Some 7.2 million people are registered to vote in more than one state, according to data obtained this month by a voter-integrity law firm called the Public Interest Legal Foundation.

The data come from the Interstate Crosscheck system, a 28-state consortium run by Kansas. The numbers largely are unchanged from 2014, when the database had 7.3 million double-registered voters.

“Let’s check. If that’s the case, at least we’ll have appropriate measures to make such a statement.”

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Considering that nearly half of the states — including the three most populous — do not participate in the voluntary system, Public Interest Legal Foundation spokesman Logan Churchwell said the total number of people in America registered to vote in more than one state could be twice as high or greater.

“It could be 20 million,” he said.

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It is not against the law for someone to be registered to vote in more than one state. But integrity advocates worry that inattention to the voter rolls opens the door to possible fraud. It is illegal to vote in more than one state in the same election.

“It’s kindling, essentially,” Churchwell said.

Many voting officials downplay the significance of voters with double registration, arguing that a tiny number of voters try to cast multiple ballots. But Catherine Engelbrecht, founder of True the Vote, said America never has conducted a comprehensive, nationwide analysis to test that theory.

“Let’s check,” she said. “If that’s the case, at least we’ll have appropriate measures to make such a statement.”

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That may soon occur. President Donald Trump last week appointed a commission to examine voter fraud, naming as vice chairman Kansas Secretary of State Kris Kobach, who created the Interstate Crosscheck system.

[lz_table title=”Double Voter Registration” source=”Interstate Crosscheck”]States with the most voters registered in another state*

|State,Voters

Georgia,660.7K

North Carolina,561.8K

Illinois,542.1K

Indiana,516.7K

Ohio,479.1K

Michigan,418K

Kentucky,371.8K

South Carolina,368.2K

Virginia,354.5K

Tennessee,296.5K

|

* Only in 28 participating states

[/lz_table]

The system collects voter registration data from participating states and merges them, cross-referencing names, dates of birth and Social Security numbers for possible matches. In addition to multiple interstate registrations, the system also flags people who may be registered in more than one jurisdiction within their state or have invalid dates of birth, invalid Social Security numbers, or other defects.

Once the system identifies double registration, it then falls to those states to take action. Both states with a common registered voter must track down the voter, determine which address is valid, and then update the rolls.

It can take years, which is one reason why the overall numbers have not changed in three years, Churchwell said. He said new names constantly get added as old ones are removed. And if a flagged voter does not respond, it bogs down efforts, he said.

“A lot of this hinges on whether the voter participates in this process,” he said.

Alabama Secretary of State John Merrill said his state participates both in the Kansas-run system and a similar program run by the non-profit Electronic Registration Information Center.

“It gives us another tool to effectively remove people from rolls that don’t belong there,” he said.

Merrill said both systems supplement the regular purge process that registrars regularly engage in to keep the rolls accurate. That includes checking death records, change-of-address records maintained by the U.S. Postal Service, data from the state prison system, and other databases.

Merrill said information gathered from the state consortiums and the normal culling process have helped identify possible fraud. He has referred some cases to the state attorney general’s office and others to local district attorneys for possible prosecution.

Alabama has not always maintained a stellar record when it comes to maintaining clear voter registration rolls. It was one of 11 states threatened with lawsuits last month by Judicial Watch for having counties with more registered voters than voting-eligible adults. The Public Interest Legal Foundation in 2015 threatened to sue 10 Alabama counties.

Merrill said he makes sure that Alabama counties comply with the law.

“They may or may not be initially cooperative,” he said. “But they will be cooperative in the end.”

The Public Interest Legal Foundation has attempted to force voter registrars to be more aggressive in cleaning up their rolls, filing a number of lawsuits across the country. Churchwell said cooperation from the federal government would help, both in helping states identify non-citizens and in pushing voter registrar’s offices to clean up the rolls. He noted that the Department of Justice under President Barack Obama did not sue a single jurisdiction over inaccurate or outdated voter registration lists.

“That created a culture of unaccountability,” he said.

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Engelbrecht said modern technology could greatly improve the voting system in America. Old technology makes it difficult to keep up with voters who move.

“It’s a lengthy process,” she said. “The frustrating thing is that it doesn’t need to be … It’s a lack of political will and assignment of priority.”

Engelbrecht said she supports a national database run by the states, perhaps supported by federal grants, that alerts elections officials in any state whenever someone already registered in another state signed up to vote. She advocated adoption of “blockchain” technology that would allow states to keep track of voters with an encrypted system that would make tampering nearly impossible.

“What it really boils down to is that we have a system that is built on honor,” she said. “You don’t need a lot of fraud [to impact elections]. You just need a little fraud in the right places.”