Updated 11:20 a.m. |  The Supreme Court upheld Arizona’s congressional map Monday, declaring in a 5-4 ruling the use of an independent redistricting commission that drew House district lines in the 2012 cycle did not violate the Constitution.  

If the court had thrown out the state’s map, it could have sent the 2016 elections into chaos in Arizona and it could have had implications for neighboring California’s map, drawn by a similar independent commission.  

The case, Arizona State Legislature v. Arizona Independent Redistricting Commission, centered around a 2000 ballot initiative passed in Arizona that removed the power of redistricting from the state Legislature and placed that role in the hands of an independent commission. The commission is made up of five members — two Democrats, two Republicans and one independent member who serves as chairman.

The process cuts out the legislature, governor and general public from making chances to the maps. The only way to challenge the lines is through a successful judicial challenge.

The Arizona State Legislature argued the process violates the Elections Clause of the Constitution, which states, “The Times, Places and Manner of holding Elections for Senators and Representatives, shall be prescribed in each State by the Legislature thereof.”

But the court sided with the redistricting commission in the case.

“So long as a State has ‘redistricted in the manner provided by the law thereof’ — as Arizona did by utilizing the independent commission procedure in its Constitution — the resulting redistricting plan becomes the presumptively governing map,” Justice Ruth Bader Ginsburg wrote in the majority opinion.

Had the court tossed the maps, the Republican-controlled Legislature in Arizona would have had the power to redraw the state’s nine congressional districts more to their liking to make what were competitive districts more favorable to the GOP. Currently, Democrats hold 4 of the 9 seats.

The decision would have favored Democrats in California, where they hold a near supermajority in the legislature. The GOP holds just 14 of the state’s 53 districts.

In anticipation of the decision, parties in both states had met to discuss potential courses of action, according to multiple operatives in both states from both sides of the aisle.

Uncertainty about district boundaries also left some top-tier recruits hesitant to explore or announce bids for House races.

For example, had the Supreme Court tossed Arizona’s map, Democratic Rep. Kyrsten Sinema’s 9th District would have likely become more favorable to Republicans. Both Democratic and Republican operatives speculated those new district lines could have pushed Sinema into a Senate race against GOP Sen. John McCain.

Still, it’s unclear whether Sinema will still consider a Senate race. Democratic Rep. Ann Kirkpatrick is already running for the Senate seat, leaving vacant her 1st District.

Had the court ruled broadly against independent commissions, it could have affected district maps in Idaho, Montana and Washington, which also use forms of independent commissions to draw districts.