Assembly Bill 857, by Assemblyman Paul Fong, D-Cupertino, would have required anyone seeking to qualify an initiative for the statewide ballot to use non-paid volunteers to collect at least 10 percent of signatures.
The measure would have excluded from the 10 percent any signatures collected using direct mail, while counting signatures gathered by an employee or member of a non-profit organization.
Critics said the bill would give labor unions, with their large memberships, an unfair advantage in California's initiative wars.
In his veto message, Brown said "the initiative process is far from perfect and monied interests have historically manipulated it at will."
But the Democratic governor, who was successful in Proposition 30, his own initiative to raise taxes last year, said "requiring a specific threshold of signatures to be gathered by volunteers will not stop abuses by narrow special interests - particularly if 'volunteer' is defined with the broad exemptions as in this bill."
He said the measure "falls short of returning to the citizen-driven system originally envisioned in 1911," the year California adopted the initiative process.
The bill was supported by the California Labor Federation and several other union groups. According to a legislative analysis, proponents of the measure said it would preserve the intent of the initiative process by ensuring measures have broad community support.
The Howard Jarvis Taxpayers Association opposed the legislation, saying it would make the initiative process more difficult in part because of cumbersome record-keeping it would require.
PHOTO CREDIT: Gov. Jerry Brown campaigns for Proposition 30 at Sacramento City College on Oct. 18, 2012. The Sacramento Bee/Randy Pench