In 1951 social psychologist Solomon Asch performed a famous experiment to test the pressure on individuals to conform to group beliefs. The results explain a lot about the Libor scandal.

In the experiment, groups of college students were shown a card with a line on it. They were then given another card with three lines of varying length and asked which matched the original. The answer was obvious, but a third got it wrong. Why? Because all the other participants, who were plants, gave the wrong answer and the real subjects felt under pressure to agree with the group.