Still, the court concluded the Republican challenge failed to present “a workable standard by which to evaluate such claims.”
The court also rejected Republican arguments that the new map sought to dilute the voting strength of a growing Latino population by packing Latinos into an earmuff-shaped congressional district that is currently home to U.S. Rep. Luis Gutierrez of Chicago.
The court said Republicans failed to prove “by a preponderance of the evidence that the state legislature intentionally discriminated against Latinos in passing” the map.
The new congressional map was drawn by Democrats who control the legislature, without any input from Republicans, and was signed into law by Democratic Gov. Pat Quinn. New boundaries are required to be drawn to reflect population changes following the federal census.
But with Democrats in control of the map-making process, the new lines threaten to overturn the 11-8 majority that Republicans gained in the congressional delegation following the 2010 midterm elections. Illinois also loses one House seat in the 2012 elections.
The new map forces several Republican incumbents to run against each other in primaries, face off against a Democratic incumbent or opt to run in new unfamiliar Democratic-leaning districts.
Petition filing for candidates for Congress begins Dec. 23.