Oh, I did a dumb. Capacitive readers use the body's natural electrical signal to form an image of your fingerprint. You can trick them by using something conductive and running the right amount of electricity through.
Dead people don't work though. Not for very long at least.
Your body doesn't all die at once. The parts that need a constant flow of oxygen die within minutes, while some parts take hours. Tissues like skin, tendons and heart valves are viable for harvest for as long as 48 hours after death.
https://australian.museum/about/history/exhibitions/death-the-last-taboo/decomposition-body-changes/
So? Photography is fun. My photos don't exist until I take them.