Voters — Election Security Glossary

An election has legitimate authority only when it includes all eligible voters and excludes ineligible ones. That threshold (who votes and who does not) is one of the most heavily regulated aspects of election administration, embedded in federal and state law, and defended through documentation, verification, and procedural safeguards. Voter eligibility and the protection of voting rights sit in constant tension with each other, and the terminology of voter administration reflects that dynamic.

The legal foundation is straightforward in principle: to vote, a person must be a U.S. citizen, of voting age, a state resident, and not legally disqualified. But eligibility is not self-evident at the polling place, and the practical challenge of election administration is verifying that a person who appears genuinely meets those requirements without creating barriers that disenfranchise eligible voters.

Three policy questions have reshaped voter administration in recent decades. First, voter identification: must a voter present government-issued photo identification, or can other documents suffice, or no documentation at all? The approach adopted by each state is a political and practical choice, balancing the need to verify identity against barriers that requirements can create for eligible voters without appropriate documentation. Second, provisional ballots. If a voter's eligibility is uncertain, can they cast a ballot provisionally and have it counted later if eligibility is confirmed? Third, voter roll maintenance. How aggressively should election officials purge outdated or inaccurate registration data? Each of these questions has no universal answer. They are policy choices embedded in law and administered through procedures that must be transparent and verifiable.

Beyond eligibility, voter protection extends to ballot secrecy (ensuring that how a person votes is not revealed to others) and accessibility, ensuring that voters with disabilities have equal ability to vote privately and independently. These protections are federal law under the Americans with Disabilities Act and HAVA Title III.