So I'm hoping I might harness the distributed genius of Teh Internets for a long-term project I'm working on. I'm looking for stories that fit the following description: A big group—maybe a whole society, maybe an organization within it, like a corporation or government agency—is involved in doing something that's not just morally wrong, but ought to be pretty obviously so to anyone with a normally developed moral sense. And in fact, many of the participants probably do realize it's wrong. But either from fear of reprisal, or respect for authority, or conformist instinct, the large majority go along. But a minority (maybe a minority of one) do not.
Concrete examples of what I'm thinking of might include: Holocaust rescuers; the people in the Milgram experiment who refused to keep shocking the "subject"; whistleblowers in corporations and government; Natalia Dmytruk, the Ukranian sign-language translator who warned viewers they were being fed propaganda; UN General Romeo Dallaire, who disobeyed an order to withdraw from Rwanda that would have left tens of thousands of Tutsis at the mercy of Hutu genocidaires.
Examples where the relevant parties are still alive (and therefore available for interview) are preferable, but historical ones are good too. Drop suggestions in the comments—and thanks in advance.