An Australian woman claims her mother-in-law was killed in their home by unknown assilants, but data from the victim’s Apple Watch contradicts that testimony.

An Apple Watch tracks the wearer’s heartbeat. This means it knows exactly when that heart stops, allowing Adelaide police to know precisely when this murder had taken place. And that was far earlier than claimed.

Future versions of the Apple Watch may be able to identify owners just by taking their pulse.

Apple was awarded a patent this week that details the use of biometrics on a smartwatch that can identify the user based on their heart rate and other variables. All without the users having to make any input.