A federal judge in Indianapolis has blocked state election officials' plans to purge voters before the November election because they may be registered in another state.

Judge Tanya Walton Pratt of the U.S. District Court in Indianapolis granted an injunction that stops a new state law that would have kicked thousands of voters off the rolls based on a database that compares names with registered voters in other states.

Pratt said in a ruling issued Friday that the harm to wrongly purged voters far outweighs any possible harm to Indiana election officials seeking to protect the integrity of the process.

Voters, Pratt said, "face the imminent and irrevocable consequence of disenfranchisement of thousands of Indiana voters, only months before a federal election."

The state, Pratt ruled, "would face only the prospect of waiting until after adjudication of the merits of Plaintiffs’ challenge to implement extremely prejudicial aspects of an election bill that was passed only recently."

Pratt issued injunctions Friday in two separate lawsuits challenging the state law, one filed by Common Cause and another by the NAACP and the League of Women Voters.

Secretary of State Connie Lawson's office is consulting its lawyers to review options for a possible appeal.

“Voter list maintenance is a bi-partisan process in Indiana. Together, we work diligently to ensure our voter list is accurate," Lawson said in a statement emailed to IndyStar.

"We have never had a voter come forward who was incorrectly removed from the list."

The Indiana ruling may have been undercut Monday when the U.S. Supreme Court ruled 5-4 that Ohio did not violate federal laws by purging voters who haven't voted and failed to return residency confirmation notices.

Common Cause, the NAACP and the League of Women Voters challenged Indiana's use of the "Interstate Voter Registration Crosscheck" system, that under a new law allows election officials to immediately remove voters identified as having registered to vote in another state.

The system uses a database managed by the Kansas Secretary of State to match voters in different states based on first name, last name and date of birth.

“The court’s decision ensures that duly registered voters will not be improperly kicked off the rolls based on flawed Crosscheck data," Sophia Lakin, attorney with the American Civil Liberties Union's Voting Rights Project, said in a statement.

Jane Henegar, Executive Director, ACLU of Indiana, said election officials should promote voter engagement.

"Voting is our constitutional right," Henegar said in a statement, "and we must ensure every voice is heard.”

Call Star reporter Vic Ryckaert at (317) 444-2701. Follow him on Twitter: @VicRyc.

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