Nancy Guthrie case: Former lieutenant reveals major challenges investigators face in finding 84-year-old, ‘The evidence is…’

The terrain that runs through the city and the rest of Pima County is typical of the area.

“The entire Tucson Valley is really built around these arroyos and these ephemeral rivers,” Smith said. “It’s really the greenbelt here, except we don’t have parks and stuff like other places across the country, we have this wonderful desert area. But again, it works between the houses. It’s like a giant alley through the community.”

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Smith explained that while they can make good hiding places, rain can quickly wash away evidence.

“Evidence is provisional,” he said. “Once it rains, your footprints disappear, the sun stings other forms of evidence, and frankly it’s a very difficult place to investigate crime.”

Smith noted that the man captured in surveillance footage from Nancy Nestor’s doorbell camera appeared to be wearing a “Mexican carry” style holstered handgun.

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“My first thought is always Mexico where major crimes occur because it’s a great safe haven and it’s hard for us to follow,” Smith said. “But in this case, it was clear that someone was taken on purpose. I think that’s why we need to wonder, maybe she was taken to Mexico?”

“My personal theory is that if Mexico was suspected, it would become a federal investigation,” Smith added. “There seems to be a lot of effort to get the federal government involved in this case. The best thing to do is deny the possibility of any interstate or international transportation of bodies or kidnapping.”

Smith noted that Nancy’s community is only about 60 miles from the border town of Nogales.

“You cross the border, on the Arizona side, and it’s a small town, a relatively small town,” he said. “Across the border is the main urban area, with a population of 300,000.”

Smith added that this can make it easier for them to integrate.