A former Republican congressman and four others filed suit Thursday with the California Supreme Court, alleging that that state's newly drawn congressional districts are illegal and unconstitutional.

The suit by Mariposa Republican George Radanovich, who left Congress in January, asks the court to throw out the 53 new congressional boundaries and appoint a special master to draw new ones.

The legal challenge comes nearly a month after opponents of the congressional maps announced a referendum drive aimed at letting voters decide the fate of the new maps. That drive apparently has stalled.

California's congressional, legislative and Board of Equalization districts were drawn for the first time this year by an independent citizens commission, rather than by the Legislature, under terms of ballot initiatives passed in 2008 and 2010.

"California voters approved two initiatives designed to finally remove politics and back room deals from redistricting. Unfortunately, the Citizens Redistricting Commission failed miserably in that respect," Radanovich said in a written statement.

Specifically, Radanovich's suit targets three Los Angeles districts, claiming that lines were drawn to protect three incumbents in violation of federal law and the state constitution.

The commission failed to meet its obligation under the federal Voting Rights Act to ensure that one or two of those congressional districts had a majority of African American voters, the lawsuit contends.

"The only apparent reason for such neglect by the commission was to enable the three current incumbents to remain in office," Carlos Rodriguez, a GOP strategist, said in a statement announcing the suit.

In somewhat of a ripple effect, the failure to properly draw lines for those three Los Angeles congressional districts denied Latinos elsewhere in the county one – perhaps two – additional Latino-majority districts, according to Rodriguez.

The suit also takes aim at the 47th Congressional District, which "begins at the port of Long Beach and then wanders far into central Orange County to absorb portions of Garden Grove and Westminster," the suit said. "This divides the Orange County Asian community." Rodriguez could not be reached immediately Thursday for further comment.

A separate coalition of Republican Party interests, led by Sacramento-based strategist David Gilliard, has started a referendum drive and filed suit against the state's 40 new state Senate districts.

The commission consistently has said that its members are confident their maps will withstand any legal challenge.

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