I find this almost impossible to believe, but since it was Vegas, maybe. Outside of this place and on my bike, I have a heap of experience in the great outdoors. I also lived in Arizona, and Nevada, where coyotes are frequently seen. They absolutely do not attack humans. If you see one in the wild and walk towards it, it will run off, usually with its tail between its legs. Coyotes are survivors, resilient, and want nothing to do with people, and just do their own thing. The Native Americans revere them for this reason. If the report later comes out that a person was trying to feed it, grab it, corner it (which would be incredibly stupid) and/or they were totally drunk and thought it was a loose pet dog they could catch, that would be about the only way. Now that I think about it, this last scenario is actually somewhat plausible, Vegas and all. A few bites have happened in the outskirts of Los Angeles and Phoenix, almost always tied to human foolishness, but are still super rare.