The Yavapai County Attorney's Office will investigate allegations that Arizona Attorney General Tom Horne and one of his aides violated campaign-finance laws during Horne's 2010 election campaign.
Yavapai County Attorney Sheila Polk will handle the case, according to documents obtained by the ABC15 Investigators.
Maricopa County Attorney Bill Montgomery accused Horne and Kathleen Winn of collaborating to quickly raise more than $500,000 to fund negative ads targeting Horne's Democratic opponent during the 2010 election.
By law, candidates are not allowed to coordinate certain activities with independent-expenditure committees.
Horne defeated ex-prosecutor and bank regulator Felicia Rotellini by about 63,000 votes out of a total of 1.6 million ballots cast in the 2010 general election.
Horne and Winn say they did nothing wrong and that authorities have misinterpreted evidence.
Horne's attorney Michael Kimerer told ABC15 that he plans to send Polk an outline of their defense in writing.
Kimerer said he hopes it will convince Polk that the charges are unfounded.