(CN) - Arizona voters accusing a redistricting commission of favoring Democrats struggled in a Supreme Court hearing to overcome the outcome favoring Republicans.
"It's off that you're making this charge, that there was an impermissible effort to increase the Democratic authority, power, in the Legislature, but the end result was that the Arizona plan gave Republicans more than their proportionate share of seats in the state legislature," Justice Ruth Bader Ginsburg said, according to a transcript of the Tuesday hearing.
"Well, we would say, Your Honor, that a - an incompetent gerrymander is no less a gerrymander when it unequally apportions the population than a competent gerrymander that obtained the partisan objective," Arent Fox attorney Mark Hearne responded.
Hearne, whose firm is based in St. Louis, Mo., represents Wesley Harris and 12 other Republican voters who filed suit against the Arizona Independent Redistricting Commission.
Proposition 106 created the commission in 2000 to end gerrymandering that comes along with legislative attempts at drawing congressional district lines. In Arizona, the task falls to a five-member commission envisioned as independent.
No holders of public office may sit on the commission, nor can candidates, and no more than two members of the five-person commission can represent the same political party. The fifth member, who serves as chair, may not be registered with any party already on the commission.
Arguing in support of the Republican voters, Arizona Attorney General Mark Brnovich argued that good intentions in drawing the districts do not matter when the commission undermines the principle of "one person, one vote."
"Essentially what happened was by overpopulating the other districts, the voters in the overpopulated districts had their votes diluted," Brnovich explained. "And by diluting those votes, it violated the Constitution."
Hearne told the justices that the commission adopted boundaries with populations that deviated by 8.8 percent for two reasons.
"The first reason was to obtain a partisan advantage for the Democrat party," Hearne argued. "The second reason was a perceived belief that malapportioned districts were necessary to obtain Justice Department preclearance approval."
Justice Samuel Alito posed that there might be a situation in which the only way to respect city or county lines would be to underpopulate some districts.
"Justice Alito, the irony is in the draft maps," Brnovich said. "Seven of the 10 minority-ability-to-elect districts were underpopulated. However, when the Independent Redistricting Commission went from the draft maps to the final maps, there was a one-way ratchet. They intentionally and systemically underpopulated those districts."
Brnovich later admitted a slight deviation would be permissible, but only if it was incidental and not intentional.
Justices Elena Kagen and Antonin Scalia grilled Brnovich on that reasoning.
"The road to hell is paved with good intentions," Brnovich said. "And so our position is, regardless of their intention, if they are doing it in a systematic way or intending to overpopulate certain districts, underpopulate other districts, that is unconstitutional."
Scalia also questioned Paul Smith, an attorney for the commission, about his client's intent.
"There may have been two of the five commissioners who, as to one district, District 8, had some mixed motives in urging that the district be made more competitive," admitted Smith, an attorney with the firm Jenner & Block in Washington.
Smith denied, however, that the commission acted with partisan motives.
"The decision to move population around and make that district somewhat more competitive, even if it was motivated by partisanship, has nothing to do with what we're talking about here, which is the 8.8 deviation," he argued.
And, despite any motive, that district in question remained "largely Republican-leaning," Smith said.
Alito interrupted to call that "a red herring."
"We don't need to discuss the issue of parity," Alito said. "If you have a system of proportional representation and you get 55 percent of the vote, you'll get 55 percent of the representatives."
Smith said that, if partisanship is going to be found to be illegitimate, it should at least be the predominate issue in the case.
Kennedy asked if Smith was "saying that it is all right to use an illegal standard, in part, to reduce equal representation."
"For all the same reasons that the court has many times said we're not going to say any racial consciousness is enough to invalidate it unless it predominates, I would think you would want to follow the same approach, even if you're going to adopt the parity between racial considerations and partisan considerations, which makes no sense," Smith explained.
Harris and his fellow challengers had appealed because the three-judge panel assigned to their case found that the population deviations were primarily a result of good-faith efforts to comply with the Voting Rights Act.
The case was one of three redistricting issues that the Supreme Court addressed Tuesday. Earlier in the day, the court had ruled on a Maryland case in which a federal judge violated procedure by disposing of a gerrymandering challenge himself, rather than by convening a three-judge panel.
Also on the calendar Tuesday was hearing on redistricting in Texas.
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