The search for Nancy Guthrie, the 84-year-old mother of Today anchor Savannah Guthrie, is now being slammed by a private investigator who says the case could end up as a cautionary tale for police academies.

Nancy was last seen on January 31 and reported missing on February 1, after she vanished from her Arizona home. According to reports, her phone, keys, and wallet were left behind — but she was gone.

Investigators reportedly found signs that sent the situation into full panic mode: indications of forced entry and blood on the door, porch, and driveway. Authorities later released images and video of a masked man, believed to be armed, seen on Nancy’s doorbell camera footage.

Now, a polygraph expert and private investigator is claiming major mistakes were made early on.

“This investigation is going to be written into the textbooks… of how and what not to do,” Lisa Ribacoff-Mooney, owner of Interpoint Investigative Services, alleged in an interview.

Her biggest issue? The crime scene.

Ribacoff-Mooney claimed law enforcement didn’t keep the home secured long enough — and that repeatedly closing it off, reopening it, and then shutting it down again was a worst-case scenario.

She alleged that the back-and-forth could have led to contamination, with extra DNA and fibers potentially brought into the home after it was secured a second time.

If a suspect is ever arrested and the case goes to trial, she warned that defense attorneys could use that against prosecutors — arguing evidence wasn’t handled properly.

Her suggested fix was simple: keep the home locked down longer and complete thorough forensic sweeps before allowing anyone back inside.

She also criticized the handling of key video evidence. Ribacoff-Mooney claimed it took days to obtain and release the Nest camera footage — and argued that doorbell video should be treated as urgent because device settings and overwriting can become an issue.

And then there were the public updates.

Ribacoff-Mooney accused Pima County Sheriff Chris Nanos of doing too many press conferences without meaningful new information, claiming the repeated appearances could spook the public, tip off potential suspects, and even influence witnesses.

Nearly six weeks later, Nancy remains missing — and authorities have not identified a suspect.