The Obama Administration has gone to the mat to try to prevent states from verifying the citizenship of their registered voters.

Registering and voting by non-citizens is a felony under federal law, and Florida has already found aliens on its voter rolls, some of whom voted in prior elections. Almost as soon as Florida announced that the Department of Homeland Security (DHS) would allow the state access to DHS databases, critics started complaining about the supposed inaccuracy of the DHS information (including an election law professor I debated on Los Angeles public radio).

Florida had been trying to get this access for the past year (as has Colorado). It had to sue DHS last month to force the agency to finally comply with federal law, which mandates that the government provide such citizenship verification information to the states.

The accuracy of the federal E-Verify system came up last year in Chamber of Commerce of the United States v. Whiting. E-Verify is the database that employers can check to confirm that new employees are either citizens or legal aliens authorized to work in the U.S. Even the Obama Administration, which was trying to prevent Arizona from mandating that employers use E-Verify, had to admit that E-Verify had a “successful track record…borne out by findings documenting the system’s accuracy.”

In fact, the Supreme Court noted that only in 0.3 percent of cases were individuals “confirmed as work authorized after contesting and resolving an initial non-confirmation.” In other words, there was only an initial 0.3 percent error rate in the E-Verify system, allowing more refined examination of those cases in which an error was claimed.

DHS agreed to give Florida access to the Systematic Alien Verification for Entitlements (SAVE) database in order to settle the lawsuit filed by the state. The DHS website says SAVE is designed to help “federal, state and local benefit-granting agencies, institutions, and licensing bureaus determine the immigration status of benefit applicants so only those entitled to benefits receive them.”

How accurate is SAVE? According to DHS, it can provide an applicant’s “immigration status within 3-5 seconds” electronically in 90 percent of cases. So we may rely on the SAVE system to determine whether someone is a citizen entitled to receive taxpayer-funded government benefits like welfare, but according to critics of what Florida is doing (such as the law professor I debated), we are not supposed to rely on it to determine whether that person is a citizen eligible to vote.

Another false claim made by opponents such as the ACLU is that this will lead to many eligible voters being purged. But neither Florida nor any other state is going to automatically or immediately remove a registered voter when they get a hit from the DHS database showing the person is not a citizen. In such cases, just like when employers use the E-Verify system for new employees, the voter will be notified of the discrepancy and given an opportunity to present current documents or information showing that the DHS records are wrong.

So why did the government fight so hard for so long to prevent states from accessing its very accurate and reliable databases? Why would the Obama Administration not want states finding out about non-citizens who are illegally registered or have them removed from the voter rolls?

There is little doubt that, based on prior prosecutions and other evidence that has surfaced (such as the 430 non-citizens in Colorado who recently asked the state to remove them from the voter rolls), states are going to find hundreds if not thousands of non-citizens illegally registered to vote when they start actually accessing DHS databases. And the federal government’s resistance to such state requests should concern all Americans who want clean, fair, and secure elections.

Hans A. von Spakovsky is a Senior Legal Fellow at The Heritage Foundation and co-author (with John Fund) of Who’s Counting? How Fraudsters and Bureaucrats Put Your Vote at Risk (Encounter Books, August 2012).