The Supreme Court announced Monday that it will take up a case involving partisan redistricting in the state of Wisconsin.

• Background, from the Washington Post: "The court accepted a case from Wisconsin, where a divided panel of three federal judges last year ruled last year that the state's Republican leadership in 2011 pushed through a plan so partisan that it violated the Constitution's First Amendment and equal rights protections."
• Why it matters: "[T]he Supreme Court has never found a plan unconstitutional because of partisan gerrymandering. If it does, it would have a revolutionary impact on the reapportionment that comes after the 2020 election..."