I’ve been fascinated by the following quote & initially assumed it was a case of bad wording. Then I saw it in multiple articles from different media sources, yet some said the same thing with slightly different wording. Perhaps it was a case of poor/inaccurate reporting, but after further thought, perhaps it isn’t.
Here is the quote : ‘Mr Fisher said the investigation of communications data concluded "the deceased and her mobile telephone were in the car the accused was driving".’
It can be found here :
Karen Ristevski's accused killer husband made up facts to cover tracks, court hears
The part I found fascinating is that investigation of the communications data concluded that ‘
the deceased and her mobile’ were in the car the accused was driving.
How can the data conclude that Karen was with her phone?
After much thought as to what particular phone sensors might be able to distinguish that, and also send their data out of the handset, I came up with nothing.
Then I realised that some devices people carry do interface with their phone & the data is sometimes broadcast out of the phone as part of the device’s app - specifically fitness devices like the Fitbit.
These devices use sensors to detect steps taken(by vibration), stairs climbed(with an altimeter), and more (sometimes even including the user’s pulse) and the device sends this data by Bluetooth to the user’s mobile phone. An app on the mobile phone then sends this data to a server which interfaces with a fitness website etc.
The broadcast of this data to server can be disabled, but it is enabled by default & disabling it results in some loss of device functionality.
If Karen was wearing such a device, it would send data to her her mobile phone, which would in turn regularly transmit some data to a server.
If Karen’s mobile phone is taken for a drive, but Karen (&and the device) don’t come along for the ride, her phone no longer receives a Bluetooth signal from the device & it stops sending data to the server.
If Karen’s mobile phone is taken for a drive, and her phone continues to send data from the device to the server, then Karen’s phone is within Bluetooth range (close proximity) of the device for the duration of that drive.
In the latter situation, given Borce’s phone was tracked along the same path with Karen’s phone(until he turned it off), we either believe that Borce drove with her body(still wearing Fitbit or similar) and phone in the car, or else we believe that after Karen went for a walk to clear her head, Borce drove Karen’s car & for some odd reason took both her phone & her Fitbit along for the ride...
For information about what these devices do & their phone apps then broadcast, check out
How it works: We explain how your fitness tracker measures your daily steps or for further details, Google for ‘what data do fitness apps send’ sans quotes.
There have been murder convictions secured in the past where key parts of the evidence came from these devices.
