COLUMBUS, Ohio (AP) — A lawsuit filed Thursday challenges Ohio’s newly drawn state legislative districts as giving an extreme and unfair advantage to the Republican Party, which controls the state’s new redistricting commission.

The American Civil Liberties Union, its Ohio arm and a law firm filed the litigation on behalf of the League of Women Voters of Ohio, the Ohio Chapter of the A. Philip Randolph Institute and several individual voters against members of the commission.

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The groups say the suit is the first such legal action in the nation against district maps redrawn using results of the 2020 census.

It targets a map the powerful new Ohio Redistricting Commission passed in a 5-2 vote along party lines last week. The panel failed to reach the bipartisan consensus necessary to pass the normal 10-year map of state House and Senate districts envisioned under redistricting and so was forced to create a four-year map.

Republican Senate President Matt Huffman, who took a leading role in crafting the maps, has defended the maps as constitutionally compliant and rejected the idea they are gerrymandered.

Freda Levenson, legal director of the ACLU of Ohio, called the maps an “extreme partisan gerrymander” that flagrantly violates the redistricting rules laid out in the Ohio Constitution, after approval by a strong majority of Ohio voters.

“The blatant defiance of the reforms that were overwhelmingly passed by Ohio voters just six years ago is not only a violation of law, but is also a slap in the face to the people of this state,” Levenson said in a statement. “We are going to this state’s highest court to ensure that Ohio voters are able to have a voice in their government.”

According to the suit, Republicans have won a vote share of between 46.2% and 59.7% over the past decade, yet the map draws 67% of the House districts and 69% of Senate districts to favor Republicans.

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Under Ohio’s new redistricting system, the Ohio Supreme Court has original and exclusive jurisdiction over legal disputes over the map. In a briefing with reporters Thursday, plaintiffs and their lawyers said the case must be expedited so that any new map that’s ordered can be completed by January, before 2022 candidates must declare for office Feb. 2.

Huffman pushed back against accusations of gerrymandering in a Friday guest column in The Columbus Dispatch as based on “a false narrative.”

He said the map is “both constitutional and compliant” with the directives voters approved, and that it keeps districts compact and communities together.

“Make no mistake, special interest groups tried very hard to undermine the process by pressuring members to accept so-called ‘representational fairness,’” he wrote. “This is simply the basic definition of gerrymandering, as these groups insist on telling Ohio voters what is fair.”

Levenson said representational fairness isn’t reverse gerrymandering to favor the other party — in Ohio’s case, Democrats — rather it requires maps to represent each parties’ vote share fairly.

“Yes, it would improve the Democrats’ representation in the (Ohio) General Assembly if they won, but that would be to achieve fairness, not to achieve an unfair advantage,” Levenson said. “It would be to undo an unfair advantage, obtained because people drawing the map do the map to favor themselves.”

Representatives of both the ACLU and the League of Women Voters emphasized that they are nonpartisan organizations that have fought maps gerrymandered to favor both Republicans and Democrats.

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