconsidered once the Supreme Court made its decision in the OH case, as well for "a more detailed analysis of the First Amendment question". "In the appeals court, the Obama administration filed a brief supporting Mr. Harmon". Franklin Circuit Judge Judge Phillip Shepherd ruled Grayson and the State Board of Elections illegally removed more than 8,100 Kentucky voters from the rolls.
But in recent years, some purges have been viewed through a more partisan lens.More news: Donald Trump Says That Melania Had a ‘Big Operation’
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The challengers, represented by liberal advocacy group Demos and the American Civil Liberties Union, sued Husted in 2016 to end the policy. Alabama put 340,000 voters on its inactive list the same year. That law states that "nothing in this paragraph may be construed to prohibit a state from using the procedures described" in the motor voter law.
Ohio's contested voter purge stems from an inoffensive requirement in federal law that states have to make an effort to keep their voter rolls in good shape by removing people who have moved or died. "The only question before us is whether it violates federal law".
Facing those sorts of issues, OH wanted to try to remove people who failed to vote in a six-year period and who failed to return a notice, figuring at that point they had probably moved and the registration was invalid. That's because minorities, young people and those with lower incomes are more likely to be disenfranchised by the state's policy.
"We are anxious that would-be vote suppressors will read too much into it and conclude that aggressive purges or unreasonable purges would be tolerated", Perez said in an interview.
"Today's ruling empowers local officials and concerned parties to utilize the NVRA to ensure the most accurate and reliable voter rolls possible", he said in a statement.
The Crosscheck program, which involves 26 states around the country, has come under increasing scrutiny in recent years as some states accuse it of improperly flagging eligible voters. States taking an intermediate approach send cards to people who have turned in driver's licenses or who haven't voted for some time period. If a voter responds, their information is updated and they remain on the list.
Tennessee has eliminated the practice of purging voters based on a lapse in voting history. Voting rights activists rallied to oppose voter roll purges as the Supreme Court hears oral arguments in the Husted v. Apparently I'm getting better at this Supreme Court prediction stuff!