In 2000, Arizona voters amended the state’s constitution to give authority over redistricting to a five-member independent commission. Taking that authority away from the state legislature was supposed to take the politics out of redistricting – a key factor in a case before the Supreme Court last Term, in which the Justices rejected a challenge to the commission’s power to draw federal congressional districts. But a lawsuit now before the Court brought by a group of Arizona voters alleges that the commission, while supposedly non-partisan, is actually anything but. During the redistricting that followed the 2010 census, Wesley Harris and his fellow challengers contend, the commission deliberately put too many voters in sixteen Republican districts while putting too few in eleven Democratic districts. This means, Harris argues, that the votes of residents in the overpopulated districts effectively count less than the votes of their counterparts in the underpopulated districts – a violation of the constitutional principle of “one person, one vote.” The Supreme Court will hear oral arguments in Harris’s challenge on Tuesday, in a case that – depending on how broadly the Justices rule – could affect legislative maps far beyond Arizona.
Arizona’s constitution requires legislative districts to be redrawn every ten years. It also directs the commission to consider several specific criteria when drawing redistricting maps for the state legislature: the federal Constitution and the Voting Rights Act; creating districts with equal populations; creating districts that are geographically compact and contiguous; preserving groups of people with common bonds or interests, which are often racial or ethnic; adhering to geographic features such as municipal or city boundaries; and maintaining political competitiveness, as long as it will not undermine the other criteria.
The first issue before the Court on Tuesday arises from Harris’s accusation that the commission over-populated some of the districts that it drew in the post-2010 legislative maps to favor the Democratic Party. Harris (who has the support of Michele Reagan, Arizona’s chief elections official) is adamant that he and his fellow voters are not challenging the role of party politics in redistricting, standing alone: he colorfully tells the Justices that “partisanship in redistricting is like gambling in a casino. Of course partisanship is present” in redistricting. Nor, Harris emphasizes, is he arguing that the commission was required to achieve “precise mathematical equality” in drawing the state legislative maps. But what the commission cannot do, he maintains, is draw legislative maps that apportion the state’s population unequally because it wants to favor one political party.