Gov. Arnold Schwarzenegger signed a law requiring that all electronic voting machines produce paper records of every ballot cast, beginning in 2006.
Under the bill, signed Monday, voters will not be able to touch or keep the records; instead, election officials will put them in lock boxes in case a recount becomes necessary.
Computer scientists and voter advocates have warned that touchscreens and other electronic voting machinery are vulnerable to hackers, software bugs and hardware failures, and that a paper trail is needed in case something goes wrong.
Legislators in nearly two dozen states have introduced similar bills. New Hampshire, Illinois and Oregon have laws requiring paper backups but those states have few, if any, touchscreen voting terminals.
By contrast, about 4.5 million registered voters in 10 California counties are eligible to vote on paperless terminals in November, representing one in 10 of all voters nationwide who cast electronic ballots.
“This will definitely help advance the paper trail issue elsewhere,” said Kim Alexander, president of the California Voter Foundation. “California represents a huge part of the voting equipment market, and all the major vendors have equipment here. If they want to keep their business here, they’ll have to come up with a paper trail feature.”