responsibility

The people that passed by that guy should have stopped to help, but it doesn't mean they are responsible for his death. However, they might have been able to stop it, so that does make them pretty stupid. The person that was at fault was definately the stabber though.

I think if you aren't aware of your actions then you shouldn't be held responsible, but it depends on the circumstance. If you are drunk and you do something to harm someone else, then you should be held responsible because if you are that stupid as a drunk it is your fault for drinking in the first place. However, if it is something else, like a mental problem, then it isn't there fault if they don't really know what they are doing.