Last Monday, the Supreme Court announced that it would hear a Wisconsin case that would overturn a highly gerrymandered State Assembly redistricting map that heavily favors Republicans. The Court plans to hear arguments next fall, and it is expected that it will be closely divided. (New York Times, “Justices Take up Gerrymandering Based on Party,” June 20, 2017) Gerrymandering gives those in control of the redistricting process the power to enhance their representation by means of what is known as “packing and cracking”: The ruling party “packs” opponents into a few carefully shaped...