Three Arizona utility regulators could be disqualified from setting rates on rooftoop solar due to allegations of bias. 

On Thursday, two former state regulators and a solar company filed motions against Arizona Corporation Commissioners Doug Little and Tom Forese, claiming that dark money spending on their campaigns has tainted the integrity of the commission and how it decides the fees for homeowners with distibuted generation solar panels. It’s widely believed that Arizona Public Service and its parent company, Pinnacle West, funneled around $3 million into Little's and Forese’s campaigns last year. 

After the election, APS moved to reopen the net metering case and raise fees for customers.

"You can't have the utilities that are regulated by the commission spending this amount of money to get commissioners elected," said former corporation commissioner Bill Mundell, a Republican. He, former commissioner and Democrat Renz Jennings, and SunRun have filed the motions against Little and Forese.

"People have a right to expect that in the rate-making process," Jennings said. "That the rate makers are fair-minded and unbiased.”

The motions cites a 2009 United States Supreme Court ruling that found an elected judge in West Virginia had to be pulled off a case involving a coal company that was linked to his campaign contributions.

Hugh Hallman, former Tempe Mayor and the attorney filing the motion, said that case applies to this situation because the commission has a "quasi-judicial role" and subject to similar restrictions as judges.

While there is no definitive proof that Forese and Little benefited from APS campaign contributions, Hallman argues the West Virginia case determined that the "objective" perception of bias was enough to merit the judge's recusal. 

"You have a significant eclipsing of the spending by the candidates themselves, you have a significant impact on the election, and you have a temporal connection," said Hallman in reference to the dark money spending and the effort by APS to raise rates after the election. 

In a separate motion, solar company SunRun also called for Commissioner Bob Stump to be removed from the APS net metering case because of comments he has made criticizing rooftop solar.

According to the motion, Stump has "publicly and extra-judicially stated net metering is a subsidy and imposes an unfair cost shift."

It points to a story authored by Stump and presented at a utility trade organization conference, in which his character George, "installs utility owned rooftop solar to make his life easier thereby living up to what Goldwater called 'true conservative principles' by not embracing a net energy metering subsidy George thinks is unfair."

Requests for comment on Thursday afternoon from Stump, Little and Forese were not returned.

In recent weeks, the two other corporation commissioners, Bob Burns and Susan Bitter Smith, have pushed for public services companies to voluntarily refrain from financially backing candidates for the commission. This effort has received pushback from Forese, Little and Stump, in part because such a move would limit the free speech as defined in the Supreme Court's Citizen's United decision.

Burns has also said he intends to exercise the commission's power to subpoena records that could shed light on whether APS has put money into the elections. Recently, former Arizona Supreme Court Justice Thomas Zlacket filed an opinion arguing the commission does have the authority to request information from the utilities on their campaign spending on commission races. 

The commission has 20 days to make a decision on the motions. If the commissioners do not recuse themselves, Hallman said there are several legal routes, including appealing to the Superior Court. 

This is only the latest controversy surrounding the commission. Earlier this month, a local attorney filed a complaint with the Arizona Attorney General's office seeking the removal of Bitter Smith because of her supposed ties to the telecommunications industry, which she regulates.