When Scott Hoen ran to be the chief election official of Carson City, Nev., two years ago, he campaigned on “election integrity,” promising to make sure voter registration lists were accurate.

In the chaotic aftermath of the 2020 presidential election, he believed that too many of his fellow Republicans were convinced that there was widespread voter fraud. By keeping voter rolls current, Hoen thought he could restore voter trust in his county’s election system.

He won. And every day since he took office, he and his staff have tried to keep that focus, using data from all levels of government to remove voters who have moved or died from the active voter list.

Hoen was surprised, then, to be named in a lawsuit the Republican National Committee and the Nevada Republican Party filed in March against him, four other Nevada county clerks and the secretary of state. The lawsuit alleges that five localities had “inordinately high” voter registration rates and that the state is violating federal law by not having what are known as “clean” voter rolls.

Hoen said the lawsuit is “unfortunate” and “a distraction” in a pivotal election year. The state responded by saying the data Republicans used in the lawsuit is “highly flawed” and that the RNC’s analysis was like “comparing apples to orangutans.” Former President Donald Trump’s lawyers asserted without evidence that more than 1,500 dead Nevadans voted in 2020 and that an additional 42,000 in the state voted twice.

The Nevada lawsuit is just one example of the tactics Republicans and conservative activists are using ahead of November’s presidential election, as they seek to purge voter rolls of allegedly ineligible voters. The efforts — including a lawsuit in Hawaii over the release of voter registration lists — have election experts worried about voter access.

Changing a voter’s status is routine for election officials. Like others across the country, Hoen moves voters from active to inactive when election mail is repeatedly returned or when he gets death notices, and moves them to active status when he gets motor vehicle records for newly registered voters.

Nevada also is a member of the Electronic Registration Information Center, known commonly as ERIC, an interstate data-sharing pact that seeks to help states keep updated voter lists. Recently, ERIC has been a target of conspiracy theories that led to an exodus of nine Republican-led states over the past two years.

“Who knows where they got their numbers? But they didn’t consult me or ask me, or no one’s talked to me about what we do with voter roll maintenance,” Hoen said of the lawsuit in an interview with Stateline. “We do everything we can, per the law, to keep our voter rolls as plain as possible.”

The RNC filed a similar lawsuit in March against Michigan. Conservative groups have recently filed lawsuits in many other states, seeking access to state voter registration lists and claiming they might be bloated.

Some states, including Georgia and Indiana, have made it easier to remove registered voters from the rolls. And groups aligned with former President Donald Trump have launched data analysis tools to aid in large-scale challenges to voter registrations.

Election experts say maintaining accurate voter lists is a key part of election administration, but they are concerned that the challenges and lawsuits could bolster unfounded claims of rampant voter fraud. They also worry it could create undue hardships on voters who might have to prove their eligibility close to an election, and bog down election offices with frivolous data requests and challenges.

“When you see efforts to do mass challenges in the midst of the presidential primaries and months before a major election, you’ve got to wonder whether the intent is to create chaos and confusion amongst voters rather than legitimate list maintenance,” said David Becker, founder and executive director of the Center for Election Innovation &Research, a nonpartisan organization that advises local election officials nationwide.

Voter challenges aren’t inherently bad, he said. There are legitimate reasons to bring a challenge: A neighbor may have died or moved away, for example, and a voter wants to let an election official know.

But Becker is concerned that mass challenges and lawsuits could make voter lists less accurate, which could lead to problems at polling places, more provisional ballots and longer lines — creating the conditions for candidates to claim an election was stolen.

Challenges to registrations are getting an assist from court cases that are making voter rolls public.

Since 2020 there have “been a lot of questions” surrounding elections, said Lauren Bowman Bis, director of communications and engagement for the Public Interest Legal Foundation, one of several conservative groups that have sued states to release voter registration lists.

Transparency in elections is crucial for people to have more confidence in the system, she added. By gaining access to voter names, addresses and party registration, groups like Bis’ can check states to make sure lists are accurate and they’re not sending multiple ballots to people or are ensuring dead people are removed from the rolls.

Bis has gone to cemeteries in Michigan where, she said, she has seen the names of active voters on tombstones.

The foundation, often known as PILF, has active lawsuits in Hawaii, Michigan and South Carolina over their voter roll maintenance. Over the past four years, they have successfully sued Illinois and Maryland and gained access to those states’ voter lists.

In February a federal appeals court ruled that Maine had to release its voter rolls to the Public Interest Legal Foundation. The group has appealed a ruling in Michigan that it lost in a district court in March, arguing the state did not make a “reasonable effort” to clean its rolls.

Another conservative group that posts voter rolls online, the Voter Reference Foundation, sued Pennsylvania in February over access to its registration lists. The group did not respond to emailed questions.

“The voter roll really is the most essential election integrity document,” said Bis. “We’re just trying to make sure that federal law is enforced in states or localities where we find election officials aren’t doing what they are required to by law to have a secure election that people can have confidence in the results.”

But the disagreement over these efforts once again comes down to the data — the methodology that plaintiffs use in their complaints.

Conservative groups sometimes compare the current number of registered voters to an outdated estimate of the number of voting-age citizens in that jurisdiction, said Eliza Sweren-Becker, a senior counsel at the Brennan Center for Justice, a voting rights group housed at the New York University School of Law.

“You’re really comparing apples and oranges in suggesting that there’s something improper with high voter registration rates,” she said. “We should hope and expect that all eligible Americans who want to participate in our democratic system are registered to vote and can stay on the rolls.”