PHOENIX -- Yavapai County prosecutors are defending an FBI agent who testified against Attorney General Tom Horne in a civil campaign finance case from perjury allegations raised by Horne's lawyers.
Horne lawyers say FBI agent Brian Grehoski lied on the stand and want a judge to throw out his testimony.
But prosecutors said in a Friday court filing that at most the FBI agent may have mischaracterized an exchange with a witness on a minor side issue that doesn't warrant throwing out the testimony.
Horne lawyers asked an administrative law judge earlier this week to throw out Grehoski's entire testimony, alleging that he lied on the stand.
Horne and aide Kathleen Winn are accused of illegal communications about a purportedly independent campaign backing Horne's 2010 election campaign.
Grehoski said a real estate agent denied during an FBI interview that Horne consulted Winn on the real estate transaction.
The defense motion asking for his testimony to be barred cites phone records, an audio recording and hearing testimony by Grehoski and the real estate agent, Greg Tatham, as showing Grehoski lied.
Grehoski was the key prosecution witness in the case.
Deputy Yavapai County Attorney Benjamin Kreutzberg wrote in Friday's filing that Tatham, who recorded the call, did say that he knew of no one else who consulted on Horne's real estate deal. He said Grehoski would not lie and there's no evidence he did.
`"As an experienced law enforcement officer, he knew how serious a charge perjury is," Kreutzberg wrote. "It would have made no sense for him to lie about those events."
Horne and Winn say they were talking on the phone about the real estate transaction, not an ad planned by the group headed by Winn to target Horne's election opponent as prosecutors allege.
A state administrative law judge is preparing to rule in the case after a four-day hearing last month. Once issued, the judge's ruling will likely not be the end of the case.
Yavapai County Attorney Sheila Polk can accept or reject the judge's findings and impose sanctions herself. Polk determined in October that Horne violated the law and must repay $400,000 to donors and pay three times that amount in fines.
Horne and Winn could appeal any decision, dragging any final conclusion into the election season, when Horne faces a challenger in August's Republican primary as he seeks a second term.
If he wins the primary, he'll likely face the same Democrat he narrowly defeated in 2010, Felecia Rotellini, a former prosecutor and bank regulator.
Horne and Winn are accused of working together on a campaign ad targeting Rotellini that was paid for by an independent group Winn was running, Business Leaders for Arizona. Such coordination would be illegal in Arizona.