This explainer was originally published by our news partners CalMatters. Be prepared for California’s primary: Sign up for CalMatters' free election newsletter and be the first to know when they update the CalMatters 2026 Voter Guide with information on key races.
What does California Proposition 39 do?
This initiative would require voters to show government-issued identification at the polls and order election officials to verify that all registered voters are U.S. citizens. Voters who cast a mail-in ballot would need to give the last four digits of a government ID, such as a driver’s license number. California currently requires residents to provide an identification card and Social Security number to register to vote, but does not request it at polling places.
What do supporters and opponents say?
- California Republican Party
- Reform California
- Uline CEO Richard Uihlein
Ballot text
This is how the proposition will appear on the ballot.
PROHIBITS CITIZENS FROM VOTING UNLESS THEY PRESENT GOVERNMENT ISSUED IDENTIFICATION. INITIATIVE CONSTITUTIONAL AMENDMENT. Invalidates mail ballots that do not have last four digits of designated government-issued identification number written on envelope. Prohibits in-person voting without presenting government-issued identification. Fiscal Impact: Costs of between tens of millions of dollars and low hundreds of millions of dollars each year to implement new voting requirements.
Source: California Secretary of State
