Estimating Time of Death Using a Smartwatch: A Case Report

A deceased individual’s time of death is crucial for solving crimes, but its accurate estimation remains limited. This is a major research topic in forensic medicine, and various methods have been attempted. Recently, cases in which pulse recordings from smartwatches were used to determine the time of death and aid in case resolution have been reported. Photoplethysmography, a technology that measures pulse, is applied to most smartwatches and its accuracy is clinically recognized. However, further research is needed before it can be applied to forensic medicine to estimate the time of death. Here, we report the autopsy case of a 50-year-old man who died in his sleep and whose time of death was estimated based on cardiac arrest detected on a smartwatch., along with a literature review.