Researchers at Santa Clara University have replicated the findings of the famous Milgram experiment, where by using the trappings of authority they were able to get volunteers to administer torturing electrical shocks to innocent people. (The shocks were simulated, the victims actors.)
If you've never heard of the Milgram experiment, you should stop and read about it right now. Unless you're in a burning building, there is nothing more important you can do - without this understanding of authority, little in the world of human action makes sense.
Is this tendency to blindly follow authority just a laboratory artifact? Sure, there's Abu Ghraib, but maybe that was the result of military conditioning.
Sadly, the case of the fast-food joint strip searches demonstrates that very ordinary people will do horribile things on command of authority, in real life without any special training or conditioning. In over 70 cases spanning a decade, a caller was able to manipulate managers and employees of fast food restaurant into performing strip searches and other abusive acts merely by posing as a cop over the telephone.
And this, my friends, is why we must question authority. Make a habit of it.