PHOENIX (AP) — Chris Nanos has had a long career in law enforcement, but he admits he isn’t used to the amount of scrutiny that has come with leading the investigation into the disappearance of “Today” show host Savannah Guthrie’s mother. At news conferences since 84-year-old Nancy Guthrie’s apparent abduction from her Tucson-area home, the soft-spoken sheriff of Pima County, Arizona, has tried to walk the line between keeping the public informed while withholding investigation details that