President Donald Trump has signed a controversial executive order titled Preserving and Protecting the Integrity of American Elections, which requires voters to show proof of U.S. citizenship when registering for federal elections. The order, part of Trump’s flurry of nearly 100 executive actions since taking office in January, has sparked widespread debate and legal scrutiny.

The administration argues the new requirement is essential to prevent voter fraud and to align U.S. election standards with those of other countries that use biometric or strict ID systems. Acceptable documents include a U.S. passport, REAL ID-compliant driver’s license, military ID, or other approved government-issued ID. Without them, citizens will be barred from voting in federal elections.

The order also tightens rules around mail-in voting, mandating that all ballots must be received—not just postmarked—by Election Day. This change would override current policies in 18 states and Puerto Rico.

Critics argue the order is unconstitutional and could disenfranchise millions of voters, particularly minorities, the elderly, and low-income Americans. Legal experts expect swift challenges, with some calling it an executive overreach that undermines state control over elections. Additionally, the order threatens to withhold federal funding from noncompliant states, raising further concerns about federal coercion.

While Trump insists the order is necessary to eliminate election fraud, opponents—including state officials and voting rights advocates—say it amounts to voter suppression. With Congress having previously rejected similar legislation, the fate of the order will likely be decided in the courts.