When former Nashville Mayor Megan Barry admitted to having an affair with her police bodyguard, the TBI went after the couple's phones looking for evidence.
But, facing similar allegations, it appears the former acting director of the TBI may not be getting the same treatment.
"Jason Locke still has his TBI-issued cell phone," said TBI spokesperson Josh Devine.
Having the head of the TBI facing a criminal investigation is an unprecedented situation. Locke is now on administrative leave - and other agencies are handling the investigation.
When Barry faced accusations of having an affair on the taxpayers' dime, DA Glenn Funk brought in the TBI to investigate.
But that's the agency Jason Locke headed and where he might be expected to return, if cleared.
So, NewsChannel 5 has learned, this investigation is being handled by auditors from the state Comptroller's Office and agents of the Criminal Investigation Division of the Highway Patrol.
"Having someone who is not only with the TBI, but was running it at the time these things broke, that's extraordinary," said veteran Nashville lawyer Gary Blackburn.
Blackburn noted that when the TBI was investigating Barry's affair with police Sgt. Rob Forrest, one of the first things they did was to seize Forrest's phone.
They also issued a search warrant for Barry's phone looking for evidence.
In Locke's case, his wife emailed the governor, saying: "He has done away with the state phone that he used during this affair and was issued a new state phone and began using the WhatsApp to continue the affair."
Blackburn said Locke's phone could be a key piece of evidence.
"The district attorney has the authority to authorize seeking of search warrants, for example, from a judge," he added. "That was done in the case of Forrest and Mayor Barry. If that's not done here, then plainly these persons aren't being treated in the same way."
Funk's office refused to comment on why, despite the precedent in the case of the former mayor, it might or might not be pursuing certain evidence.
While much of the attention has been focused on the role of the Comptroller's Office in the investigation, Blackburn said that state auditors have limited powers.
"The Comptroller, Justin Wilson, does an outstanding job with investigations, but he's not a criminal investigative agency," the Nashville attorney said.
"What he will do, his department will do, is to audit and make comparison of numbers and events. That's very valuable, but that's not a criminal investigation."
Earlier this year, NewsChannel 5 Investigates raised questions about the TBI's use of its $10 million plane - and about who investigates the TBI.
In that situation, the Comptroller's Office said, when they had asked to see certain flight logs, the TBI refused, saying any flights related to investigations were off-limits -- even for state auditors.
"We had trouble getting all the information that we would like to have seen from TBI," spokesperson John Dunn said at the time.
I think what we found at TBI was an attitude of 'trust us.' But for us that's not always good enough. We want to be able to verify as well."
There has been some confusion in recent days about the role of the Department of Safety.
And it was only late Wednesday that we got specific details about the involvement of agents from the Criminal Investigation Division of the Highway Patrol.
They have law enforcement authority that state auditors don't have.
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