Our smartwatches and fitness trackers these days come with built-in heart rate sensors. While these might be useful for tracking our workouts and maybe even saving our lives, they can also be used to solve crime. This is how police figured out that an alleged victim of an anti-semitic stabbing might have been lying about the attack.
The victim (now suspect) Sean Sammit had initially claimed that he was attacked when he left a synagogue in West Bloomfield. He said that a man had come up to him and shouted anti-Semitic comments before stabbing him. Sammit said that he had fought off the attacker before driving himself to the hospital.
However, upon further investigation, police found no evidence of such an attack in the parking lot that Sammit claimed the attack took place. They also looked through his Apple Watch and found that his heart rate at the time of the alleged attack was normal, when in reality it should have been higher.