L.A. County Supervisor Zev Yaroslavsky, an MTA board member, called the governor's proposal "legally questionable," "wrong-headed" and "poor public policy."
"The fact that this scheme is likely to be overturned by the court, as it has in the past, means that the proposal itself has no validity," he added.
The administration declined to comment on the proposal. Schwarzenegger will officially unveil his budget plan to close California's projected $20.7-billion deficit in early January.
Transit advocates, joined by local government groups, announced Wednesday that they are starting to gather signatures for a measure, aimed for the November 2010 ballot, to further wall off their money from Sacramento.
The California Supreme Court seemingly put an end to the transit raids only months ago, ordering the state to repay the more than $3 billion in gasoline sales taxes that it had taken since 2007.