Caleb Flynn's mistress avoided charges despite murder texts as her attorney reveals why

The attorney for Caleb Flynn's former mistress is pushing back against suspicions that she helped plot the murder of the former "American Idol" contestant's wife, telling Fox News Digital that disturbing messages about wanting Ashley Flynn dead were not evidence that his client took part in the , killing.

Dayton defense attorney Nick Gounaris, who represents Alleigha Botner, said investigators reviewed her messages with Flynn, cellphone records and surveillance footage as they worked to determine whether she had any involvement in the crime.

Botner's secret affair with Flynn became a central part of his trial, where jurors heard exchanges about killing his wife, including a suggestion to hire someone to do it. Flynn was ultimately convicted on Sept. 29 of murdering Ashley and sentenced on Monday to life in prison without the possibility of parole.

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"I think the reason that she wasn't charged is just because you say something, you still have to show that that person was somehow involved," Gounaris told Fox News Digital. "The evidence that was reviewed, the evidence that was developed, the evidence that they secured through all of these different avenues did not suggest anything that involved Alleigha Botner in the death of Ashley Flynn."

Gounaris said he initially worried Botner could become a target of the investigation after she spoke to police without an attorney and was not entirely forthcoming about her relationship with Flynn.

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Investigators had begun uncovering the affair while examining the Feb. 16 shooting at the couple's Tipp City home, where prosecutors said Flynn shot his wife twice in the back of the head before staging a break-in.

Botner eventually acknowledged the relationship, but her family became concerned about her legal exposure and contacted Gounaris, who began speaking with investigators to determine whether she was a witness or potential suspect.

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"As a defense attorney, my first reaction is, wait a minute, we've got to be very careful ... we've got to be concerned that she might be a target here," Gounaris said. "So ... let me bring her into the office. Let's protect her. Let me now be her advocate. Let me speak with investigators and let me then determine, you know, where this is going."

As more evidence emerged, Gounaris said, investigators increasingly treated Botner as a witness, and nothing they uncovered suggested she participated in Ashley's murder.

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Jurors heard that Flynn and Botner exchanged over 107,000 messages during their affair, including conversations in which Flynn repeatedly expressed a desire to kill his wife. I