LANSING, Mich. (AP) — Current and former Black state lawmakers in Detroit announced a pending lawsuit to block Michigan’s newly drawn congressional and legislative districts, contending they illegally dilute the voting strength of African Americans.

The step Monday came days after the new Independent Citizens Redistricting Commission finalized U.S. House and legislative maps to take effect in 2022 and last 10 years. The plans are fairer politically to Democrats but have drawn criticism from Black legislators and the state’s civil rights department because they slash the number of seats where African Americans account for a majority of the voting-age population.

The old maps had 15 such seats by the end of the decade: two in the U.S. House, two in the state Senate and 11 in the state House. Now there are seven, all in the state House.

Commissioners have said Black voters can still elect their candidates of choice without comprising at least half of a district’s electorate.

The suit, though, will allege violations of the U.S. Voting Rights Act and the Michigan Constitution. The No. 1 map-drawing criteria for the panel was to comply with the 1965 law, which bans discriminatory voting practices and procedures.

Nabih Ayad, a lawyer planning to file the complaint in the Michigan Supreme Court, said the new maps — regardless of whether they are good for Democrats or Republicans — disenfranchise African Americans who are left with the “short end of the stick.”

The 13-member commission and its lawyers have said federal law does not require majority-minority districts. Bruce Adelson, who advised the panel on Voting Rights Act compliance, told commissioners there was a lot of “misinformation” or “a lack of information” being circulated by critics of its approach.

“As shared previously, we believe in the advice of our Voting Rights Act legal counsel that we comply with the Voting Rights Act,” commission spokesperson Edwards Woods III said.

The voter-created panel took over the once-a-decade process that had been handled by the Republican-controlled Legislature and resulted in partisan gerrymandering. Commissioners undid “packing” of African American, heavily Democratic voters in Detroit, which has one of the highest percentages of Black residents in the country.

The city had five state Senate districts. It will have eight under the new map, for instance, after new seats were combined with suburban areas in Oakland and Macomb counties.

Many of the minority-opportunity districts drawn in 2011 had far more African American voting-age residents than were needed to elect candidates of choice, according to Lisa Handley, one of the commission’s experts. She submitted a report to the panel saying candidates preferred by Black voters can win general elections if the seats are not 50% African American. But she also noted a lack of data to discern how Black candidates may be affected by white voters in primaries, which decide many races.

“Detroit deserves to have Black leaders,” said ex-state Rep. Sherry Gay-Dagnogo, now a school board member. “We want to make sure that our children have an opportunity to see themselves in the Legislature and for people that will fight for them in our classrooms, in our schools to advocate for policies.”

She urged the Michigan Democratic Party “to stand with us” even if the maps are fairer to the party as a whole.

“This is unacceptable. We can do better than this,” Gay-Dagnogo said.

The lawsuit, if successful, would force the commission to revise the maps.

Lavora Barnes, chair of the Democratic Party, said she does not want to see the diversity of lawmakers diminished.

“The MDP is committed to fighting to ensure fair representation for all Michiganders including giving Black and Brown voters the ability to elect their candidate of choice in a general election and in a primary,” she said in a written statement.