In September 2018, Karen Nvarra was found dead in her San Jose home, her throat slit and her hand clutching a kitchen knife. A partially eaten slice of pizza was found on the floor, near her feet.
But the biggest clue the crime scene yielded was affixed to the 67-year-old pharmacy technician's wrist — her Fitbit watch — which would lead detectives to a suspect in her death, her stepfather, 91-year-old Anthony Aiello.
Aiello, who was charged with first-degree murder in the killing, but whose case had not yet gone to trial, died earlier this week due to health complications, his lawyer Edward Caden confirmed with Oxygen.com. His death comes a year and two days after Nvarra was killed. Aiello, who was arrested roughly two weeks after his stepdaughter’s death, according to a San Jose Police Department press release, had pleaded not guilty to the charges.
The elderly man’s last scheduled court appearance was earlier this month, his lawyer said, but he was unable to attend because he was hospitalized due to his “seriously degraded medical condition.” Aiello last appeared in court shortly after his indictment was handed down in August. His legal team hoped the trial would have gotten underway by December.
When police arrived at Nvarra’s home last year, they came across a ghastly scene.
“There were approximately at least 12 wounds to the middle of [Nvarra’s] face and the right side of her head that resulted in open skull fractures — so very deforming injury to her head,” forensic pathologist Dr. Susan Parson testified during pretrial proceedings, according to a court transcript obtained by Oxygen.com.
“She also had two linear wounds on the right side of her neck, and of note, she did not have any injuries to her hand or her arms,” Parson added.
At first, authorities suspected Nvarra’s death might be a suicide, but given the number of stab wounds, medical examiners concluded the death was a homicide.
The San Jose case made headlines across the country because of how heavily law enforcement relied on the fitness tracker’s data to charge Aiello.
Fitbits, popular amongst runners, professional trainers, and every day health nuts, are used to track and synthesize data related to physical activity. The device monitors heart rate, movement, step count, and can mathematically calculate sleep times or when the user’s body is still.
In Aiello’s case, the 91-year-old was connected to Nvarra’s slaying through data that was collected by the woman’s fitness watch, which indicated a sharp rise and then drop in her heart rate roughly the same time prosecutors said the man was at his stepdaughter’s home on the night she died. Aiello said he had seen his stepdaughter earlier that day when he dropped off pizza and cookies for her, and later on, when she drove past his house with an unidentified passenger. But police said footage from a doorbell camera captured Aiello’s vehicle in the driveway at the time of her murder.
“During the window that his vehicle was parked in the driveway, he admitted he was there at her house,” said Brian Meeker, a homicide detective.
“Approximately that same time, her Fitbit ceased to report any type of data. That indicated to me — because the Fitbit was still affixed to her when we found her — that more than likely Mr. Aiello was present when her Fitbit stopped reporting data or her heart stopped.”
Aiello’s defense attorney, Caden, was torn when he learned of his client’s death.
“We’re deeply disappointed with the outcome such as it is,” Caden told Oxygen.com. “The defense of Mr. Aiello was always focused on two things: One, proving that Mr. Aiello was innocent of the charges, and secondly, finding out who the killer actually was.”
Caden, who believes a third person was in Nvarra’s house at the time of her murder, is convinced the real killer has gone undetected.
“We’re really concerned the killer is still out there in the community,” he said. “After Mr. Aiello left the home of his step daughter and went home a couple blocks away, the murder took place, and [the killer] fled after committing that horrendous crime.”
He scoffed at the primary piece of evidence connecting his client to Nvarra’s killing, referring to the Fitbit data as “B.S.” Caden, who explained that Fitbits aren’t “medical grade device[s],” disputed the gadget’s data, citing a handful of peer-reviewed scholarly articles that downplayed the reliability and accuracy of Fitbit.
“A Fitbit exercise tracker is inaccurate 50 percent of the time,” the 67-year-old lawyer claimed.
“As a result, you have an inaccurate device on a victim who had only worn it for about two weeks. The research shows that it is less reliable on a female than a male because of the size of the wrist,” he added.
However, one of the studies Caden pointed to, which found that a particular model of Fitbit inaccurately calculated heart rate readings, reportedly dealt with a different model of Fitbit than the one found on Navarra.
With Aiello’s death, Caden said the case is now closed.
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