Fitbit data used to charge 90-year-old man with murder of stepdaughter

A dead woman’s Fitbit helped California authorities charge a 90-year-old man with the murder of his stepdaughter.

San Jose police charged Tony Aiello with the death of Karen Navarra, 67, after using a combination of data from the victim’s exercise watch and security camera footage.

According to police, officers responded to a welfare check on Sept. 13 and found Navarra “with visible injuries and non-responsive.”

READ MORE: Slain woman’s Fitbit continued logging steps after husband told police she died

Citing court documents, the San Francisco Chronicle reported the woman was found slumped in a chair, holding a large kitchen knife and had a “gaping” slit through her neck. Detectives said the scene appeared to have been staged to look like a suicide.

However, the newspaper reported an autopsy shows Navarra had “multiple deep and intrusive wounds” to her head and face, suggesting the cuts were from a small axe or hatchet.

Investigators had noticed the victim was wearing a Fitbit on her wrist when her body was found and consulted with the company to see if any of the stored data could help with the investigation.

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According to the Chronicle, an employee told police the victim’s heart rate spiked at 3:20 p.m. on Sept. 8 and then rapidly slowed. The device stopped registering a heartbeat at 3:28 p.m.

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During an initial interview, Aiello told investigators he had stopped by his stepdaughter’s home during the day on Sept. 8, and claimed to have seen her driving by his home a few hours later.

However, nearby cameras captured Aiello’s car at Navarra’s home on Sept. 8 at the same time her Fitbit showed her heartbeat rapidly falling.

Aiello denied killing the woman, despite police finding bloody clothes in his home. He was arrested on Sept. 25 and booked into a jail on a charge of murder.

This isn’t the first time Fitbit data led to murder charges.

A 40-year-old Connecticut man was charged with killing his wife in 2015. The man initially told police a masked man had entered their home, shot his wife and tied him up before he burned the intruder with a torch. However, police wrote in an arrest warrant that the victim’s Fitbit was logging steps after the time her husband told authorities she was killed.

—with a file from the Associated Press