The Supreme Court on Monday agreed to hear Wisconsin’s appeal of a lower court ruling that found its 2011 state redistricting plan was unconstitutional due to partisan gerrymandering.

The potential landmark case could decide how far state legislatures can go in drawing up district lines for partisan gain.

The federal district court for the Western District of Wisconsin invalidated Wisconsin's plan for the State Assembly. Similar cases are reportedly pending in North Carolina and Maryland.

ADVERTISEMENT

In 2012, after the map was introduced, Republicans won 60 seats in the 99-seat Assembly, even though the party’s candidates won 48.6 percent of the two-party vote, according to the Brennan Center for Justice.

Federal courts have previously ruled that maps that employ “racial gerrymandering” are unconstitutional. In racial gerrymandering, lines are drawn to lower the influence of minority voters, sometimes by scattering them across different districts.

The challenge to Wisconsin’s legislative lines are different because the challenge revolves around whether district lines can be drawn for a partisan advantage.

“For too long, the important task of redistricting has resembled a back-alley brawl: no rules, no referees, and no holds barred,” Dan Vicuña, Common Cause’s national redistricting manager, said in a statement.

“Technology has made it easier than ever for self-interested legislators to manipulate districts for political advantage, so it is essential that courts step in to protect voters' fundamental constitutional rights.”

Registered Democratic voters in Wisconsin, who challenged the plan, claimed Republicans employed two gerrymandering techniques in drawing the new districts called “cracking” and “packing.” Both diluted the votes of Democrats statewide, the voters say.

Cracking occurs when a party’s supporters are divided among multiple districts so that they fall short of a majority in each one. Packing takes place when one party’s backers are concentrated in a few districts that they win by overwhelming margins.

Correction: A previous version of this story incorrectly said that Wisconsin's Supreme Court had weighed in on the case.