Once there was an offhand comment about Soylent Green, and he said, "I've seen the stuff." It was in a bottle that the murderer kept in his fridge. If the police hadn't thought to do a DNA test on the liquid, they wouldn't have realized what it was.
Every Spring NYC has "floaters". These are people who died and were thrown into the river. Often with weights attached. As the water warms slightly, the body starts decomposing and eventually bloat from the gas makes it buoyant so it comes to the surface.
He once commented, "I don't think that there is a way that one human can kill another that I haven't seen." He then began giving a long list.