This reminds me of a different experiment where people were taking phone calls (sort of like a customer service or information type thing) when the person they were talking to had a heart attack or stroke. If it was just one person on the call, they would generally go gt help. If there were two or more people taking the call, they would wait to see what the other person would do, leading to deadlock and nothing happening. Unless one of them chose to act, in which case the others would also very quickly act themselves. Your mention of soldiers reminded me of Abu Ghraib, though people usually say that that is more relevant to the Stanford Prison Experiment.This is closer to what you were talking about: people will fill the social role they are expected to take.