Department of Homeland Security Secretary Markwayne Mullin pressed state election officials on Friday to "scrub" their voter rolls and take other steps to update election security systems, alleging that hundreds of thousands of non-citizens are registered to vote across the U.S. --- 250,000 of which the agency claimed came from four states.

DHS is now pushing states to use the expanded SAVE System -- a tool maintained by U.S. Citizenship and Immigration Services originally intended to determine eligibility for government benefits -- to assess their voter rolls, according to a DHS report released by the White House on Thursday night.

Mullin threatens to withhold aid from states that don't comply with DHS election directives

But some experts and state election officials have flagged faulty data using the system in the past.

It is unclear whether DHS used the system to tally up the alleged 250,000 non-citizen registered voters across four states. In his remarks to reporters on Friday, Mullin did not explain exactly how DHS verified its data.

But the agency has repeatedly called on states to use SAVE to audit their voter rolls. The White House referred questions about the report to the DHS. In response to detailed questions about the report, DHS referred back to a Friday social media post from Mullin.

The SAVE (Systematic Alien Verification for Entitlements) system is not a comprehensive record of American citizens; it is a tool used to search collections of federal records and databases to assist in verifying immigration and citizenship status.

Prior to 2025, the system was restricted to querying known immigrants, non-citizens and naturalized citizens against DHS data to verify their status.

Last year, the Trump administration expanded the SAVE system to verify the citizenship status of all people registered to vote -- including natural-born citizens.

A core part of that effort included DHS expanding the ability to query the SAVE system using Social Security numbers and Social Security Administration (SSA) data, enabling broader, bulk searches of state voter rolls using more basic demographic information.