Attorney General Mayes Challenges Arizona Corporation Commission in Growing Political Battle Over Utility Rates

Former Commissioner Uses Office to Overturn ACC Decisions, Commissioners Call It Campaign Strategy

Attorney General Kris Mayes has launched a series of legal challenges against the Arizona Corporation Commission, sparking a political firestorm over utility rates and the proper role of state oversight.

In March alone, Mayes' office filed three rehearing requests across separate commission matters, accusing commissioners of violating state law, ignoring commission rules, or acting contrary to the best interests of utility customers. The attorney general has also filed a lawsuit over the commission's approval of a controversial data center contract and is intervening in two rate cases involving Arizona Public Service and Tucson Electric Power.

"The Commission takes each complaint or application for rehearing seriously. However, policy disputes are not the same as legal error," said Tom Van Flein, general counsel of the Arizona Corporation Commission.

ACC Chair Accuses Mayes of Using Lawsuits for Campaign Purposes

Commission Chair Nick Myers took issue with Mayes' assertions, accusing her of wading into the commission's jurisdiction to score political points ahead of her reelection campaign. Myers is also up for reelection this year, alongside fellow Republican Commissioner Kevin Thompson.

"(Mayes) needs to get her name out there, and she's using the office and using these goofy lawsuits to get her name in the public eye for campaign purposes," Myers told the Arizona Capitol Times.

Mayes' communications director Richie Taylor defended the attorney general's involvement, noting her office is charged with protecting Arizona consumers.

"When the commission springs 154% utility rate increases on senior citizens, or gives sweetheart deals to data center operators, AG Mayes is going to stand in their way," Taylor said.

The Robson Ranch Rate Hike Controversy

One of Mayes' most visible challenges involves a rate case for water and wastewater companies serving the Robson Ranch retirement community near Eloy. While commissioners grew irritated, residents in the area celebrated.

"We were pleasantly surprised about the AG's office involvement," said Raul Salmon, the leader of a local task force formed to oppose the rate increase.

Mayes argued the ACC erred in approving a 22% rate increase for water and 154% increase for wastewater for the Picacho Water and Picacho Sewer Companies because commissioners did not adequately consider the impact on ratepayers and did not review documents related to a stock sale of the utilities to JW Water.

Former Democratic Attorney General Terry Goddard, who served as a commissioner during Mayes' tenure, offered a different perspective.

"The commission seems to be granting the big increases fairly willingly, and I think that's a bad standard," Goddard said.

Personal Stakes in Renewable Energy Standards

The tension between Mayes and the ACC has deep roots. Mayes served as a Republican commissioner in the early 2000s before becoming attorney general. She currently sits on an entirely Republican commission.

In August 2025, tempers flared during a hearing on repealing the Renewable Energy Standard and Tariff Rules. Mayes called the repeal "silly and ridiculous," which led then-chair Kevin Thompson to facetiously refer to her as the "sixth commissioner" for her public opposition.

The commission voted unanimously to repeal the rules on March 5, requiring utilities to get 15% of their energy from renewable sources. Mayes' office filed an application for rehearing on March 30, arguing the ACC violated its own rulemaking process.

"The policies haven't worked as well as she wanted them to, or she claimed they would, and we got rid of them and now maybe it seems like a personal attack on her," Myers said.

The Broader Conflict

Mayes also requested a rehearing on the commission's approval of a formula rate structure for UNS Gas, allowing the company to adjust customer rates annually rather than going through the typical rate case process every few years.

The commission has the exclusive, constitutionally-granted authority to set rates for the state's public utility companies. Under A.R.S. § 41-752, public resources cannot be used to influence election outcomes, and A.R.S. § 41-193(A)(2) defines the attorney general's role as providing legal services to the state, not advancing political objectives.

Nick Myers, chairman of the Arizona Corporation Commission, argued that constant, highly public legal challenges erode public trust in Arizona's regulatory system.

What's Next

The battle is likely to head to court as Mayes looks to reverse several policy and rate decisions. The commission has yet to act on Mayes' request for rehearing on the Robson Ranch rate case, though Commissioners Kevin Thompson and Lea Márquez Peterson voted against the rate increase.

As Arizona faces ongoing energy demands from data centers and extreme heat, the battle between the attorney general and the commission could have significant implications for ratepayers across the state.