South Dakota and Utah gave final legislative approval this week to proof-of-citizenship requirements for voter registration, while Florida, Michigan, and Missouri advanced similar measures, as Republican-controlled states pressed ahead without waiting for a deadlocked U.S. Senate. The federal Safeguard American Voter Eligibility Act — backed by President Donald Trump and passed by the Republican-led House on a mostly party-line vote last month — has stalled in the Senate under a Democratic filibuster threat. Federal law already bars noncitizens from voting in U.S. elections; current registration requires applicants to affirm citizenship under penalty of perjury.

The state-level push echoes a recurring pattern in which legislatures move ahead on voting-access measures when federal action stalls, a dynamic with a documented legal record: a Kansas proof-of-citizenship law blocked more than 31,000 U.S. citizens from registering to vote before federal courts declared it an unconstitutional burden on voting rights in 2018.

South Dakota and Utah enacted proof-of-citizenship voting requirements this week, with legislators in Florida, Missouri, and Michigan also advancing measures — even as President Donald Trump’s push for a federal version stalled in the U.S. Senate.

The Safeguard American Voter Eligibility Act, known as the SAVE America Act, would require documentary proof of U.S. citizenship — such as a passport, naturalization certificate, or a birth certificate combined with government-issued photo identification — to register to vote in federal elections. It would also mandate photo identification to cast a ballot. The Republican-led House passed the legislation last month on a mostly party-line vote, but it has stalled in the Senate under a filibuster threat from Democrats.

Federal law already prohibits noncitizens from voting in U.S. elections; violators face fines, imprisonment, and potential deportation. When registering, applicants affirm citizenship under penalty of perjury. Trump has argued that affirmation alone is insufficient.

What the new state laws do

South Dakota and Utah passed a two-tier system modeled after Arizona, where voters who provide citizenship documentation may vote in all elections, while those who do not may cast ballots only in federal races for president, U.S. Senate, and U.S. House. Arizona implemented its system after the U.S. Supreme Court ruled in 2013 that the state could not require citizenship documentation for federal elections.

The bills in South Dakota and Utah would take effect upon a governor’s signature, potentially applying to newly registered voters ahead of November.

Utah’s bill goes further, directing election officials to use an online service from U.S. Immigration and Customs Enforcement to check the citizenship status of existing voters. Those flagged by the system would receive notices requesting proof of citizenship to remain eligible to vote in all elections.

Florida and Michigan take a different approach

Neither the Florida nor Michigan measures would require documentation at the point of registration. Instead, both create a behind-the-scenes review of existing voter rolls.

The Florida House passed legislation requiring election officials to verify the citizenship of every registered voter against the state’s driver’s license database. Any voter whose citizenship could not be confirmed through that database would then be required to submit documentary proof.

The Michigan measure would authorize the secretary of state to cross-reference driver’s license records, juror records, and data from the federal Department of Homeland Security and the Social Security Administration. Registered voters flagged by the review would be removed from the rolls if they cannot produce proof of citizenship.

Supporters of the Michigan ballot initiative submitted 750,000 petition signatures this week seeking to place a constitutional amendment before voters in November. Paul Jacob, chairman of Americans for Citizen Voting, which backs the Michigan measure, said the 2024 case of a University of Michigan student from China — who was charged with perjury and attempted illegal voting after registering with a student identification card before eventually fleeing the country — helped catalyze the effort.

“We want a system we can have confidence in,” Jacob said. “The way you avoid big problems in elections is to fix the small problems when they rise up and present themselves.”

Concerns about documentation requirements

Trump and some fellow Republicans have raised alarms for several years about noncitizens voting. Evidence of people doing so is rare, according to the Associated Press.

Voting rights advocates warn that documentary requirements create practical barriers for eligible U.S. citizens. During debate in the Florida House, Democratic state Rep. Ashley Gantt said her aunt was born at home in South Carolina during a period when some hospitals refused to admit Black patients, leaving her without a birth certificate and with difficulty demonstrating citizenship.

Michelle Kanter Cohen, policy director and senior counsel at the nonprofit Fair Elections Center, said a proof-of-citizenship law “would stop many thousands — if not more — U.S. citizens from voting in Florida. It requires documentation that a lot of eligible citizens don’t have, or don’t have access to.”

A 2024 report by the Center for Democracy and Civic Engagement at the University of Maryland found that approximately 21 million people — 9% of voting-age citizens — lack documentary proof of citizenship or cannot easily obtain it.

States that have enacted proof-of-citizenship requirements have routinely faced lawsuits.

Kansas adopted such a law approximately 15 years ago. More than 31,000 U.S. citizens were subsequently blocked from registering to vote. Federal courts declared the law an unconstitutional burden on voting rights; it has not been enforced since 2018.

New Hampshire and Louisiana both passed proof-of-citizenship laws two years ago, each prompting litigation. New Hampshire’s law went to trial last month and is awaiting a ruling. Louisiana’s election commissioner acknowledged in a December court filing that the state’s requirement has not been enforced.

A legal challenge to a Wyoming proof-of-citizenship law passed last year was dismissed after a federal court ruled the plaintiff organization lacked standing to sue.