No trance-like state observed in crowd members. I Weakening the power of authority Authority has less power over large numbers. Visibility of authority must be low. Relationship to authority must be low. In many cases, people have reasons to feel angry.
People generally have transgressive impulses.
The crowd must be able to communicate. In the absence of old norms, new ones emerge. Conformity pressures strengthen new norms. The impression of universality. Must be physically possible to transgress.