Gov. Jerry Brown on Monday vetoed an East Bay lawmaker's bill to ban per-signature pay for ballot-measure petition circulators.

Senate Bill 168, by state Sen. Ellen Corbett, D-San Leandro, would have forbidden paying ballot measure petition signature gatherers on a per-signature basis, which she said would reduce fraud by reducing the temptation to pad out petitions with bogus names.

In his veto message, Brown wrote he understands the potential abuses under the current system but sees two flaws in Corbett's bill.

First, it would bar groups from even setting targets or quotas for signature gatherers; he said making productivity goals into a crime seems impractical. And second, per-signature payment often is the most cost-effective way to get enough signatures to qualify for the ballot, he wrote: "Eliminating this option will drive up the cost of circulating ballot measures, thereby further favoring the wealthiest interests."

"I am not persuaded that the unintended consequences won't be worse than the abuses the bill aims to prevent," Brown wrote.

The bill's foes, including the California Chamber of Commerce, had said there's little evidence of such fraud, but Secretary of State Debra Bowen, the state's chief elections officer, was among those who endorsed the bill. Corbett issued a statement saying she's disappointed, but will keep working on ways to reduce electoral fraud.

"Direct democracy can only work if voters know what they are signing and voting upon," she said. "This law has proved to be an effective remedy in other states to help prevent fraud without making it more difficult to put initiatives on the ballot."

The state Senate passed SB 168 in May on a 23-15 vote, and the Assembly passed it in July on a 48-28 vote.

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