Retired NYPD Chief of Department John Chell said Tuesday he is "not convinced that the FBI and Pima County sheriff are on the same page" in the investigation into the disappearance of Nancy Guthrie, raising concerns about coordination and public messaging in the high-profile case.

Appearing on Newsmax's "Bianca Across the Nation," Chell said he "always hated the speculation from day one, accusing the family of being involved in this as they go through a horrible event in their lives," after the Pima County sheriff publicly cleared Guthrie's family and called such suggestions "cruel."

But Chell questioned whether that announcement was coordinated with federal authorities.

"I hope that was a coordinated response and planned out by both agencies. I'm not so sure if it is," he said. "I don't even know why you would bring this up. Just leave it alone."

While the sheriff has denied any rift with the FBI, Chell said, "in my opinion, they're not" aligned.

"The hard work is getting done by the investigators on the ground, as we call the boots on the ground. I'm not so sure the higher-ups are on the same page," Chell said.

"Are they in the same room? Are they meeting three times a day? Are they on messaging? I'm not there in Tucson, but just from the outside looking in, I'm not so sure about that."

Chell also criticized officials for publicly discussing DNA evidence, warning it could compromise the case.

"I don't know why they're talking about DNA," he said. "You know who else is listening? The bad person."

He explained that even if investigators receive a hit through CODIS, law enforcement should remain quiet to avoid tipping off a suspect.

"If that is a positive result, the FBI should not put this out whatsoever, because now they're going to cultivate the person of interest and make an arrest. You can't raise up the bad guy," Chell said. "You never talk about DNA in a case like this."

Chell also pushed back on public speculation about potential motives after the sheriff suggested the case might not involve a kidnapping or botched robbery and could be revenge-related.

"We don't know what the motive is. We can speculate all day long," Chell said. "There's a time and place for everything and now is not the time, because what it does, it just brings extra noise into the conversation that we don't need to be having."

Instead, Chell argued officials should focus their public comments on actionable details.

"We want to talk about tips. We want to talk about the bag, the masks, the gloves, the DNA. That's what we want to be talking about. Not this other stuff," he said.

Chell added he would have preferred a more unified public approach from the outset.

"I would have liked to have seen a unified command," he said. "If they're going to do a press conference every day or two, the FBI with the sheriff, be on message. Don't say too much. Don't say too little. There's a fine spot there. I don't think they're there."

He noted that the FBI has largely remained silent since the early press conferences, adding, "That's the way you got to be."

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