By David G. Savage, Tribune Washington Bureau (TNS)

WASHINGTON — The Supreme Court on Monday upheld the kind of independent redistricting commissions used in Arizona and California to prevent partisan gerrymandering.

The 5-4 decision bolsters an increasingly popular political reform adopted by voters in California and other states to transfer authority to draw districts from state legislators to a nonpartisan citizen panel.

Ruth Bader Ginsburg said the Constitution gives states broad leeway to decide on their election rules, and states like Arizona and California may rely on “direct democracy” that allows the voters to decide.

“The people of Arizona turned to the initiative to curb the practice of gerrymandering,” she said, and nothing in the Constitution forbids them from making that decision.

The four most conservatives justices dissented.

In dissent, Chief Justice John Roberts accused the majority of performing a “magic trick” by interpreting the Constitution to allow the people, not the legislature, to set the rules for electing members of Congress.

He agreed with Arizona’s Republican legislature that it should have the exclusive power to decide on districts for members of Congress. Justices Antonin Scalia, Clarence Thomas and Samuel Alito agreed.

The decision turned on a somewhat obscure provision in the Constitution. It says: “The Times, Places and Manners of holding Elections for Senators and Representatives, shall be prescribed in each state by the Legislature thereof, but the Congress may at any time by Law make or alter such regulations.”

Arizona’s voters passed a state constitutional amendment in 2000 to remove the redistricting authority from the state legislature and to turn it over to a new Arizona Independent Redistricting Commission.

Three years ago, Arizona’s Republican lawmakers sued in federal court seeking to overturn the decision of the voters. They said the Constitution reserved this power to “the Legislature thereof,” and this authority may not be taken away.

Defenders of the commission argued the state’s law-making authority can rest with the people when they pass propositions.

The case of Arizona State Legislature vs. Arizona Independent Redistricting Commission called on the high court to resolve a dispute between two parts of the same state’s governing structure.

If the court had struck down the independent commissions, it would have threatened numerous congressional districts in Arizona and California that were drawn by nonpartisan citizen commissions.

In addition, five other states have semi-independent commissions that could have been affected by the ruling: Washington, Idaho, Montana, Hawaii, and New Jersey.

The decision is a victory for reformers who saw independent commissions as the best weapon to stop politicians from manipulating electoral district lines to protect incumbents or political fiefdoms. Three former California governors — Pete Wilson, George Deukmejian, and Arnold Schwarzenegger — filed a friend-of-the court brief urging the justices to uphold the state’s independent panel.

With 53 members, the California delegation in the House of Representatives, 38 Democrats and 15 Republicans, is the largest in Congress.

In 2008, Californians approved a ballot measure to shift the redistricting power for state Legislature seats to a citizens commission. Two years later, voters approved a second measure to extend its authority to congressional districts.

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Photo: North Charleston via Flickr