Nancy Guthrie mystery could be solved with 'crowdsourcing' help, private eye says

Over more than 21 weeks since the suspected abduction of Nancy Guthrie, the FBI and Google made a groundbreaking recovery of Nest doorbell video, two men have been detained and released without charges, thousands of tips have been investigated — and yet her whereabouts remain unknown.

Herman Weisberg, a former NYPD detective turned high-profile private investigator, believes one phone call could still crack the case.

"You've got to have a lot of patience when you're dealing with that because you might just be on your 7,000th call and your 15th cup of coffee that day, but the 7,001st call could be the one that's really got a piece of valuable information in this," the managing director at the New York-based private firm SAGE Intelligence told Fox News Digital. "The 7,001st call could be the one."

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With the investigation grinding on for more than 150 days and a steep decline in updates from authorities, Weisberg said the sheer volume of public interest in the case could ultimately become one of investigators' greatest assets.

"The awareness that comes with a high-profile crime like this should be an advantage in solving it," he told Fox News Digital.

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Weisberg points to cases like that of Gabby Petito, where ordinary citizens reviewing their own dashcam footage provided the breakthrough investigators needed to find her remains in a remote Wyoming campground.

Other cases solved with help from the public include the Boston Marathon bombing, where tipsters reported the movements of the Tsarnaev brothers after the deadly attack, and the abduction of Elizabeth Smart, who was abducted as a teenager and rescued after attentive Utah residents recognized her suspected kidnappers from news coverage of the case and called police.

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"Crowdsourcing wins cases these days, you know, all the armchair sleuths and the true crime fans that are out there," Weisberg said. "Maybe one of them is like what I always say, is the one that looks outside their window and said, 'That's strange, that car's been parked out there too long. It's got Arizona plates.' You know, it's a stolen car. Get the police to come."

While he said he's surprised that digital forensics haven't solved the case already, not everything goes investigators' way.

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"Actually, I'm pretty shocked that this case didn't come down to technology," he said. "A perfect example is that Kohberger case in Idaho. Technology was the case breaker for them, but anything can happen in a case like this. I think the old expression, three can keep a secret if two are dead. If this was a solo perpetrator of this crime, we lose a big advantage of somebody else being able to point the finger here. Whatever it is, my personal idea on this is it was a crime that went very wrong from the beginning. We didn't have some of the advantages, some of investigative opportunities there because this didn't play out the way that the perpetrator intended it to."

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On the other hand, Weisberg said, as in the Kohberger case, there's a strong chance that investigators are farther along than the public is aware.

"They could be working on a lead right now," he said. And if that doesn't work out, investigators and the Guthrie family are still asking for tips from the public.

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There are combined rewards of more than $1.2 million for information in the Guthrie case, including $1 million from the family for information that leads to her recovery.

Her daughter, "Today" co-host Savannah Guthrie, is asking anyone with information on Guthrie's case to dial 1-800-CALL-FBI.

Tips can be provided anonymously to Tucson's Crime Stoppers affiliate, 88-Crime, at 1-520-882-7463.

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