Idaho’s Effective Approach to Validating Voter Rolls

Key to ensuring trustworthy elections, voter registration lists (“voter rolls”) have received heightened scrutiny from both federal and state lawmakers in recent years.

Citizenship verification for voters was a particularly high priority for the Trump administration, Congressional Republicans, and conservative state legislators throughout 2025. Although President Donald J. Trump’s executive action requiring proof of citizenship was struck down in court—and Texas Rep. Chip Roy’s Safeguard American Voter Eligibility (SAVE) Act currently awaits action in the Senate—a number of states have enacted new laws to strengthen citizenship verification requirements for voters, either at registration or through list-maintenance practices.

Idaho is one of these states, and its approach provides useful insights as other states explore ways to ensure that only Americans vote in American elections.

Background

With just over 2 million residents, Idaho is a fast-growing Mountain West state and longtime Republican stronghold. Sixty-two percent of the state’s 1 million registered voters are Republican—compared to 25 percent unaffiliated and 12 percent Democrat—and Republicans have controlled both the executive and legislative branches at the Idaho State Capitol in Boise for the past three decades.

State law makes it abundantly clear that U.S. citizenship is required to vote in Idaho elections. The requirement is outlined in the Idaho Constitution and again in state statute, and voters approved a constitutional amendment in November 2024 asserting that non-citizens cannot participate in elections. Nevertheless, concerns about non-citizen voting persist among some Republicans, in part because Idaho (like most other states) does not require proof of citizenship when registering to vote. However, the state’s back-end citizenship verification process demonstrates how effective coordination and information sharing across governments can be for verifying the citizenship of Idaho’s registered voters and identifying individuals subject to removal from voter rolls.

Executive Order and Voter Validation Results

The catalyst for Idaho’s effort to strengthen protections against non-citizen voting was the executive order issued by Gov. Brad Little in July 2024, which put the “Only Citizens Will Vote Act” in place. The order empowered Secretary of State Phil McGrane to take “all necessary steps” to validate Idaho’s voter rolls and prevent non-citizens from voting. It also called on Sec. McGrane to coordinate with the State Transportation Department, State Police, and—most critically—the U.S. Department of Homeland Security (DHS).

The primary method for validating the voter rolls was comparing the list of 1.1 million registered voters to driver’s license data housed at the state’s motor vehicle division and to citizenship and immigration data available through the Systematic Alien Verification for Entitlement (SAVE) system administered by U.S. Citizenship and Immigration Services. Sec. McGrane’s office entered into a memorandum of agreement with the DHS to obtain access to this system, which allows government users to conduct citizenship verification searches across multiple federal government databases. Results from this review of federal and state databases included the identification and removal of 36 non-citizens from the voter list and additional evidence supporting the eligibility of the remaining 99.99 percent of registered Idaho voters.  

This exercise also highlighted the value of cross-referencing multiple databases and the importance of conducting additional research into records flagged as potential non-citizens. The initial review identified 700 individuals; however, that number dropped to 36 after further research and checking other sources. Understanding the limits of any single data source is essential to avoid removing voters who are, in fact, American citizens.

One example of an individual who could be flagged improperly is a naturalized citizen who obtained their driver’s license as a legally present non-citizen. If they did not update their record before registering to vote, then the motor vehicle division would still see them as a non-citizen. By checking with the SAVE system (which has access to naturalization records), an election official can confirm the individual’s eligibility, thereby avoiding avoid improper removal from voter rolls.

SAVE System Updates

Despite some data limitations and usability challenges, the SAVE system Idaho signed up to use in 2024 was an important piece of the state’s citizenship verification effort. Used in tandem with other data sources, SAVE helped Idaho strengthen their voter list maintenance program.  

Since returning to the White House earlier this year, the Trump administration has rolled out a series of changes that could make the SAVE system even more useful to election officials. These include eliminating user fees charged to state and local governments and allowing bulk queries using Social Security numbers to expand the pool of individuals identified. These improvements hold great potential to strengthen back-end citizenship verification across the nation, so long as users understand the tool’s limits and learn how to interpret the data properly.

A Successful Model for the Future

Recognizing the success of Gov. Little and Sec. McGrane’s initiative, lawmakers took action to enshrine the process in state law. Approved in April 2025, House Bill No. 339 formalizes information sharing practices across government by:

• Requiring the Secretary of State to obtain citizenship information from the federal government.
• Directing Idaho state agencies and local governments to provide information to the Secretary of State.
• Allowing the Secretary of State to enter into data-sharing agreements with other states to ensure voter list accuracy.

While many of these practices were already underway, this legislation was an important step toward ensuring they continue under future secretaries of state.

Idaho’s focus on strengthening the accuracy of its voter rolls without placing the burden on individual voters is a useful model for other states looking to take action on non-citizen voting. There will always be interest among lawmakers in proposals that require documentary proof of citizenship at registration, but Idaho’s experience demonstrates the value of back-end verification and the strength of the state’s existing protections against non-citizen voting.