California’s 2011 Redistricting: Challenges and Controversy

• California’s new voting districts have drawn criticism.
  California voters recently gave authority for the decennial drawing of new U.S. House, Assembly, State Senate, and Board of Equalization districts to an independent citizens commission. The commission’s new maps, released in August, were greeted with concern—including assertions of inadequate minority representation, accusations of covert partisan mapmaking to favor Democrats, and complaints that the maps fail to respect certain geographic criteria the commission was required to consider. Opponents have submitted signatures to the secretary of state for a referendum against the new State Senate maps.
• The commission’s maps modestly improve the potential for minority representation …
  The commission was obligated to comply with the federal Voting Rights Act, which requires the drawing of majority-minority districts under certain circumstances. California’s new maps include six additional majority-Latino Assembly districts, bringing the total to 14, and the first majority-Asian American district in California history. There is also one additional majority-Latino district in the new congressional map and one in the State Senate plan.
• … and score better than the existing maps on traditional geographic criteria.
  The commission was required to respect certain geographic criteria whenever possible: to draw compact districts with simple shapes; to avoid splitting cities, counties, and communities of interest among multiple districts; and to nest two Assembly districts exactly within each Senate district. The commission’s new maps improve compactness significantly, and improve city splits and nesting modestly. There is no notable change in county splits. Impacts on communities of interest have not been evaluated here, because the concept is too subjective for systematic analysis.
• The new maps have a larger number of competitive districts …
  The new maps have more competitive seats than the old ones. Based on a statistical analysis of races over the last decade, there are several seats with more than a two-in-three chance of a close outcome if no incumbent is running: three seats in the State Senate, six in the Assembly, and four in the U.S. House. (The competitive seats are listed in the first table.) By contrast, although a few seats in the previous plan neared that two-thirds threshold in our simulations, none surpassed it.Because these predictions assume no incumbent legislators, many of these seats may not be competitive in 2012. But each has a good chance of a close outcome at some point in the next 10 years, especially if an incumbent retires or is forced out by term limits.
• … but partisan gains will be minimal in most cases, and difficult to attribute to the new district lines.
  In a hypothetical good Democratic year, Democrats could expect to pick up as many as four seats from Republicans in the new House plan, mostly because the 2001 redistricting (drawn by the legislature itself) was uncompetitive and did not allow Democrats to pick up seats as they gained votes over the last 10 years. The new maps increase the likelihood of a Democratic supermajority in the State Senate—and with it the ability to pass tax increases out of that body without Republican support—but only for the 20 seats being contested in 2012. By 2014, the odds of two-thirds Democratic control will be unchanged—and may even be slightly lower—compared to the 2001 legislature-drawn maps. Thus, district numbers, which determine the seats contested each year—rather than the new district lines themselves—are the primary cause of the likely (but probably temporary) Democratic gains under the plan for the Senate. There is little change in the Assembly.

Sources: 2010 registration numbers, California Statewide Database; incumbency and returns, California Secretary of State; district lines: California Citizens Redistricting Commission.