Kimberly Robinson for Bloomberg BNA:

The U.S. Supreme Court could radically change how states draw their districts for federal and state elections as Republicans and Democrats are preparing to battle over the next redistricting cycle.

More than 30 years ago, the high court said that considering party affiliation too much in redistricting could cross the line into unconstitutional gerrymandering. But the Supreme Court provided little guidance and federal courts have since struggled to find where that line is.

As a result, states defending allegations that they unconstitutionally relied on race when drawing voting maps often say they were merely relying on politics.

That could end—or at least be seriously curtailed—if the Supreme Court decides to hear Gill v. Whitford.

There, Democratic voters challenging the maps in Wisconsin think they’ve found a way to measure when political consideration in redistricting crosses the line. And a lower court agreed.

Wisconsin Republicans unconstitutionally created maps that disadvantaged Democratic candidates when they drew up new voting maps in 2010, a special three-judge district court panel said in a stunning decision last November. The panel relied on a new standard—the “efficiency gap”—to measure that disadvantage.

That standard attempts to measure the efficiency with which the parties can elect their candidates by calculating the number of votes their voters “wasted.” An efficiency gap in favor of one party suggests that the other was disadvantaged in the voting process.

Now Wisconsin—supported by a dozen other states—is asking the Supreme Court to step in.

The new standard the lower court blessed doesn’t take into account political realities, they argue…..

It’s highly likely the Supreme Court will agree to take up the case due to procedural oddities with redistricting cases, Paul M. Smith, of the Campaign Legal Center, Washington, told Bloomberg BNA. Its “hard to imagine” the justices turning this case away, Smith, who represents the voters challenging the voting maps, said.

This may be one of the last opportunities to convince a majority of justices that the judiciary is capable of policing these claims, Rick Hasen, an election law professor at University of California, Irvine, School of Law, told Bloomberg BNA.

Rumors that Justice Anthony M. Kennedy will retire soon are swirling, and he could provide the critical fifth vote in this area that has often split along ideological lines.

The court will consider whether to hear the case during its June 8 private conference….