Data collection from fitness tech has crime-solving capabilities

With the surge in popularity of fitness trackers in recent years, the devices' data collections are playing a more present role in the legal system and process, Wired writes.

The intrigue: Fitness devices like FitBit track heart rate, sleep patterns and daily activity. In the 2018 case of California woman, Karen Navarra, her FitBit detailed the last of her heartbeat as she was murdered. Using security footage, officials began to suspect Navarra's stepfather had been to Navarra's home at the time she died, and he was later arrested on murder charges.

• Location data proved useful in a personal injury case in Canada in 2014, as well as a Pennsylvania sexual assault case in 2015, per the New York Times.
• In 2016, FitBit data was used to eliminate a slain Wisconsin woman's live-in boyfriend as a murder suspect, Wired reports.

Between the lines: Using material collected from wearables as evidence comes with the built-in assumption that "data is equivalent to truth," Antigone Peyton, an intellectual property and technology lawyer, told Wired.

• But, but, but ... Wired notes that: "An analysis of 67 studies on Fitbit's movement tracking concluded that the device worked best on able-bodied adults walking at typical speeds. Even then, the devices weren't perfect—they got within 10 percent of the actual number of steps a person took half of the time—and became even less accurate in counting steps when someone was resting their wrist on a walker or stroller, for example."
• What's more: to date, no appellate court has weighed in on a case that cited the fitness tracker data.

The bottom line: "How other judges decide the validity of Fitbit information will likely continue to be decided in the slow burn of the legal system," Wired writes. There remain "many ways the information on these devices can be interpreted."

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