Taxpayer advocate Ted Costa blasted Wednesday a redistricting initiative that made the November ballot this week, saying it has too many loopholes to be effective.

Costa, CEO of Sacramento-based group People's Advocate, said a provision in the initiative would allow a commission created to redraw political boundaries the latitude to disregard certain criteria if a particular geographic area met a certain designation.

"Definitely, with the reformers on the sideline, we'll have to eventually amend this to make it work," said Costa, whose group was involved in both 1978's Proposition 13 tax reform measure and the 2003 recall of then-Gov. Gray Davis.

The initiative, which qualified for the Nov. 4 ballot Tuesday, would have a panel of state auditors choose a 14-member commission to redraw political maps in time for 2012 races.

It's backed by groups such as Common Cause and the AARP, as well as Gov. Arnold Schwarzenegger, a Republican, and former Controller Steve Westly, a Democrat.

According to the initiative's language, the auditors would pick the commission from a pool of applicants that would consist of registered voters who were not politically involved.

That commission would have five members from each of California's largest two political parties, and four members unaffiliated with those parties.

Costa said he's concerned about a provision in the criteria listed in the initiative that makes reference to "communities of interest" that should be made intact within a district without violating other criteria in the initiative.

"I would like to know how they define a ‘community of interest,'" Costa said.

The selection process for the commission is also flawed, Costa said, because he believes special-interest groups will stack the applicant pool to ensure that they have a say in how districts are drawn.

The initiative would affect state Assembly, Senate and Board of Equalization districts. Congressional districts would still be drawn by the State Legislature, but subject to the same criteria in the initiative.

Costa backed a ballot initiative of his own this year about political redistricting, but said he never circulated it for signatures because of a lack of funding.

Costa's measure would've had an 11-member commission with members chosen from a pool of statewide registered voters. Legislative leaders would've had some ability to strike members from a final pool of potential members, and defines a community of interest "as a group of residents who share similar interests including, but not limited to neighborhood, social, cultural, ethnic, geographic or economic interests."

California Assembly Speaker Emeritus Fabian Nunez has also said he wants to sponsor a ballot initiative for redistricting, with changes to term limits included. Nunez's office did return a call on whether he is still pursiung such an effort.

Costa said he believes Nunez, a Democrat, is still working on such an effort, noting that California Democratic Party leaders have attacked the qualified initiative, which has the support of such groups as Common Cause and the AARP as well as Gov. Arnold Schwarzenegger.

"Arnold doesn't have a clue on this," Costa said, explaining that the governor's office isn't aware of the loopholes Costa identified.