A whistleblower has come forward with allegations about the Department of Homeland Security's methods for investigating non-citizen voting. The claims suggest the department is using questionable tactics based on unreliable data. This has led to accusations of an indiscriminate operation that could wrongly target eligible voters.

The whistleblower's revelations were published in a document by prominent Senate Democrats. The issue has gained attention as President Donald Trump has made finding evidence of large-scale non-citizen voting a priority, despite studies showing it is extremely rare.

Further details about the allegations and the department's response are available from the source, including information about training materials for agents.