LANSING – Michigan would get new state legislative and congressional maps for the 2020 election — and even special state Senate elections — under a sweeping federal court judgment Thursday to end a gerrymandering lawsuit.

A three-judge federal panel ordered the state Legislature to redraw at least 34 districts for the 2020 election in a lawsuit brought by the Michigan League of Women Voters. Though the ruling only explicitly affects those 34 districts, the effects of the ruling are sure to be broader since redrawing any district can also impact neighboring districts.

And in what may be an unprecedented aspect of the decision, it requires special state Senate elections to be held in 2020, instead of 2022 as scheduled. State senate elections are normally held every four years to coincide with elections for governor, but the lawsuit targeted 10 of Michigan's 38 Senate districts, and the federal panel ruled that all 10 were unlawfully gerrymandered.

An appeal, which Michigan Republicans promised soon after the decision was released, would go directly to the U.S. Supreme Court.

"Today, this court joins the growing chorus of federal courts that have, in recent years, held that partisan gerrymandering is unconstitutional," said the opinion signed by Circuit Judge Eric Clay, who was appointed by former Democratic President Bill Clinton.

The ruling comes after newly elected Democratic Secretary of State Jocelyn Benson offered a much more modest proposal to settle the lawsuit. Republicans successfully fought the proposed settlement, which would not have affected state Senate or congressional districts in 2020, forcing the entire case to go to trial.

Benson issued a statement saying she respects the court's decision.

Laura Cox, chairwoman of the Michigan Republican Party, said the party disagrees with the ruling and "will support an appeal to uphold the will of Michigan voters.”

Senate Majority Leader Mike Shirkey, R-Clarklake, said an appeal is planned.

Michigan's gerrymandered districts, approved by Republicans who controlled both chambers of the Legislature, plus the governor's office, deliberately discriminate against Democratic voters by diluting the power of their votes, Clay wrote on behalf of the unanimous panel.

Republicans "enjoyed great success in Michigan's 2012 elections," the first election using new lines they drew after the 2010 census, "due in large parts to the efforts of Republican legislators and map-drawers," the opinion said.

"The evidence points to only one conclusion: partisan considerations played a central role in every aspect of the redistricting process."

The judges gave the GOP-led Legislature until Aug. 1 to submit new maps, which would need the signature of Democratic Gov. Gretchen Whitmer.

If that deadline is missed, the court will draw the new maps, under the ruling.

Read more:

Court rejects SOS Benson's proposed settlement of gerrymandering lawsuit

SOS Benson's modest proposal to right gerrymandering wrongs

The ruling will only affect the 2020 election because Michigan voters approved a new independent citizen redistricting commission to draw election lines for the 2022 election and beyond, following completion of the 2020 census.

Voters Not Politicians, the group that led the ballot drive to create the redistricting commission, applauded the ruling.

"We agree with the court ruling that existing maps were drawn with political interests in mind, rather than accurately representing Michigan voters," said Nancy Wang, the group's executive director.

"We hope the legislature will draw this set of interim maps to represent voters, not politicians, just like 61% of Michigan voters supported in the last election."

Judy Karandjeff, president of the League of Women Voters of Michigan, said she was pleased with the opinion and looks "forward to remedying all of these districts in time for the 2020 elections."

The federal panel — Clay of the 6th U.S. Circuit Court of Appeals, U.S. District Judge Denise Page Hood of Michigan's eastern district and U.S. District Judge Gordon Quist of Michigan's western district — said those involved in the 2011 redistricting effort elevated "partisan considerations" at every step.

"Their primary goal was to draw maps that advantaged Republicans, disadvantaged Democrats, and ensured that Republicans could enjoy durable majorities in Michigan's congressional delegation and in both chambers of the Michigan legislature for the entire decade," the judges wrote.

The judges based that ruling on emails and other records produced during the closed-door redistricting process that was managed by Republicans and their consultants.

"We've spent a lot of time providing options to ensure we have a solid 9-5 (congressional) delegation in 2012 and beyond," Republican consultant Robert LaBrant said in one email.

A Republican congressional aide, Jack Daly, crowed that the process "in a glorious way ... makes it easier to cram ALL of the Dem garbage in Wayne, Washtenaw, Oakland and Macomb counties into only four districts."

Thursday's ruling came in a lawsuit filed by both the league and Democratic voters who claimed districts were shaped by Republican operatives to guarantee the party's dominance in the state Capitol.

GOP lawmakers who intervened in the suit have said the entire proceeding should be halted until the U.S. Supreme Court rules on redistricting cases from North Carolina and Maryland.

The ruling directly impacts the following districts:

For Congress: the 1st, 4th, 5th, 7th, 8th, 9th, 10th, 11th, and 12th.

For state Senate: the 8th, 10th, 11th, 12th, 14th, 18th, 22nd, 27th, 32nd, and 36th.

For state House: the 24th, 32nd, 51st, 52nd, 55th, 60th, 62nd, 63rd, 75th, 76th, 83rd, 91st, 92nd, 94th, and 95th.

Contact Paul Egan: 517-372-8660 or pegan@freepress.com. Follow him on Twitter @paulegan4. The Associated Press contributed to this report.