I'm aware there are some artists who have practiced from mugshots. It seemed a little weird (and ghoulish) to practice from a victim. I wouldn't want to make a habit of it. It's too sad! (...and it's a funny by-product to want to do a perfect job....when the person you are drawing is no longer here).
Sketch, Celeste Bergin, Karen Gregory, charcoal on toned paper 6x9 sketchbook