PHOENIX - An administrative law judge on Tuesday threw out charges that Attorney General Tom Horne and an aide violated state campaign finance laws, saying the secretary of state did not follow the right procedure in referring the case for investigation.

Judge Tammy Eigenheer did not address the contention by Maricopa County Attorney Bill Montgomery that Horne had illegally coordinated his 2010 election campaign with Kathleen Winn, who led what was billed as an independent expenditure committee. The charge followed an FBI investigation of Horne.

Eigenheer said she dropped the charges because Secretary of State Ken Bennett should never have referred the case to Montgomery in the first place. She pointed out that state law requires those complaints to go to the Attorney General's Office - headed by Horne, and where Winn now works.

Montgomery argued that made no sense, given the "obvious conflict," and Bennett was entitled to seek out someone else to pursue the matter.

Eigenheer, a state hearing officer, disagreed, saying the law is clear. And she said it would be up to Horne's office to disqualify itself from the inquiry, not the option of Bennett or Montgomery.

She also rejected a separate contention by Montgomery that his office has authority of its own to pursue campaign finance violations.

Jerry Cobb, Montgomery's spokesman, said an appeal is planned.

State law allows any group to conduct a campaign for or against a candidate, but these must be independent, with no coordination between the candidate and those running the committee.

The FBI, acting on a tip, concluded that was not the case for Horne's campaign.

Bennett said the federal agency found emails that "unquestionably demonstrate Attorney General Horne actively seeking funds for the independent expenditure committee."

Montgomery added there were "contemporaneous emails and telephone conversations on how much money was expected from this particular source of funds."

There was also information shared about what polling had shown needed to be the message of the independent campaign's television ad being purchased by Winn's committee. And Montgomery said there were communications "about why some of the messaging needed to be changed."

Horne said investigators "misread" the emails.

For example, he said there is a notation on an email Winn was sending to her consultant about what she wanted in the TV ad. And Horne said there's also a notation Winn made when, at the same time, she was on the phone with Horne.

"We checked the records and she was on the phone with me about something else," he said.