Diffusion of responsibility is the tendency for people to feel that responsibility for acting is shared, or diffused, among those present.
Diffusion of Responsibility decrease in individual sense of responsibility for takin action in an emergency because of the presence of other bystanders; the greater the number of bystanders, the less likely each individual is to act.
Diffusion of responsibility refers to social psychology, the suggestion that taking responsibility for initiating action or offering help in an emergency is spread among the people present in the situation. Sometimes the responsibility is so diffuse that no action is taken.