SPRINGFIELD — Plaintiffs in two lawsuits challenging the state’s legislative redistricting plan have filed new complaints in federal court charging that the district maps that lawmakers approved in August dilute Latino voting power and thus violate the U.S. Constitution and the Voting Rights Act of 1965.

The Mexican American Legal Defense and Educational fund, or MALDEF, and legislative Republican leaders both argue that while the Latino population in Illinois experienced strong growth over the last 10 years, the new maps actually reduce the number of Latino “opportunity” districts — those in which Latinos make up 50 percent or more of the voting-age population.

“The General Assembly did not merely fail to create more Latino opportunity districts, it created fewer of them,” MALDEF argued in its latest filing.

Both amended complaints were filed in federal court for the Northern District of Illinois on Friday, Oct. 1, one week after Gov. J.B. Pritzker signed the newest maps into law.

Both lawsuits name House Speaker Emanuel “Chris” Welch, D-Hillside, and Senate President Don Harmon, D-Oak Park, as defendants, along with the Illinois State Board of Elections and its individual members, as defendants. Both seek to have the redistricting plan invalidated and new maps drawn.

The two sets of plaintiffs originally filed lawsuits shortly after lawmakers passed the first redistricting plan for the Illinois House and Senate during the regular spring session. Those maps were based on population estimates because the Census Bureau had not yet released official census data.