Nancy Guthrie disappearance: Sheriff says no arrests, none remain in custody after major operation
Little-known cellphone unit could help crack Guthrie case as digital net tightens: retired FBI agent
The FBI’s Cellular Analysis Survey Team (CAST) is one of the bureau’s most critical tools in missing person cases and may be the key to cracking the Nancy Guthrie case, but retired FBI supervisory special agent Jason Pack said most Americans have never heard of it.
Pack — who served as Chief of Staff for FBI Public Affairs, negotiator and child abduction team leader — told Fox News Digital that authorities likely have suspects in Guthrie’s disappearance, but data is still being refined by the specialized team.
“They have data, mountains of it,” Pack said. “Names have surfaced and been evaluated. Some have been cleared. Others may still be in play in ways we aren’t seeing publicly.”
CAST specialists are trained to analyze cellular data at an extraordinarily granular level.
Pack said the team is not just pulling call logs, but mapping the movement of every phone that pinged off towers in and around the area of interest during the relevant time windows.
“Every cellphone is essentially a tracking device its owner carries voluntarily,” he said. “CAST can reconstruct where a phone traveled, when it arrived, how long it stayed, and where it went next. In a kidnapping investigation, that capability is devastating to anyone who thinks they moved undetected.”
However, Pack said to access phone records and data, agents first need warrants and subpoenas.
“It comes trickling in, sometimes in waves, sometimes in fragments,” he said. “Each new batch of records has to be ingested, analyzed, and cross-referenced against the existing evidence map. Every new data point can confirm a theory, eliminate a lead, or open an entirely new investigative thread. … The search warrants tell us the investigation is active and aggressive. The subpoenas tell us the digital net is widening.”
In the Guthrie case, Pack speculated the court orders are at various stages, and developments are “happening around the clock.”
“What agents and deputies are doing right now is exactly what they should be doing. Letting the cell records, the video, and the tips converge,” he said. “… That’s when you see law enforcement activity like we are seeing or hopefully an arrest. Not before. The investigation isn’t stalled. It’s building.”
Fox News Digital’s Jon Street contributed to this report.
