http://www.design.otago.ac.nz/grant/psyc/OBEDIANCE.HTMLhttp://www.garysturt.free-online.co.uk/milgram.htmStanley Milgram, a researcher at Yale conducted an experiment to see how far he could push normal people to administer what amounted to "torture" to test subjects. He had his test subjects ask test questions to a "learner" and then if that learner answered incorrectly or took too long, the test subject was to push a button that would "shock" the learner. (It was all a simulation, but the test subject had no knowledge of this).
The voltage would be raised with each following question, and the learner would increasingly protest the shocks and grow more desperate, but almost 60% of his test subjects followed the experiment till the end - 450 volts of electricity. To a point where the learner would pretty much stop answer (to simulate either death or unconciousness). Its pretty disturbing.
I saw an episode of Candid Camera that had a similar theme. It had 4 guys take a fake job as a security guard at a factory (which is obviously a sweatshop) and they were ordered to pull a switch to electrify a fence if any of the factory workers tried to get out and climb the fence. 3 out of the 4 dupes pulled the switch and shocked the escaping laborers. One of them did it enthusiastically because he really wanted to impress his boss and do a good job.
(Edited to add: ) I'd like to point out that the guy who was most gung-ho and pulled the lever enthusiastically was the youngest of the bunch (20's-30's) and also a minority. The guy who refused to pull the lever and walked off the job was ALSO a minority, so take that for what its worth. The other two guys seemed genuinely conflicted and apologized profusely to the escaping workers, but they pulled the lever and electrocuted them anyway.