On March 25, Monday, a 3-judge U.S. District Court will hold a trial in Harris v Arizona Independent Redistricting Commission, 2:12cv894. The issue is whether the state’s U.S. House districts are equal enough in population to be constitutional. See this story.
Another case pending against the Arizona U.S. House districts is moving much more slowly. That case, Arizona State Legislature v Arizona Independent Redistricting Commission, 2:12cv1211, concerns whether having an independent redistricting commission draw U.S. House districts is unconstitutional. The legislature argues that the U.S. Constitution, Article One, provides that only legislatures, and not independent redistricting commissions, can draw U.S. House districts. That case is still bogged down over the issue of whether 3 judges are needed, or just a single judge.