A federal judge has delivered a major blow to the Trump administration’s ambitious plan to build a centralized database containing Social Security numbers and sensitive citizenship information on millions of Americans, blocking what critics called a sweeping and potentially unlawful surveillance tool aimed at overhauling federal elections.

U.S. District Judge Sparkle Sooknanan ruled Monday that officials “haphazardly combined and repurposed the private information of millions of Americans, including citizenship data that they knew to be unreliable,” in response to President Trump’s March executive order.

The order had directed the creation of a “State Citizenship List” using data from the Social Security Administration, naturalization records, and the Department of Homeland Security’s SAVE database, with the goal of restricting mail-in ballots and tightening voter eligibility checks.

In a strongly worded 75-page opinion, Judge Sooknanan accused multiple agencies of trampling on privacy rights and threatening the fundamental right to vote. She highlighted how states had already begun using the flawed data to remove U.S. citizens from voter rolls, calling the entire effort a clear violation of federal laws including the Social Security Act, Privacy Act, and Administrative Procedure Act.

The lawsuit was brought by the League of Women Voters, which celebrated the decision as a “critical win for voting rights,” protecting millions from baseless investigations and improper purges.

This ruling strikes directly at the heart of the administration’s push for stricter election integrity measures. While the White House and DHS have not yet commented, the decision raises fresh questions about the balance between security and privacy in American democracy — and whether such expansive data collection efforts can survive legal scrutiny.

For now, the creation of this controversial voter database has been halted, but the broader battle over election rules, citizenship verification, and government data use is far from over.